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Alan64

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Everything posted by Alan64

  1. I first thought of mounting a Vixen-style clamp, but I didn't suggest it as I thought the other easier, perhaps. You would then need a longer dovetail bar. Actually go with the clamp if possible, as it would be far more versatile. You've got it taken care of, in any event. I need a longer dovetail-bar for this 80mm f/6... ...as it really swings back, with that 2" diagonal, let alone with an eyepiece inserted.
  2. You could add another mounting-plate on top of the AZ3's mounting plate, and forward a bit, then mount the tube-rings onto the secondary mounting-plate, and thereby balance the telescope with whichever new diagonal you choose, including a 2" if you so desire.
  3. The black circle is the secondary mirror, its silhouette or shadow. The misalignment is normal with faster Newtonians, like your 150mm f/5. This is the secondary scene from my 150mm f/5, taken through a collimation-cap, and the scene identical to your own... That misalignment is intentional, and is called the "secondary off-set". The misalignment occurs automatically during a normal collimation procedure, and ensures that all of the light gathered by the primary mirror, that forms the image of an object, reaches your eye, or camera. Here, the secondary off-set explained... http://www.skyandtelescope.com/astronomy-equipment/offsetting-your-secondary-mirror/ From your own image, your Newtoinian looks to be collimated quite well. I see that you have a Cheshire; very good. Do you have a collimation-cap in addition? A collimation-cap allows you to see exactly what's going on inside your telescope... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html Collimation instructions... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf I would just look them over, and for future reference, as I don't see a pressing need to collimate at this time.
  4. I saw that myself. It was Jupiter, and it was pretty close to the Moon; not quite an ideal planetary conjunction, but noticeable.
  5. You're most welcome Guy. I have more planetary eyepieces than I know what to do with, actually. At the time that I got the 30mm, I also got this Vixen NPL 6mm Plossl... If you can tolerate the short eye-relief, the view through that one is like... I've compared it once with my Baader "Genuine" 6mm orthoscopic, on Polaris, and I couldn't tell the difference, but I've yet to compare the two on other objects. Here's the BGO and Vixen side by side... I even made a virtual sketch of the event... The comparison was made with a Celestron C90, a 90mm Maksutov-Cassegrain; a rather dim and very slow telescope. Incidentally, you can motorise your mount, and for automatic hands-free tracking of any object... http://www.rothervalleyoptics.co.uk/skywatcher-ra-economy-drive-for-eq2.html I had an EQ-2 mount once, and I wish I still had it. I gave it and the 80mm f/11 refractor to a relative, and they don't use it. But when I had it, I had a motor similar to that one attached, and observed Venus one morning while it was still dark, and all the way up until noon, and with the Sun shining brightly in the sky. At that point, there in the sunlit sky, Venus appeared a pale sphere sprinkled with fine sand. I have a larger EQ-3, and motorised, but I haven't used it yet. You'd have great fun with the EQ-2 motorised. There's another motor-drive kit available, with a hand controller, too... http://www.rothervalleyoptics.co.uk/skywatcher-ra-motor-drive-for-eq2-with-multi-speed-handset.html With that one, you can substitute an AC adaptor in place of the battery pack, if you observe from home, but always use a surge-protected outlet between the AC power and the motor-drive. There are also other more modern battery-packs that can be used as well; lithium-ion, for example.
  6. You could get by with this EQ5-class mount... http://www.telescope.com/Mounts-Tripods/Equatorial-Mounts-Tripods/Orion-Sirius-EQ-G-Computerized-GoTo-Telescope-Mount/pc/-1/c/2/sc/34/p/116276.uts This larger EQ-6 would be better, but it's a beast of a mount, and for imaging it would be ideal for carrying a 4" refractor and imaging equipment. For imaging, think small telescope and a LARGE mount... http://www.telescope.com/Mounts-Tripods/Equatorial-Mounts-Tripods/Orion-Atlas-EQ-G-Computerized-GoTo-Telescope-Mount/pc/-1/c/2/sc/34/p/116277.uts ...and for best results. When imaging, you don't want to exceed 50% to 60% of the mount's load-bearing capacity. A 4" refractor, camera and other equipment can load a mount down quick. If you'd prefer it in white... https://www.astronomics.com/sky-watcher-eq6-go-to-equatorialmount_p20314.aspx This one is priced higher, and offers an alt-azimuth mode in addition... http://www.telescope.com/Mounts-Tripods/Equatorial-Mounts-Tripods/Orion-Atlas-Pro-AZEQ-G-Computerized-GoTo-Telescope-Mount/pc/-1/c/2/sc/34/p/102340.uts Then, there are Celestron's black-and-orange offerings. They're all made by Synta Optical of China, and therefore a toss-up.
