Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.


Search the Community

Showing results for tags 'review'.

More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • Welcome
    • Welcome
  • Beginners
    • Getting Started General Help and Advice
    • Getting Started Equipment Help and Advice
    • Getting Started With Observing
    • Getting Started With Imaging
  • Community
    • Official SGL Announcements and Events
    • StarGaZine
    • SGL Challenges and Competitions
    • SGL Star Parties
    • Star Parties & Astro Events
    • Celestial Events Heads Up
    • The Astro Lounge
  • Retailers
    • Sponsor Announcements and Offers
    • FLO Clearance Offers
    • IKI Observatory
    • Supplier Reviews
  • Astro Classifieds
    • For Sale / Swap
    • Wanted
  • Equipment
  • Observing
  • EEVA (Electronically Enhanced Visual Astronomy)
  • Imaging
  • Science
  • WADAS's WADAS Discussion Forum
  • Beaufort Club's Topics
  • Swindon Stargazers Club's Topics
  • East Midlands Stargazers''s Topics
  • Central Scotland Astro's Topics
  • SGL Cumbrian Skies's Topics
  • Herts, Beds and Bucks Group's Topics
  • SGL East Anglian Group's Topics
  • South Leicester Observers's Topics
  • South Wales Group's Topics
  • SGL Surrey Observers's Topics
  • South Yorkshire Stargazers's Topics
  • Yorkshire Astronomers's Topics
  • Devon and Cornwall's Topics
  • West Midlands's Topics
  • Essex Cloud Dodgers's Topics
  • Essex Cloud Dodgers's New equipment
  • NLO and Planetarium's Topics
  • Astronomical Society of Edinburgh's Discussion
  • Dorset Stargazers's Topics
  • Hairy Stars Club (Comets)'s Tutorials and Guides
  • Hairy Stars Club (Comets)'s General Discussion
  • Hairy Stars Club (Comets)'s Observing Campaigns
  • Hairy Stars Club (Comets)'s Analysis results
  • Hairy Stars Club (Comets)'s Useful Links
  • Pixinsight Users Club's Pixinsight Discussion Forum


  • Astro TV
  • Celestial Events
  • SGL Calendar
  • Astro Society Events
  • Star Parties
  • WADAS's Events
  • Beaufort Club's Events
  • Astronomical Society of Edinburgh's Events
  • Dorset Stargazers's Events


There are no results to display.

There are no results to display.

Find results in...

Find results that contain...

Date Created

  • Start


Last Updated

  • Start


Filter by number of...