  7. You're welcome Guy. Your Newtonian has a focal-length of 900mm. The 30mm ocular will give you a power of... 900mm ÷ 30mm = 30x That will be about the lowest power possible, and for your brightest and widest view of the night sky; the largest "window" into the night, for observing the larger objects, like the Pleiades and the galaxy in Andromeda during the fall and winter, and for scanning the rich star-fields of the Milky Way during the summer. It will also aid your finderscope in finding smaller objects to observe, then to pop in an eyepiece of shorter focal-length, and higher power, and for a closer look. I took the following snapshot of the Moon one night, with a smaller, faster 100mm f/4 Newtonian, and with the Vixen NPL 30mm... It was warm, and the wind was blowing hard that night, this past January at that, and dark clouds galloped, raced, across the sky, and over the Moon, at times obscuring it... I've used the eyepiece for that, at least, and the event was well worth the ocular's acquisition. Your Newtonian, again, has a 900mm focal-length, so the magnification will be higher, and the view somewhat narrower. I took that first photograph and created a mock-up of how the Moon should appear through the 30mm eyepiece with your telescope... Now, the fun with your telescope will come when you begin to use the higher powers, and a 900mm focal-length is ideal for that. Most objects in the sky are at their most beautiful and engaging when observed at the higher and highest powers. Jupiter and Saturn will be quite the treat, along with many other objects. Globular clusters, nebulae; great stuff, that is. Your Newtonian may already be well collimated, but you'll want to verify that, with the collimation-cap as suggested, and to avoid disappointment when ramping up the power. At the low-to-moderate powers, the collimation is not as critical. With the cap inserted where the eyepiece normally goes, you aim the telescope at a bright, blank, illuminated surface, a wall or other, and position a small camera, or a phone-camera, over the pinhole of the cap, then zoom in to where the secondary scene fills the view, and snap a shot. This a view of the scene of my 150mm f/5 Newtonian... Here it is again, and with its parts described... Circled in green, the main, primary mirror, located at the bottom of the tube Circled in yellow, the secondary mirror, its silhouette or shadow Circled in red, the reflective underside of the collimation-cap, with the center-spot of the primary mirror(or "doughnut") there in the center, and the pinhole of the cap in the center of that. I can tell from that image that the telescope is well collimated. The camera was on the other side of the pinhole, snapping the shot at the time. I suggest using a camera to inspect the scene, as the eye may have difficulty seeing the scene as clearly, especially at that focal-ratio(f/7). Now, your scene will appear similar to that if it's well collimated, but here's a mock-up of the scene of a 114mm f/8, which may be even more similar as to what you should see... Note the much smaller secondary-mirror shadow of the f/8, and compared to that of my f/5. One major advantage with a 130mm f/7 Newtonian is that the secondary mirror is smaller, than that of a faster 130mm f/5 for example, and therefore a smaller obstruction, which should result in somewhat sharper and more contrasty images.