  • Start





Website URL







Found 15 results

  1. Many of you will recall when I purchased my APM LZOS 180mm triplet a couple of years ago I wanted to mount the scope on an Alt-Az but at 23kg for the barebones OTA and more than 1 metre in length, there was very little choice available that was up to the job. Fortunately APM themselves actually manufacture a seriously heavy duty Alt-Az mount called the AzMaxLoad. At the time a number of SGL members expressed some interest and more recently I have received a couple of PMs asking about it so I have finally got round to committing my thoughts into a review (work seems to have taken over my life over the last year, hence my inactivity on SGL). You can find the review on my astro-site on the link: http://alpha-lyrae.co.uk/2016/02/27/apm-azmaxload-mount-review/ To give a flavour of the size, here is the AzMaxLoad (on the left) next to my very capable Tele Optic Ercole (18kg OTA capacity). Quite a bit bigger isn't it!
  2. Hi everyone, about a month ago i got my first telescope. Wasn't sure what to get but i wanted something portable and easy to setup and use. After some internet "research" i decided to go for a refractor on a manual alt/az mount. The telescope was on a 50% sale so i decided to go for it , the Meade infinity 90. The package: The scope came in one big box, everything was inside. Included was the optical tube, the mount, 3 eyepieces (6.3mm, 9mm and 26mm), a 2x barlow lens, 90 degree diagonal, red dot finder, an eyepiece holder for the mount and a few manuals. The optical tube: The tube has a 90mm (3.5in) aperture and 600mm focal length. It looks and feels as a quality instrument, it has a small dew shield and the focuser is smooth when you move it back and forward. As expected the lens looks to be coated. It has a dovetail bar on it with 3 holes for screws. The mount: Light but stable, made of aluminium. It has 3 extendable legs, and 2 slow motion cables (alt/az). One screw to mount the tube on on top (adjustable back and forward). The eyepieces and barlow: All 3 are modified achromat eyepieces, the lenses are made of glass and are OK for the beginner, but i would suggest upgrading if you can. The barlow is bad i even think that the optics are plastic (not sure), it is usable if you don't have other options but this should be the first upgrade in my opinion. Observing: First light: The telescope arrived in the morning so the first thing i did after a quick setup was to adjust the red dot finder. I looked at some mountains about 20km away, the view was nice and very detailed using all eyepieces. Combining the 6.3mm with the barlow got me a bit blurry view, but the barlow in combination with the other eyepieces was ok. Night came and it was a moonless and clear night (only light pollution from the city i live in). I saw orion right infront of me, "marked" it with the red dot finder where i thought M42 should be and looked through the 26mm eyepiece. It was a bit blurry but after adjusting the focus i could see some nice pinpoint stars and also something fuzzy, i realized it was the orion nebula. After letting my eyes adjust to the view for a few minutes i started seeing 2 faint "wings" on both sides and in the center were 4 very tiny stars, i didn't expect to see that on my first night. I followed my target for about 15 minutes using the slow motion controls , it was easy to do. Also tried the 9mm eyepiece and with it the 4 stars were more easily seen but the faint clouds got fainter so i moved back to the 26mm. Next target was venus, i tried all eyepieces + with combination with the barlow. It looked like a very bright half moon without any details. When using the barlow the view was ok but purple glow was showing around the planet, without the barlow the purple wasn't noticeable. I also looked at the star Sirius which looked nice, bright and much bigger then any other star i could see that night. After Venus went down i decided it was enough for day one. Moon: I expected it to look good, but not this good. I was observing the moon for a couple of nights until it got full. I could see a lot of details at the terminator , with low and high magnification. When the moon was full it was very very bright and it looked best with the smallest magnification using the 26mm eyepiece. Jupiter and Saturn: I got 2 opportunities to look at these 2, the first time i think the "seeing" was bad. I could only see Jupiters 4 moons and the planet was a bright disc without any details at any magnification i tried. Saturn also wasn't very good, i could see the rings but they were blurry and "dancing" around. But the next time i had the chance to look at these planets the conditions were much better, first target was again Jupiter. With the 26mm eyepiece i could see a white disc with 4 moons.With the 9mm i could see the moons again but now the disc had very faint 2 bands without any color. The view was best with the 6.3mm eyepiece, the 2 bands were clearly visible and on the upper belt on the right side there was a small dark dot, i am not sure if it was anything . Next target was Saturn, event with the 26mm eyepiece i could see that it has rings, i switched to the 6.3mm right away and wow there it was, Saturn and its rings clearly visible, i even think i could spot the cassini devision, but it might have been my eyes playing tricks. I tried using the barlow on both targets but it was making the image blurry, but at this point i had purchased a higher quality barlow and the views were very nice with it , but the max magnification i could use that night was 133x, anything higher and the image was getting wobbly (probably that was due to the atmosphere that night). After that some clouds came in and it was time to get back to bed (got up just to see the planets in 4am). Conclusion: I think i got what i wanted, a small and very portable telescope for some basic amateur observing. I do recommend this telescope to anyone as a first telescope or even to an experienced astronomer who is looking for something light, portable and being able to set it up and start observing in 2 minutes. Also i would recommend you replace all of the eyepieces and the barlow. I got me a few plossl eyepieces and a nice barlow, it was worth it. Feel free to ask me anything regarding this telescope i will be more than happy to answer. Sorry for any spelling mistakes this review probably contains Also i am attaching a few images i took directly off the eyepiece using my smartphone (handheld). The Telescope The Moon: The Moon: Venus: Saturn: Jupiter:
  3. I bought this second hand, but it was almost untouched, and a relative bargain to boot. New it costs 1199 EUR from TS (approx. £1035 as of 08/03/2019 but who has any idea how this might fluctuate). Highlights: Apo air-spaced triplet with FPL53 Multiple focus positions thanks to removable tube segments 2.5” rack and pinion focuser, rotatable, dual speed controls, 6kg payload, with printed scale CNC tube rings and dovetail supplied Retractable dew shield First impressions: It’s a really nice box. Whilst it’s described as a ‘transport case’ the supplied storage box is sturdy and well made. Inside, the foam fit is precise bordering on tight. It’s actually mildly difficult to get the scope out of the box. Things get a little easier if you loosen the tube rights slightly, allowing for some tube rotation, and a longer term fix will be some straps to aid lifting the scope out vertically. The scope itself feels very well made, and is what I’m choosing to refer to as ‘reassuringly weighty’. At just over 4kg (without diagonal, eyepiece, or finder) there are definitely lighter options available, but it’s hardly a heavyweight. The finish is powered coat white, which looks and feels very nice. The focuser is very smooth (compared to my SW ED80) and feels pleasingly solid. I’m not going to be testing the stated 6kg payload any time soon, but I can easily believe it will be able to handle it. The dew shield is held in position with a single thumbscrew, and whilst it’s retractable credentials are clearly warranted, it only seems to extend a couple of centimetres. As it happens, this takes the overall length down to 450mm which was the very top end of my acceptable range in order to meet my ‘travel’ requirement. The focuser body also incorporates a finder shoe, but if you wanna finder then you have to supply your own as there’s nothing included. The idea of having additional tube segments is that you don’t have to rack out the focuser so far, and so improves stability. This also allows for multiple reducer/flattener options for imaging use. The TS website details the specific configurations using their recommended equipment which provide a faster f/4.9 option for sensors up to 36mm, or a full frame flat image at the standard f/6.6. I might be exploring these options later, but for now, this is going to be for visual use. First light: OK - this barely counts, but I was impatient. Predictably enough, first evening with a new telescope and it’s raining. But I did manage a pretty decent look at my neighbours TV aerial and chimney stack. They need some re-pointing. … The following evening (9th March 2019) was less rainy, but much the same for cloud, all but for about 30 minutes of relatively clear sky, interrupted regularly by patchy cloud. So still not great. However, my ambitious setup to allow for cooling paid off and I did manage a few minutes of actual use with a SW 28mm eyepiece. The Baader Zoom I also treated myself to for my travel use is frustratingly still not dispatched. And when I say set-up, I mean just carrying everything outside. I’m using this on the SW AZ-Gti mount, and a Manfrotto tripod I had already, so it’s very easy to pick up and take outside. I was using the scope with one of the two removable sections in place (this is how it is stored in the supplied case) and was able to achieve focus with a 2" diagonal without having to rack out excessively. Sirius was an obvious target to the south, and an easy hit. Brilliantly bright, as expected, and a blue-ish white colour. The upper half (the rest was below my sightline from home) of Canis Major was easy to see, with several of the background stars also visible. Despite the less than great seeing, the view was impressive. Stars were tight and there was no obvious chromatic aberration. Moving up to Betelgeuse, it’s orange-red brilliance was very pleasing, and again I was able to make out some of the fainter surrounding stars. Overall the view was very impressive, and bright. My only real comparison is with my SW80, and of course I now have over 25% more light, so that’s to be expected. But still, it makes an obvious difference. I wasn’t able to note any CA or distortion, and a quick full visible spectrum (no filters) star test reflected spot on collimation and no apparent astigmatism. Alas, the break in the patchy clouds did not last long, and I was soon packing up for the night and heading out for a beer. I’m looking forward to getting some more quality time with this kit, and who knows, I might even align the AZ-Gti next time and write a brief review for that too.
  4. Last summer whilst drooling over the beautiful looking telescopes on the Sumerian website I suddenly had the urge to ask permission for a 16" Canopus and to my suprise she said yes! Well it wasnt quite that simple as we then went through the whole haggling process as to how many pairs of shoes she could get if I got the telescope. I couldnt find alot of info about the Canopus model on the net so I started talking to Michael at Sumerian via email asking for details. He came back quickly with lots of details, advice and was very helpful right from the start. After a couple nights mulling it over I payed the deposit for a 16" Canopus with black paint with f/4.5 GSO primary and a OOUK secondary, I also added a couple extras like a 12x60 TS RACI finder and Telrad. That was the easy part, the hard part was waiting for 3 months for it to be built but I guess thats part and parcel of getting a custom telescope though. It was without a doubt the longest 3 months of my life! Fast forward to November 2nd and 3 months after the deposit was paid two very large boxes arrived from the Netherlands Putting it together was very simple, although full instructions were included I didnt really need them apart from when it came to the mirror cell....'where's the mirror cell??' A quick email to Michael and all was explained, as its a ultra compact dob it doesnt use an all metal mirror cell like I'd seen in Skywatchers/Meade's and OOUK's, Sumerian have there own design which I'm guessing saves on weight and bulk, a very nice touch. First light and the optics As its a custom scope you decide exactly what you want from the start and although the Mrs was happy in her mountain of shoes I thought it was pushing it a little too far to ask for a 1/10Pv Huygens primary so I settled on a standard GSO f/4.5 primary. So first light in VLM 6.4 skies and straight away I could see a problem as the views appeared very dim, you have no idea how disappointed I was! After some emails explaining the problem to Michael it was decided that the primary was very rough, it was returned to TS and a replacement was sent by Sumerian. I have to say that this was a stressful time for me but customer service from Sumerian was spot on and I cant fault them. Maybe the scope should of had been tested under the stars before it was shipped but in all fairness to them I was getting pretty impatient and just wanted the damn scope. So I've had the scope working since the start of December and the views it has given so far have blown me away, no need to really look for spiral arms in galaxies like I had to in my old 12", even though its only 4" gain in aperture it really has been worth the expense. Theres some sketches in my blog which may give a rough idea how objects appear in my EP. The build quality is very good, all bolted together the mirror box/rocker box is very solid and there is a very small amount of vibration through the truss poles when in use, this is still far less than my old Skywatcher though. I was a little worried that the black paint would chip or show any little knocks but even with my accident prone hands its still like new after a couple months. The Alt/Azi bearings are sooooooo smooth when in use, 10/10 here. It has three small primary cooling fans on the rear of the mirror box, I've had these running and used mags of x300 and cant see any vibration. It has a secondary heater powered by 3 AA batteries which lasts for around 24 hrs. The shroud you see in one of the pictures below was bought separately from Heathers Shrouds in the US. Total weight is 33kg which is 9kg lighter than my old 12" Skywatcher and its also smaller in size when broken down to transport and can fit in the boot of my Astra. Price? See the Sumerian website. I honestly can say that I cant think of anything I'm unhappy with, yep if I had more money at the time a primary a little faster and from one of the better mirror makers would make it better but thats something I may look into more in the future. This is a scope that I plan on having for many years to come and I can completely recommend the Canopus to anyone.
  5. Daystar Quark Chromosphere Review – A New Era in Amateur Solar Astronomy? Until recently, it’s been very expensive if you want to view or image the Sun in the hydrogen-alpha wavelength using a relatively large aperture such as 100mm. For example, a Lunt 100 dedicated h-alpha scope with B1800 blocking filter and Feathertouch focuser is likely to cost in excess of £7,000. In 2014, things suddenly changed. Daystar Instruments, who have over 40 years of experience in solar filters, released a new product, the Quark. Costing less than £1,000, this new type of device can be used with many refractors, turning them into h-alpha solar telescopes. Enter the Quark The Quark works in a different way to the regular dedicated h-alpha telescope. Daystar refers to the Quark as being the world’s first h-alpha “eyepiece.” It’s not really an eyepiece. Typically, you place it between the diagonal and your actual eyepiece or camera. The Quark has a professional look and feel with an aluminium housing. It comes with a mains unit for power. I prefer to use a USB battery pack and longer cable. Inside the Quark is a 4.3x telecentric Barlow. This helps to ensure that light passing though the Quark is reasonably parallel, which is required for good performance. The Quark requires power and about ten minutes or so to warm up. This is because the tuning of the Quark’s etalon is controlled by the heating of an internal cavity. For energy refection, many refractors can be used without the need for an expensive front energy rejection filter (ERF). The manual states that if your scope is under about 120mm of aperture, you can use a compatible UV/IR cut filter in front of the diagonal instead of using a front ERF. However, a front ERF must be used instead of the UV/IR cut for telescopes with an integrated rear field flattener or Petzval lens or if over about 120mm. See the Quark manual for more information and check with Daystar if you’re not sure what you need. Quark Basics The Quark unit I am reviewing is designed for use with refactors in the range F4- F9. Daystar now also sells a Combo Quark for off-axis use with SCTs. The Quark comes in two flavours, both priced £899 at time of writing: ‘Chromosphere’ and ‘Prominence.’ The Chromosphere version (the one I am reviewing) is specified to have a bandpass of 0.3 to 0.5 Angstroms, while the Prominence is 0.6 to 0.8 Angstroms. In short, the Chromosphere is best for surface detail and gives more contrast on the disc, the Prominence is best for prominences, but there is crossover between the two. Depending on your setup, it is possible to use a 0.5x reducer with the Quark to bring down the focal length if you wish. Because of the integrated Barlow, there is plenty of backfocus available. The Quark comes with a main supply included. I recommend using a rechargeable USB battery and long cable instead for greater convenience. Daystar sells a battery pack as an extra, though some users have noted that it bears a striking resemblance to much a cheaper battery pack available from Amazon! Eyepieces are another consideration. Because of the Quark’s integrated Barlow, you need long focal length eyepieces. Daystar recommends Tele Vue Plossls, specifically the 25mm, 32mm and 40mm. However, some Quark users have reported excellent results with Vixen SLV eyepieces. The integrated Barlow can also affect how much of the Sun you can see in the field of view. Full disc viewing is possible with refractors up to about 450mm focal length. Lastly, the Quark has an integrated 12mm blocking filter and offers 21mm of clear aperture filter. Getting Up and Running The Quark may be relatively cheap, but it looks professional, with its anodised red and black aluminium housing. The 1.25” eyepiece holder includes a brass compression ring. This is a nice touch though in practice I have found the compression ring to be sticky. There were a few worrying moments when my camera or eyepiece snagged on an edge and I was concerned that I might drop it! Fortunately, the eyepiece holder unscrews easily and can be replaced. First Light Optics sells an adapter for the Quark that enables T-threaded accessories to be fitted. Using one of these adapters, I swapped the Quark’s eyepiece barrel for a Baader ClickLock 1.25-inch eyepiece holder. Much better! The Quark has a combined 1.25” and 2” nosepiece, so you can use it as is with a 1.25” or 2” diagonal. If you use it as 2”, don’t forget to take the dust cap off the 1.25” nosepiece, or you may see smoke rising out of your Quark! First Light with Al Nagler’s Briefcase Telescope I decided to be cautious and gradually step up in aperture. First up was my smallest scope, the Tele Vue 60. Its focal length is just 360mm, so this looked a good option for full disc viewing with the Quark with room to spare. To set up the Quark, I placed a UV/IR cut on the front of the 1.25” diagonal, slotted the Quark in the diagonal, hooked up my battery pack, and waited for the Quark’s LED to turn from yellow to green. After about 12 minutes, it was green for Go! Unfortunately, there was lots of patchy cloud around and conditions were not ideal, so it was hard to tell just how well the Quark was performing. I found that turning the tuning knob from central to a few other positions in clockwise direction improved the view. When I changed the tuning, the Quark LED turned yellow and it took a few minutes or so until the LED turned green again to indicate that tuning had been reached. I was able to carry on observing while the tuning changed, the view was stable and I couldn’t tell anything was changing, it