  8. Hello, Do get a variable-polariser of some sort, as they allow 2% up to 40% of the light of an object through to the eye... http://www.rothervalleyoptics.co.uk/antares-variable-polarising-filter-125.html That one is sold out here in the States... http://agenaastro.com/antares-1-25-variable-transmission-polarizing-filter-2081.html ...therefore I expect it to be that good. Such is helpful when viewing Jupiter and Venus, and when they appear as this... When I dimmed Jupiter down one night with my polariser, I suddenly saw colour and details, festoons and whorls within an equatorial band, and instead of all-white as without the polariser. I have the Vixen NPL 30mm, and via the recommendation of one our members here... It has an extendable/retractable eye-cup for comfort, and an enormous field-lens through which to view; most expansive and spacious for a 1.25" Plossl. I don't know whether you have a 130mm f/5 or f/7(longer) Newtonian, but no matter. You'll want to get the collimation spot-on, especially when ramping up the magnification... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf
  9. Hello Rick, and welcome, Is this your kit? https://www.bhphotovideo.com/bnh/controller/home?O=&sku=545212&gclid=CjwKEAjwzKPGBRCS55Oe46q9hCkSJAAMvVuMgEdQkWO1EaZNy2RNdoYvOozXlp1u3ECAvuG2mfQ_uxoC1mHw_wcB&is=REG&ap=y&m=Y&c3api=1876%2C92051677682%2C&Q=&A=details If so, a 2x barlow did not come with your kit. The specs for your kit state that it comes with this... Is that what you're referring to? If so, that's not a 2x barlow, but simply an erect-image 20mm eyepiece that will give you a power of 33x, and a pretty good power for observing large objects, like the Moon. These are barlows, which will double and even triple the power of any eyepiece, and in helping to observe smaller objects up close... If you'd like to have a good barlow, and maybe an eyepiece or two, or three, along with it, Agena Astro offers a very good selection, at great prices and with free shipping on all orders $10 and up... http://agenaastro.com/gso-1-25-2x-achromatic-barlow-lens.html I got my barlows, pictured above, from them, too, along with a few eyepieces. A few inexpensive Plossls would be a great addition to your kit, and for an improved observing experience. Your 5" f/5 Newtonian has a focal-length of 650mm. To find the power that a given eyepiece will offer, simply divide the focal-length of the telescope by the focal-length of the eyepiece. For example, your kit comes with a 10mm eyepiece... 650mm ÷ 10mm = a power of 65x If I had your telescope, I would choose, in addition to the barlow, these Plossls... http://agenaastro.com/gso-32mm-plossl-eyepiece.html (20x), and for your lowest power in helping finding objects to observe. Once you find an object of interest, then you can swap out the 32mm with this 12mm(54x) for a closer look... http://agenaastro.com/gso-12mm-plossl-eyepiece.html You can then 2x-barlow the 12mm for a simulated 6mm(108x), and for an even closer look. You can also 2x-barlow the 32mm for a simulated 16mm(41x). This wide-field 20mm(33x) would be a big improvement over the 20mm erect-image that came with your kit... http://agenaastro.com/gso-20mm-superview-eyepiece.html Understand that the manufacturer, generally, is going to give you a good telescope for the price, but the eyepieces that come with the kit, and other accessories that may also be included, are not so good. They're only intended to get you started, and at the barest minimum; the ground floor. Now, a 5" aperture is theoretically capable of providing a power up to 250x, but realistically, in actual practice and use, the atmosphere and the optical quality of the telescope tend to limit that upper power to about 150x or so. Let's see what would be needed for 150x then... 650mm ÷ 150x = a 4.3 eyepiece, or an 8mm or 9mm combined with a 2x barlow... http://agenaastro.com/gso-9mm-plossl-eyepiece.html (72x), and when 2x-barlowed for a simulated 4.5mm: (144x) That's one 2x barlow, three Plossls, and for six different powers... ...20x, 41x, 54x, 72x, 108x, and 144x. It's like having six eyepieces for the price of four. Barlows are very useful in that regard, and in extending a useful set of eyepieces. Do not choose eyepiece sets offered by Celestron or Meade. It's best to build up a set of eyepieces instead, to get your money's worth, and eyepieces of better quality. With the wide-field 20mm in addition, you'd have a wider view at 33x, and 65x when the 20mm is combined with the barlow. Your telescope is a Newtonian, and therefore may or will need to be collimated upon its arrival after its long and bumpy ride from China, and occasionally as you use it in future... http://www.schlatter.org/Dad/Astronomy/collimate.htm http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf Within those collimation instructions, you will read of a tool called a "collimation cap"... http://agenaastro.com/rigel-systems-aline-telescope-alignment-eyepiece.html The collimation-cap allows you to see the entire optical system inside your telescope, as shown here with the scene from my 6" f/5 Newtonian... ...and then to make adjustments as needed, and for best image quality. The higher the power, the more precise the collimation(alignment) will need to be for sharp images at those higher powers. In order to use the cap, the main, primary mirror will need to be center-spotted. Look down the opening of your telescope and check to see if your main mirror is already center-spotted, like this... ...and please let us know, then we'll go from there.