was too gradual for my eye to detect any change in real time. Another reason why it was hard to judge the view was that I had no towel with me! With the Tele Vue 32mm eyepiece I was using, I had to have a gap between my eye and the eyepiece due to the eyepiece’s very long eye relief - I later bought an eyeguard extender for this eyepiece to make it a snugger fit, and bought two extenders for the 40mm! Second Light - Throwing in the Towel I was better prepared for the Quark’s second light. This time I had a towel at the ready and a little more aperture to bring to the party: the Tele Vue 85. The first view was glorious. The spicules at the edge of the Sun were much more clearly defined than with my Solar Max 60. Contrast was better than I had expected. I was very used to views with both single stacked and double stacked SolarMax 60’s and without doing a direct comparison, the contrast of the disc felt middle of the road – more contrast than with my single stack SM60, but not quite as much as with the double stack. Also the swirls and whirls around active regions showed considerably more detail than I have ever seen with a 60mm scope. Proms appeared to show a finer structure than usual, a little bit like using a bigger dob to observe galaxies in Leo. The Quark was making the extra aperture of the TV85 count. And what really struck me was that there was no obvious sweet spot whatsoever. With the SolarMax 60, there is a considerable sweet spot and often I nudge proms towards the centre of the view for a better look. With the Quark, proms looked just as good towards the edge of the view. For the £795 I had paid for the Quark, I was impressed. It was not all good, though. Unfortunately, there were distracting flaws in the eyepiece view: in particular, a bright spot and two fold-like marks that moved with the view. The unit would have to be returned. The retailer, SCS Astro, kindly allowed me to carry on using this Quark for some weeks while I waited for a replacement. This was terrific news: this Quark worked very well for imaging, the flaws did not show up on the small camera chip. Thank you, SCS Astro! Plossls at Dawn - Quark and TV60 Versus Solar Max 60 Single and Double Stack The big deal for me about the Quark is that it makes larger aperture solar h alpha more affordable. However, the reality is that some folks will be deciding between a smaller dedicated h alpha scope, like the Lunt 50 or a second-hand SolarMax 60, versus the Quark. They are a similar price. So, can a Quark take on a dedicated scope at the same aperture, never mind in the larger scopes? I had two SolarMax 60’s at the ready to find out. One was single stacked (SM60 SS), the other was double stacked (SM60 DS). I grabbed some Plossls for the Quark, and Radians for the SM60’s. First up to challenge the Quark was the SM60 DS. The SM60 DS landed an instant blow to the Quark – it gave better contrast. Very nice indeed. There was a huge filament dominating the disc on this day, and it was gloriously dark against the surrounding brighter parts of the disc in the SM60. The filament jumped out that little bit more. Also, plage showed more contrast with the SM60 DS. Another win for the SM60 DS is that it did not show the double limb, whereas the Quark did, which is to be expected as the double limb shows in single stack systems (including my SM60 SS). The double limb is caused by light from the photosphere leaking through. Personally I don’t mind it, but a purist may prefer a double stack system that eliminates it. The Quark soon bounced back and jabbed the SM60 DS firmly in the eye. The Quark had no obvious sweet spot. The full disc view with the Quark shows sharp, well-defined proms and tiny spicules to the edge of the field of view. As mentioned before, the SM60 has a considerable sweet spot and proms looks best more central. Over the months I greatly enjoyed the impact of full disc views especially on days with lots of proms where detail is so good all across the entire view. All in all, I couldn’t split the Quark and TV60 vs SM60 DS. It was a case of no obvious sweet spot vs better disc contrast. Next up was my trusty SM60 SS, which I had used a great deal for grab and go. Part of me was rooting for my faithful companion. Round one was contrast, and it was close. Too close to call. In terms of fine detail, the Quark had the edge, I could see a little more structure with it. And then there was the sweet spot again. The Quark was the champ here, with its lack of any obvious sweet spot. The final bell rang, it was a win on points for the Quark, the lack of a sweet spot had carried it to victory. NOTE: Over the coming months, one thing puzzled me about the Quark: In my other telescopes, contrast seemed significantly better than with the TV60. I eventually tried using the Quark and TV60 with the Quark in a straight through configuration (UV/IR cut in front of the Quark) with the diagonal after the Quark. This really improved the contrast, and at higher magnification, I could see much finer detail in active regions than I have ever seen with the SolarMax 60. Wow! If the Quark is not lined up well with the light path, this can lower the performance of the filter. If your Quark is not performing well, try using another diagonal if you have one (don’t forget the UV/IR cut if you are using one). If trying a straight through configuration, be sure to check the advice from Daystar for safe usage. Time for the Big Gun - Equinox 120 At last it was time to use the Quark with the scope I was most looking forward to testing it with: the Equinox 120. I felt that this was about the largest aperture I could use with the Quark without having to buy a very expensive front energy rejection filter that would roughly double the cost. I used an Astronomik 2 inch UV/IR cut on the front of the diagonal. The first thing that struck me about the initial view was: wow, that is a small piece of the Sun I am looking at! Secondly, conditions were great, I wish I had set up for imaging! Spicules were that little bit crisper and clearer than with the Tele Vue 85. Smaller proms revealed much more "character" than at 60mm. In particular, there was a very small looping prom on display. I could see the separation from the disc clearly as it arched over the limb. Smaller proms like these typically show little detail at 60mm and it feels like there’s a gap and a loop, but it’s not clear to see. With the 120mm it was crips and beautiful! Swirls of detail around the active regions came more alive than at 60mm, filaments showed finer structure and complexity at the higher magnifications. There was, quite simply, detail everywhere I looked. I was greatly impressed. One of the downsides of the Quark versus a dedicated scope like the Lunt 100 is that you cannot view the whole disc in one go in larger scopes. Although it’s possible to use a reducer with eyepieces to view the Sun at a lower power, I didn’t feel the need anyway. At lower mag I could not see as much fine detail, and fine detail was why I was putting the Quark in a 120mm scope in the first place. I wouldn’t be pining to see the full lunar disc if using a 14 inch SCT. Quark and big scope is about close-ups. I would be using the Quark with my TV60 for grab and go, so I would get plenty of low power full disc then. Life with Quark Since these early views in 2014, I have used the Quark many times in four different telescopes. Just like white light with a Herschel wedge, I find it convenient to be able to use the Quark in different scopes. The Quark certainly works as a grab and go for me. On an unusually sunny holiday I managed 17 straight days of using the Quark and TV60. I used a mini giro mount and tended to power up the Quark indoors while having breakfast so that it was ready to use afterwards. Perhaps a fast 80mm would make more sense, to still allow full disc and to reveal finer detail at higher magnifications, but I love the portability and character of the little scope and for me grab and go is about fun and enjoyment, not the best view. Also, the sleek black TV60 does not draw attention to itself, unlike my old gold SolarMax 60! My favourite scope for imaging is the Equinox 120. I normally use a 1.25” 0.5x reducer, a cheap £20 or so buy from Telescope House. My favourite scope for observing in the Skywatcher ED100 DS-Pro. I find it nearly matches the 120mm for detail, yet is comfortably ahead in detail than my 85mm scope. It’s also nicer to use on my giro scope than the 120, being considerably lighter. My Tele Vue 85 also gets Quark time. I tend to use it as a compromise scope. If I’m imaging and it’s a bit windy, I will drop down to it from the 120mm. Or if I just want a quick view, sometimes I will grab the 85 instead of the 100, as it’s a far smaller scope and the view is certainly a step up at higher magnifications than with my Tele Vue 60. When I first heard about the Quark, my two main concerns were the integrated 4.3x Barlow and the need for power. In practice, I haven’t found these to be much of an issue. A 0.5x Barlow tames the focal length for my needs. I could probably push the Quark more than I do, I was impressed in one session when I forgot to put the reducer on my ASI174 and the view on screen looked very good and do-able. I also like that the Quark’s Barlow is inside the Quark, protected from the dust that my regular Barlows always seem to attract! I found the power requirement okay, and a small price to pay considering the relatively low cost of the Quark. A portable battery pack means I can power up the Quark indoors or while I am getting out the mount etc. I use a long cable and then run this up the telescope tube and down the side of the mount, so it doesn’t tend to get in the way. The warm up time of ten minutes or so makes no difference to my imaging with the Equinox 120. It takes me at least that long to get set up (rough alignment, setting the time etc. on the handset, moving to the Sun, getting the camera ready, and so on). The time it takes for the Quark to reach a new tuning also hasn’t really troubled me. I have used several Quarks and once I have found a tuning that I like, I just keep it on that. If you are a more advanced user, perhaps this is more of an issue if you want different tunings such as to show Ellerman Bombs. There has been a lot of talk since the Quark came out about the bigger scopes being more demanding on the seeing. For visual, I normally use my ED100 and it’s fine, it shows far more close up detail than with the 60mm scope. If the seeing conditions are very choppy, which is fairly rare (I tend to do mornings when conditions are usually better), I have no great wish to see it at 60mm either, I prefer leave it a while to see if things settle. Out of my four Tele Vue Plossls, my favourite to use with the Quark in all four scopes is the 32mm. I am content just using this eyepiece. Now and again I like to sneak in closer with the 20mm or 25mm, but really, things look good and detailed already with the 32mm, I could get by with this one eyepiece alone. However, I would consider the Vixen SLV instead if buying again following some reports on excellent performance from other Quark users. Quark Issues Unfortunately, I have experienced a number of issues with the Quark. In total, I purchased four Quarks from three different retailers and today I have two out of the total of eight Quarks that I have used. Here is a brief summary of how I got on with them. Quark 1: Performed excellently for imaging but showed defects in eyepiece view: small bright spot and two dark fold-like marks in eyepiece view. Returned for replacement. Quark 2: Replacement for Quark 1. Large scratch-like mark in eyepiece view. Returned for replacement. Quark 3: New, second purchase. Wanted two Quarks, plus cover in case of further problems with first Quark purchase. Quark gave very uneven illumination (see small flat image below) and loss of detail over large parts of eyepiece view. Was part of a problem batch apparently. Returned for refund. Quark 4: Replacement for Quark 2. Performed fine for imaging, accepted. I still own this Quark. Quark 5: New, third purchase, still wanted second Quark. Accepted this Quark, to use for imaging. Quark developed fault within 12 months (view looked somewhat like white light). Returned for warranty repair/replacement. Quark 6: Wanted third Quark, for wife’s use, mostly visual. Quark gave excessive glow in eyepiece view with inferior views of proms. Returned for replacement. Quark 7: Replacement for Quark 6. Performed well, clean view, accepted. Quark 8: Warranty repair/replacement for Quark 5. Appeared to be replacement (different barrel). Many splotches over much of eyepiece view. Returned for refund as agreed by retailer. Verdict The Quark is a brilliant device that can dramatically cut the cost of viewing or imaging the Sun in hydrogen alpha in larger scopes than 50/60mm, and it offers an interesting alternative even if used in smaller scopes. In my experience it gives reasonable contrast, though not quite as much as a double stacked dedicated scope. The Quark shows no obvious sweet spot. At apertures of around 100-120mm, the Quark gives remarkably detailed views at higher magnifications. I highly recommend apertures of 100mm or more. For visual, I found the Skywatcher ED100 DS-Pro to be a superb match. Although the Quark may look less flexible than a dedicated h alpha scope because of its integrated Barlow, you can tame the focal length to some degree using a 0.5x reducer. The Quark gains some flexibility from being able to be used in different telescopes, such as 60mm for full disc (with my setup, full disc imaging in four tiles versus single tile for SolarMax 60) or 100mm for close-ups. If you want to travel light, it can be a plus that you can use the same telescope for hydrogen alpha (Quark), white light (Herschel wedge) and regular astronomy. The Quark can look like a no-brainer if you want to use a large telescope around the 100-120mm mark and your funds do not stretch to the likes of the Lunt 100. However, all things considered, with a heavy heart I cannot recommend the Quark. I have experienced a number of issues. From a total of eight Quarks used, I now have only two of them. I would not buy a Quark now. I would be thinking, okay, if I buy from a good retailer, I can return the unit promptly if it does not meet my reasonable expectation. But what if I am happy with it, accept it, and it breaks after say ten months? What if I send it back to the USA, wait some weeks for a repair/replacement, and it is replaced with a Quark that performs very differently to the one I had accepted, and it shows distracting flaws in the eyepiece view? This has already happened to me once - see Quark 5 and Quark 8 in Quark Issues, above. I requested a refund as I considered that the repair/replacement had failed. I understand that another replacement was offered by Daystar. The retailer, SCS Astro – who have been very supportive throughout – kindly agreed to a full refund. Thank you, SCS Astro! While the close-up views at 100-120mm can be intoxicating, I recall that I had no problems with my two SolarMax 60’s. Next time out, I intend to take a very close look at the Lunt 50. It is returning some excellent full disc images and I have enjoyed a number of views though Lunt telescopes. Perhaps less is more sometimes when it comes to aperture. NOTE: You can read about SCS Astro’s experiences with the Quark and customer issues here: http://www.scsastro.co.uk/ Quark Cons Less contrast than a double-stacked dedicated solar h-alpha scope. Full disc not visible in scopes above about 450mm focal length. Integrated 4.3x Barlow ramps up the focal length for imaging, though depending on camera chip, you can use a 0.5x reducer. Eyepiece selection is more fussy, 25-40mm Tele Vue Plossls are recommended. 2” eyepieces do not fit by default, though a replacement 2” eyepiece holder is available. Power is required, in practice I found this to be less hassle than it sounds when using a battery pack and long cable instead of the included mains unit. A battery pack is available from Daystar though be wary of the high price compared to alternatives. Quark needs to be powered for about ten minutes or so before use. Quark needs a few minutes to change to a new tuning. Quark Pros Costs far less than a dedicated 100mm scope. No obvious sweet spot. Use the same scope for white light/regular astronomy as well - ideal for travelling light. Use different scopes to match your current needs, e.g. 80mm for grab and go, 120mm for close up imaging. The integrated 4.3x Barlow is shielded from dust. Quark Images
  6. IAS 2019 Review - Friday 15 November My second show (first was last year), as before got there on Friday 15th, soon after 0900hrs. Despite the weather, seemed to be fairly busy in the main hall. Had a few good discussions with different vendors, 365 Astronomy in particular. Even the guy on the Vixen stand near the entrance, remembered me from last year! RVO had a whole hall to themselves, not really sure why? They did seem a bit 'lost' in there. All that space and not much kit... Again, there to 'window shop' only, but still managed to spend £90! Got a good price on a WO 1.25" Dura-Bright Dielectric diagonal. (Thanks Widescreen) Best online price I'd found, prior to the show, was about £100 inc. postage/delivery, so saved a tenner! Restaurant was a big improvement over last year. Coffee was OK, lunch was pretty good too. Choice of Fish 'n' Chips or Cottage Pie. All gone by 1345hrs... All in all a good day. Looking ahead to 2020, might make three in a row! Chaxastro "Humour is reason gone mad" Groucho Marx
  7. Hi all, Been a while since I have been on the site – work has been really busy these last 18 months, and although it’s still manic, things are slowing down a bit!! Viewing my previous posts, you will see that I was in the market for a new scope to adorn my EQ3-2 mount that I had purchased ages ago now!! Well, things didn’t turn out as expected, and while I am still hoping to get a scope, hopefully at Christmas if Santa is kind to me (I have been a good boy lol!!) I decided to get a pair of Binoculars to fill the gap! Budget was tight, and I did want a pair of larger aperture bins. A lot of reading up on the internet, and I settled on the Celestron Skymaster 20x80’s. I already have a pair of 10x50’s so was after something with a bit more power, and larger objective’s. The skymasters seemed to fit the bill, and the price was right as well! I dropped into Rother Valley Optics with my cash on the off chance they would have a pair in stock – they didn’t, so I left my details, and less than 24 hours later, Adam from the shop called me to say they had a pair in! I drove over to their shop, tried them out outside the shop, as I had read that some pairs are known to have collimation issues. These where perfect, so I parted with my £99 cash and went home with them! First class service from RVO, and I will be using them again when it comes to getting my scope – thanks guys! So, onto the bin’s. They came double boxed up, and within the branded box inside the plain box, the bin’s were securely packed in foam and wrapped in plastic. They come with a basic carry case, which won’t protect them from hard knocks, but will keep the dust off them while not in use. The eye pieces are protected by a one piece cover, while each large objective is covered by its own, separate cover. There is also a basic neck strap, but it appears quite flimsy, and I won’t be using it. The bins have a built in tripod adaptor, on an adjustable slider, meaning they can be securely attached to a tripod and balanced up. Weight wise, they tip the scales at just over 2.6kg. This isn’t hugely heavy, and while I did use a tripod for some observing, when I wanted to look at things nearer the zenith, I hand held them, and did so for quite some time. I didn’t feel they were overly heavy, even after prolonged use. It seems that new scope curse also affects owners of new binoculars, as I had to wait 5 days for clear skies!! I went out at about 10:30pm into the back garden, and while the side of house has a street lamp directly over the hedge, round the back its cut off, and quite dark. I began by finding M31, which at is currently nearly at the Zenith. I could see the central core clearly, and with some averted vision, make out some finer details in the disk. Moving on to M45, the Pleiades, that was just rising over my neighbours fence – what a sight!! Even though it was quite low down, the cluster filled the view, and I could see loads of fainter stars within it. Moving through the Milkyway, the view was filled with thousands of stars and star clusters!! I was really impressed. I intend to go to a dark sky site up in the Peak District, just north of Ashbourne when time and the weather permit, to get some proper dark sky viewing in! I have not yet been able to look at the Moon or any planets through them – the Moon hadn’t risen by the time I turned in, and is now a very small waning crescent. I will have to wait a bit longer, and will update the review once done. Mars was up, but low in the sky, and due to the street lights, swamped with LP. With terrestrial viewing, they provide bright and crisp views. While there is some CA when looking at things with bright edges, general viewing wasn’t affected in any way. I plan to take them to my local nature reserve to test them out on some wild life as well. I am also a bit of a plane fan, and when time permits I park up near East Midlands Airport to watch the aircraft coming and going – these will be great for that, set up on my tripod for easy viewing! Conclusion – the Skymaster 20x80’s are a decent pair of binoculars. While they don’t have the build quality of more expensive ones, treated well I can see no reason why they won’t last for years. They actually come with a 5 year Celestron guarantee anyway! For causal use when you don’t want to set up the main scope I think these fit the bill nicely, and I would recommend them to anyone. Cheers all Nige
  8. I am looking for user reviews about the Starlight Xpress Trius 825 Monochrome camera. Tried Google, but nothing so far. I'd also appreciate a general review of the Trius series of cameras. May help me in making an informed decision. Is the cooling as good as they claim? -50C below ambient?
  9. I visited the International Astronomy Show in Warwick the other week. Just inside the door there was a young chap selling dew control products. The gear was lightweight and relatively inexpensive, so I thought I'd give it a try. I picked up one heater band (for my Esprit 120) and one 4 channel controller. The controllers he had at the show all had a 2m power cable. I said I would have preferred another metre. Tim (the young chap) said it was not a problem. He would make one with a 3m cable and send it out to me. He obviously posted it first thing Monday morning because it arrived on the Tuesday. What I liked about the unit was how lightweight it was. It also had a belt-loop sort of thing attached to the back. This allowed the elasticated part of the heater tape to pass through, so that the controller could be fixed to the scope itself. Here is how I have done mine: The controller works off one button (the small red button just under the printed text 'Quad Channel Dew Controller' on the case). When you power up, Output 1 is illuminated. Press and release (less than 1 second) to cycle between 0, 20, 40, 60, 80 and 100 percent output. There are 4 lights: 0% power = no lights, then each light comes on singly for 20, 40, 60 and 80 percent. All four lights are illuminated at 100% power. To switch channels, hold the button down for a bit longer (more than a second) and release. It is remarkably simple to use. With my other dew controller there seems to be a bit of 'uncertainty' as to whether or not the phono plug is properly seated. With the Dewcontrol unit the seating is extremely positive. One possible downside (or upside depending on your point of view) is that, when you power down, the unit does not 'remember' your settings. You start from zero power in each channel at each power up. This has caught me out once, unfortunately, but I will soon get used to the new way of doing things. I am very pleased with the unit. It is lightweight, inexpensive and works well. It is good to have a range of alternatives and this one is from a UK manufacturer. The heater tape worked just fine too. It was made by the lady who co-worked the stall with Tim (her name was Barbara). It seemed to be high quality. It is hand sewn. It worked straight away (unlike a top-end brand I bought a couple of years back that I had to pick apart and fiddle with). I am not sure if these are the same tapes that Tim sells on his website. My wife recalls that the brand of heater tape was W&W Astro - and Barbara's website is here http://www.dewheater.com/. I have no connection with Tim whatsoever. When looking up some info (his name for example) for this review, I found that his website was a little difficult to locate - if you are interested it is http://www.dewcontrol.com/. I may get one of his two channel units for my more portable setup. Steve M
  10. I have had my Hyperion Zoom Mk.III for quite a while now and I was wondering, if I should review it here, because what there is to say about an eyepiece, really? You just shove it into your focuser and look down the glass end, right? Well, since the Hyperion Zoom is effectively 5 eyepieces in 1 (I don’t really think it’s that big of a deal), it is not really a “static” piece of equipment, and there is lot of “accessory” for it, I thought I’d give it a try. Optics Optically, the eyepiece is a “seven element eyepiece, with multi-coated optics for remarkable sharpness, contrast and colour correction.” I am in no way an expert in optics, but I have to say that the quality of the image outperforms my pervious eyepieces, primarily in sharpness and contrast. I even had a 12mm Hyperion normal eyepiece for some time, and when compared, the views through the two were pretty much the same. Even in my F/5 dobsonian, the image distortion at the edge of the field of view is really not bad - though there, I do not really notice it that much; it is only when I zoom out to 24mm focal length that the distortions become really noticeable. There is a shaft, sticking out of the body of the eyepiece, in which the movable part of the zoom mechanism moves in and out, and I simply never get tired of the action-packed zoom action. One problem can arise though, and that is that any imperfections on the surface of the lenses inside the eyepiece can get, due to its zoom nature, visible at some point - that way, I once noticed a quite large piece of dirt inside the optics, which came into focus in 12mm position - this was really bothering me, because it was extremely disturbing, especially when observing the Sun or the Moon. Luckily, somehow, the piece of dirt disappeared (after bumping the EP gently on the table), so there is no need for returning it to the supplier. The piece of dirt did not appear again ever since. It is said that normal eyepieces outperform zoom eyepieces, but I am not so sure. Well, on one hand, you get a narrower field of view, that is true, but the quality of the image delivered (with Hyperion Zoom in particular) is really very good and if you are not traditionalist, or fond of ultra-wide fields of view, this age-old paradigm suddenly gets null and void and a concept of having half a dozen eyepieces suddenly gets, well, stupid. Having one decent Zoom eyepiece just seems more practical. Personally, since I have bought my Hyperion Zoom, I have not felt any need of buying a new eyepiece (for the particular range of magnifications), because it embodies everything I do (and will) need at the moment. Furthermore, the edges of the lenses are apparently blackened, and the EP’s construction allows very little or practically no reflections of brighter objects. Accessory The Hyperion Zoom comes with a wide range of “accessory”, if that is the right word; basically you get two different rubber eye cups (I even got a rubber eye shield, but I am not sure if that was part of the package, or a gift from the supplier), and both allow you to use the eyepiece comfortably, even when you are a glasses wearer; the eye relief is generous enough to allow that, though I am sure there are EPs with better eye relief than Hyperion Zoom. Furthermore, you get adapters for both 2” and 1.25” focusers. I personally prefer to use the 2” one with my 300P, because it feels more firm and solid, and the inside of the 2” adapter is “baffled”, which seems nice. One thing that I do not really get is that when you use 2” adapter, you can’t use 1.25” colour filters at the same time. The shaft, in which the movable part of the eyepiece moves in, is of just the right diameter, and it even has a thread on the end of it; but somehow, the boffins at Baader did not think to make it standard 1.25” filter thread, and that is a pity. I think it would be wonderful to have a freedom of filter choice, but that way, you can only use 2” filters with the 2” adapter and 1.25” filters with the 1.25” adapter; too bad. Perhaps, they will address that on Mk.IV. Furthermore, you get a wash of dust covers, just in case you use any of the possible combinations of eye cups and adapters, which means you can easily lose one if you are not careful. The eyepiece also comes with rather elegant leather-ish bag for you to store it in, which I, think is a rather nice touch. Usage The most prominent feature of this Zoom eyepiece is its…well…zoom capability. The eyepiece has click stops at 8, 12, 16, 20 and 24 mm focal lengths, which means that it can deliver a wide range of magnifications, depending on your telescope’s focal length. I for instance have a 305/1500 dobsonian, which means that I get 62x, 75x, 94x, 125x and 187x magnifications, which is a range good enough for most objects up there. It should be said that the EP’s field of view varies with focal length - basically, the shorter the focal length, the wider the field of view; the longer the focal length, the narrower the field of view (it’s actually 68° FOV with 8mm and 50° FOV with 24mm). Of course you can use any focal length between the click-stop position as well. Furthermore, though advertised, the eyepiece is not perfectly parfocal (meaning that it holds focus at all focal lengths), which means you have to refocus every time you change the EP’s focal length. I know that there are eyepieces with better FOV that are perfectly parfocal, but these can get way more expensive than the Hyperion Zoom. It is fair to say that I have heard that some people find their zoomy Hyperions stuck when it’s freezing out there, and thus the eyepiece needs regreasing. However, I have used mine in temperature below -7°C all night, and although the zoom action felt more stiff, it did not get stuck even a bit, so if there really is a problem with it freezing solid, I reckon it is an effect prominent overtime. However, the Hyperion Zoom is not that cheap - it costs roughly the same as two fixed focal length Hyperion eyepieces, which is quite a lot, but then, you get a variety of magnifying power in one eyepiece, and it is just great not having to change the eyepieces all the time, every time you want to try different power. One of the best things on this eyepiece comes with it zoom capability - without having to change the eyepieces, you can toy around with magnifications to see which magnification delivers the best contrast on the object you are looking at - this is due to the fact that the contrast of the background often changes with magnification (e.g. when you zoom in, the background gets darker), which means that some dim objects can miraculously pop up, or seem more distinct. There is a slight issue with having to refocus all the time but when you concentrate on some fuzzy blob, you see the change in contrast when you change magnifications, even though the image is not perfectly focused. This gives you an ability of very quickly and easily changing the views through your telescope to see which one fits the situation the best, and I think this is one of the main advantages of any zoom eyepiece. The eyepiece itself is quite bulky and heavy (when compared to standard 1.25” eyepieces), which on its own is ok - you get a good sense of its build quality and heftiness - but it becomes a problem when you want to use the eyepiece with some more basic, entry level telescopes. For instance, I have a Skywatcher 114/900 with a plastic 1.25” rack-and-pinion focuser and it really struggles with the Hyperion Zoom. The eyepiece is so heavy that it bends the focuser tube this way and that way and upsets the balance of the whole setup considerably. This means that perfect collimation, is, at this point, really unimportant. I have yet to try the eyepiece in my Firstscope 76, but I reckon it will handle the eyepiece a bit better, because its focuser feels slightly more robust. Upsides “5-in-1” zoom concept No need for eyepiece swapping Zoom ability lets you find the ideal contrast magnification Decent build-quality, big and robust Wide range of accessory (adaptors, eye cups) Good contrast and sharpness, comparable to fixed focal-length Hyperions Smooth zoom action, even in low temperatures Good eye relief Good for afocal projection No inside reflections Downsides Narrower field of view with low magnifications Inability to use 1.25” filters with 2” adapter More expensive than regular eyepieces Dirt inside the optics can get into focus, which is really annoying Apparently can freeze solid in sub-zero temperatures (not proven) Heavy Not suitable for entry-level telescopes
  11. Background The late Thomas M Back developed his planetary series of eyepieces working with Burgess Optical. Those who want to know more about Tom and his works might like to read this 2006 report: http://www.cloudynig...hp?item_id=1549 . Tom was enthusiastic about the eyepieces and wrote about the 4mm on 21 October 2005 as follows: "I first did a bench test with my Strehl .997 TMB 100mm f/8 SD apochromat, on the autocollimator. As you may know, I was very happy with the performance of the prototype of the 4mm. The production model is as good or better. The Airy disc was textbook, the off-axis aberrations were as low as any eyepiece I have tested in this field size and focal length, and the contrast and sharpness was superb."At the time these eyepieces were a radical departure, at $99 much cheaper than, but similar in specification to the Televue Radian and Pentax XL, which were market leaders. Tom set high standards for his eyepieces as in this claim: This is the first wide angle, long eye relief eyepiece that has the sharpness, contrast, and lack of scatter that the best orthos have...These are bold claims which I will attempt to address in this review. In the years since, there has been extensive discussion about their quality. Some changes have been made and some are now labelled Planetary II, but I am not a historian so will concentrate on the features and performance of these four currently available eyepieces. Eyepieces under test The four eyepieces that I have in front of me are all of 4mm, to the same optical design and I think they are representative of those currently on the market, as follows: TMB ® Optical Planetary II, hereinafter TMB ®, which is now only available from Astronomics in the US, though mine was bought in 2012 from High Point Scientific who were then also distributors. This is the only range authorised by the Estate of the late Thomas Back and on which royalties are returned. Astronomics will ship to the UK and these eyepieces were on sale at $40 at the time of writing, though only the 5mm, 6mm and 9mm were in stock. Clearly taxes and carriage would add significantly to that price. TMB Optical Planetary II SW, hereinafter TMB SW, is widely available including from a number of UK dealers, from one of whom mine was bought in 2011. I have four eyepiece in this series and for some time they formed the backbone of my eyepiece collection. At the time of writing this model is listed on the Burgess Optical website. The range includes 4.5mm and 7.5mm models, which were not part of the original set. They are quite widely available in the UK price for about £50 or slightly less. Teleskop-Service HR Planetary, hereinafter TS HR 60°, is available from Teleskop Service and a number of other dealers, some which are in the UK. Markus Ludes of TS has written that the design was supplied to him directly by Tom Back. The 9mm has a revised barlow arrangement and there are additional 15mm, 20mm and 25mm eyepieces to a similar design. My example was obtained second hand. The price in the UK from Modern Astronomy is £49. Sky-Watcher Planetary 58° UWA, hereinafter UWA, is widely available from Sky-Watcher dealers, but has no Sky-Watcher mark and the eyepiece appears to be identical to those sold under the BST and Olivon labels and formerly known as "TMB design". At the time of writing Sky-Watcher only offers the 2.5mm, 4mm and 5mm but other suppliers offer the same range as for the TS HR above. For some time I owned the 15mm and 25mm. The Sky-Watcher models are widely available and cost about £40. Overview These four eyepieces are very alike so I shall cover the similarities in design and performance first and differences afterwards. The optical design is quite novel but there is no patent that I can see. The the names TMB and TMB Optical are US trademarks. The design is certainly not a Plössl (four lenses arranged in two convex cemented achromatic pairs) despite the claims of a number of suppliers including, disappointingly, Sky-Watcher. The range originally had 2.5mm, 3.2mm, 4mm, 5mm, 6mm, 7mm, 8mm and 9mm models. I dismantled the UWA to show the construction. The bottom row of components consists of the housing, a singleton eye lens, a spacer and a thicker black coated cemented doublet lens, (so three lenses in total) and the retaining ring which incorporates the field stop. This main group is identical for all the focal lengths between 2.5mm and 9mm. They have a focal length of about 16.5mm and together are achromatic, but are not corrected for spherical aberration. Without the barlow they give a very blurred image in an F/6 telescope. The spacer is smooth anodised black in all models and while it is out of the proper optical path, its reflection may contribute to the sensitively of these eyepieces to ambient light. The negative Smyth (Barlow) lens in the barrel consists of a cemented pair which not only serves to shorten the focal length, but also corrects the spherical aberration in the main group. There are thus just five lenses in three groups in total, perhaps the minimum for an eyepiece range with constant eye relief and a reasonably wide field of view. The eyepieces under test are the same size and have a similar screw up eye guard. They weigh about 170g (6oz). The eye relief is about 15mm and is enough for me even when wearing spectacles. Despite some suppliers quoting an apparent field of 60° and others 58°, I found no significant difference in true field of view. The lenses are located directly in the aluminium housings. This construction means that lenses can come loose from time to time and the relevant retaining ring needs to be tightened to stop any rattling. I tested these eyepieces in my two refractors (70mm F/6 and 120mm F/7.5) and in my 200mm F/4.5 Newtonian with a coma corrector which extends to focal length by about 10%, to F/5. They all gave a good sharp colour-free image across the field with a clearly defined field stop. I have been unable to distinguish the image sharpness from one to the next, but testing has been limited due to the amount of recent cloud. I have rarely had truly dark skies, but all gave good views of Jupiter, Andromeda, the Great Orion nebula inluding the trapezium and other objects. The eyepieces are nice to use. The eye has to be kept quite precisely in position, otherwise the view is cut off sharply, though newcomers have little problem using them. Any tendency to kidney beaning can be controlled by screwing up the eye cup. I have owned planetary eyepieces of this type for some time and when I have directly compared a planetary against an ortho, the latter has never given a worse image and on occasion has delivered very slightly more contrast on fine detail. However I do not have a 4mm Ortho and was not able see any difference in sharpness, compared with either a 6mm ortho and 1.5x barlow or a 9mm ortho and 2x barlow. There are however issues and two are common to all the models on test. Firstly the large eye lens is pone reflecting any stray light, but this is a minor problem if you can shade it or stick to a dark site. The second problem is the annoying ghost image, seen particularly when viewing planets. This dances in front of your eyes and to me is a serious distraction. When viewing an extended object the ghost is not visible but surely will still be there filling the view and presumably reducing the contrast. I have seen such ghost images in other eyepieces, but it is particularly prominent in these. Differences There are some differences in detail in construction and performance as follows. The TMB ® comes with the same end caps as the HR and UWA eyepieces. The exterior, including barrel is in shiny black. Internally, it has the most effective anti-reflection treatment with a matt screw thread on the inside of the barrel and threading on the barlow lens retention ring. Flare from a bright object just outside the field of view was well suppressed. The TMB SW is entirely finished in an attractive matt black. The eye guard screw is loose and has no grease on it unlike the other three eyepieces tested here and indeed some of my other eyepieces in this range. It comes with different end caps from the other models, which all have the same ones. It has a deep, 0.6mm, shoulder on the barrel unlike the others, which have a similarly, ludicrously deep undercut. I like undercuts but only when they are minimal, perhaps 0.2mm deep, as on my Vixen and Antares Ortho eyepieces.The internal barrel is threaded, but has a bright finish which is not effective in controlling flare. There is also no threading on the barlow retaining ring and indeed this assembly is different from all the other models here. The arrangement is not effective in controlling flare from bright objects just out of view.In the past on one occasion with another eyepieces in the series (9mm), this flare was so bad that it effectively prevented the viewing faint galaxies signposted by Mars. My Antares ortho did not have a problem, so it was an issue with the eyepiece and not the telescope.The eye lens has a coating which shines mainly cyan (red) in colour while the other three eyepieces in this test have a coating which shines mainly magenta (green to blue). see the second photo below. I have three other eyepieces TMB SW eyepieces and one has this cyan coating while two have magenta coatings. Despite the different coating, I was not able to detect any difference in overall view, tendency to ghosting or sensitivity to external light.So far as I can tell, the HR and UWA physically differ only in the eye guard finish. They both have a semi-gloss barrel with a chromed nose, with the deep undercut discussed above. The internal barrel is smooth, but there is threading on the barlow lens retention ring. There is significant flaring and I noted that the previous owner of the HR had taken to the trouble to flock the inside of the barrel. The other difference between the HR and UWA may be something or nothing dependent on your point of view. The HR is clearly branded by Telescope Services, an organisation that surely has the technical expertise to check for faults in the event of problem. In contrast the Sky-Watcher is totally unbranded and the eyepiece appears identical to other unbranded UWA eyepieces. That Sky-Watcher describes the UWA as a Plössl, when it is clearly nothing of the sort, does not fill me with confidence that it knows anything about the eyepiece.Summary These are nice eyepieces to use, but I think that ghosting in all models and the flare in three models mean that they do not meet Tom Back's aim, that they should match the best orthos. They come in a wider range of short focal lengths that any other eyepiece range so are can be useful for filling gaps. There are certainly worse eyepieces available. The best of them is the Astronomics TMB ® in which flare is well controlled unlike in the others. Those interested in such things are assured that some revenue is going to Tom Back's Estate. I shall be retaining this eyepiece. I have real concern over the variability I have seen in the TMB WA, but it may be that familiarity breeds contempt. I also have concerns about the use of the TMB trademark particularly on those focal lengths, 4.5mm and 7.5mm, which have emerged since the death of Tom Back so presumably were not designed by him. Even if this does not concern you, it would not be practicable for most users to fix any flare that may arise from the lack of threading on the barlow assembly. That the shoulder is nicer than the undercut on other models is just about the only plus for this eyepiece. The TS HR is backed by a significant name in astronomy and Markus Ludes worked with Tom Back on a number of projects, but not this eyepiece. If you were to buy one, flocking the barrel would most likely remove flare. The Sky-Watcher Planetary is largely similar to the HR but has no marking to indicate the maker or to differentiate from other apparently identical eyepieces advertised under different names. If you are unconcerned by this and were to buy one, then flocking the barrel would most likely remove flare. Endnote I would welcome comments. I intend to retain the eyepieces test for a couple of months so I can properly answer any queries. If anybody would like to do their own tests, they should send me a PM.
  12. I just received the Celestron NexStar 94004 Rolling Carrying Case I'd ordered for my NexStar 8SE. As the case has only been on the market since February, I went ahead and wrote up a review of it. If you're interested, you can read my review on BestBuy.com (where I bought the case from). Enjoy!
  13. Evening SGL, i recently purchased an Astrotrac TT320X-AG and thought i would give you my thoughts and share my results so far. Any critism and tips or tricks that may help me improve are very welcome. My Astrotrac arrived probably about a month ago now so i have had roughly 2 weeks of Moonless sky to image. This is also my first tracking platform after doing fixed tripod for about a year so its been a great fortnight, as i feel i have squeezed just about all i can out of 30 second exposures! Dont get me wrong, fixed tripod AP is great but i've had an itch to go deeper for quite a while now. The images shown are in the order they were taken. I will put the exposure details below each image. All images are taken with a Canon 1100D (un-modded) and either a Canon EF 50mm 1.8 or a Canon EF 70-300mm 5.6 IS USM. Since my AT arrived just as the Moon was new, i had two weeks to sit and stare at my new piece of gear. I set it up every now and then to get familiar with it. This is a strong point for the AT, i takes 5 minutes to set up and take down. I took advice and also replaced the grub screws in the polar scope with thumb screws to make collimation much easier. A couple of weeks later, my first image, like 90% of everyone here was of course M42. This was a one hour exposure. I was quite happy with my first neb but the image made one thing obvious - the 70-300mm was ****. As you can see, it produces odd star shapes and is just overall, not well suited for AP. Unfortunately i dont have the money or access to anything better right now so this lens will have to do for now. Exposure Details - 2 minute subs, ISO 800, f5.6, calibration frames (darks, bias) also took some 10 second subs for the core. I have also added an hour to M42 but prefer this version for some reason... i think the core looks alot better. My second night imaging i managed to shoot two targets. The first, M45 the Pleiades Star Cluster - one of my favourites. This night taught me that my Polar Scope needed re-collimated more accurately as i couldnt manage 4 minute subs without trailing. I re-collimated the next day. Exposure - 19 3 minute exposures, ISO 800, f5.6, calibration frames (darks, bias) I also got 48mins on Andromeda using the nifty fifty. This lens is awesome, nice round stars. Obviously this image is very heavily cropped. Exposure - 12 4 minute exposures, f5, ISO 800, calibration frames (darks) The next clear night i shot an hour on M33 at 300mm and an hour on Orion at 50mm. All that data was useless. The focus on m33 had slipped and light pollution had creeped in on Orion as it approached the horizon. Gutted. I also had to re-collimate after dropping the Polar Scope on the ground i still need to buy a washer to stop this happening again. A couple days later i set my gear up with a newly bought plug socket power source, so i dont have to buy batteries anymore unless i am shooting in a remote location. I left my camera with the 50mm pointing at Orion. I came back an hour later to find all frames except the 1st covered in a thin layer of cloud... oh well, i had a flick through and found a nice looking shot. The cloud acted as a natural diffusion filter This was a single 3 minute exposure at f4.5 and ISO 1600. Next up was the Horsehead or Barnard 33 if you want to get fancy. This was taken two nights ago under the new Moon after failing again to find PANSTARRS. I framed the whole of Orions Belt just to switch it up a bit from most Horsehead images. Exposure Details - 1 Hour 39 Minutes of 3 minute exposures, f5.6, ISO 800, calibration frames (daks, bias, flats) And finally, my image from last night. Caldwell 49, the Rosette Nebula. Didnt take me long to find it, took me blumming ages to frame it. I was very surprised when this image popped out of DSS. Since i dont have a modded camera, i as not expecting so much to be picked up. Exposure Details - 1 hour 42 minutes of 3 min subs, f5.6, ISO 1600, calibration frames (darks, bias, flats) Overall i think the Astrotrac is an excellent piece of equipment. Yes it is very expensive, including tripod and tripod heads my bill is over £1000. The polar scope lets it down the most but you get used to its flaws and can correct them. I also think portability and ease of use makes up for that. I've had to make some adjustments to my polar scope arm aswell as the polar scope but if you can get it in a sweet spot, you can get some long subs. I can now manage 4 minutes but if i put some more time into fine tuning i could manage longer. I recommend anyone who owns an AT or is thinking of buying one, joins the Astrotrac Yahoo group. There you can find the solution to any problem you may encounter. Next thing i will be doing is selling my 70-300mm and putting the money towards a EF200L, which appears to be an excellent lens for AP. Thanks for taking a look, and remember any tips are welcome. Oh, and sorry about the images being so big. I'm not sure how to make them smaller.
  14. I know the gold standard is, "Making Every Photon Count," http://www.firstlightoptics.com/books/making-every-photon-count-steve-richards.html but has anyone given this other starter a try? "Shooting Stars" by Nik Szymanek I haven't seen any reviews... http://www.astronomynow-store.com/special-editions/shooting-stars-the-ultimate-guide-to-photographing-the-universe Me? I've been subsisting on Allen Hall's "Getting Started" Long Exposure Astrophotography" http://www.allans-stuff.com/leap/
  15. Hi I just posted my Nikon D810A review on my blog http://blogg.astrofotografen.se/2015/05/nikon-d810a-review.html Thought some of you might be interested in reading it. /Göran
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.