  10. You're very welcome, and thank you. Wide-field oculars, other than offering expansive views of larger objects, first became popular with the advent of the manual "Dobsonians"; larger Newtonians on Dobson alt-azimuths. I'm sure you've seen them. For the most part, with the Dobsonians, the wider views simply allow observing an object for that much longer before it races out of sight, and then to bump and nudge the telescope to view it again, over and over until one moves on to another object and repeats the process. With a motorised mount however, one no longer becomes dependent on wide-field oculars for that purpose, as the object now remains still there in the center of the eyepiece. At that point, it then becomes a matter of just how much sky background you would like to see surrounding an object; to frame it. Some like a lot of "air" surrounding an object; whilst others prefer to focus on just the object, and without being distracted by other objects in the field-of-view. Per exit-pupils, at f/5, the lowest power for the 8" can be had with this relatively-economical 2" 38mm 70°... http://agenaastro.com/agena-38mm-super-wide-angle-swa-eyepiece.html ...and for a low power of 26x; almost binocular-like. With that, you'd have a sporting chance of seeing the galaxy in Andromeda in the fall and winter, but you'd have to pan the telescope along the galaxy's length to view it in its entirety, as it's quite large. The eyepiece would also allow you to relaxingly take in a wide view of the congested star-fields of the Milky Way on a lazy summer evening. For practically everything else, the 1.25" format will do nicely. This economical 20mm 68° would offer a power of 50x, and for a closer look, but not too close, if you spot something interesting with the 38mm and would like to zoom in a bit... http://agenaastro.com/gso-20mm-superview-eyepiece.html You can then 2x-barlow that 20mm, and for a simulated 10mm(100x), for a closer look still... http://agenaastro.com/antares-1-25-2x-barlow-lens-twist-lock-adapter-t-thread-ub2stl.html A 3x barlow would convert the 20mm into a 6.7mm(149x)... http://www.telescope.com/catalog/product.jsp?productId=8704&gclid=Cj0KEQiAuonGBRCaotXoycysvIMBEiQAcxV0nIAXccASK-NmxYURKPL_pkDyxz_GSsLtSzoSDLBFsBIaAvoS8P8HAQ There is also this 3x within this listing, and an Antares like the 2x listed above... http://www.scopestuff.com/ss_ebt2.htm To find the power offered by any given eyepiece, or eyepiece-and-barlow combination result, simply divide the telescope's focal-length by the focal-length of the eyepiece being considered... 1000mm ÷ ?mm = ???x You also have the option of skipping barlows and getting dedicated eyepieces of short and very-short focal lengths. For examples... http://agenaastro.com/eyepieces/1-25-eyepieces/shopby/5mm_and_under-5_1mm_10mm/bst_uwa_planetary-agena_dual_ed.html Take this 3.2mm for example... http://agenaastro.com/agena-1-25-dual-ed-eyepiece-3-2mm.html 1000mm ÷ 3.2mm = 313x! An 8" aperture is certainly capable of 313x, but only if the collimation is spot on and the atmosphere is cooperative. Florida is well known for very good seeing conditions, so I've read. Jupiter and Saturn will feature prominently as this year wears on, and to see them well the Newtonian must be collimated properly, as the magnification will need ramping upwards, to, say, 150x and greater, and for a lovely view; that is, both planets will blow you away with an 8" aperture. Then there are globular clusters, tighter and open star-clusters, and nebulae that can benefit from the use of oculars of moderate focal-lengths, for example... http://agenaastro.com/agena-1-25-dual-ed-eyepiece-15mm.html (67x) http://agenaastro.com/agena-1-25-dual-ed-eyepiece-12mm.html (83x) Those particular eyepieces offer 20mm of eye-relief, and are very good for those who must wear prescription eyeglasses when observing. Do you wear eyeglasses, and would you need to wear them whilst observing? Eye-relief is simply the distance one needs to hold their eye away from the eyepiece, and in order to see the full field-of-view, and comfortably... If you know that you do not have to wear eyeglasses when observing, like myself, then you can make good use of most any eyepiece on the market. The eye-relief is usually listed within its specs within its listing. If not, you can research any given eyepiece online for the information. Plossls are the current minimum provided with better telescope kits, and are also sold individually... http://agenaastro.com/eyepieces/1-25-eyepieces/shopby/gso_plossl/gso.html But Plossls below 10mm have tight eye-relief, and where you would need to hold your eye where it almost touches the eye-lens of the eyepiece, and to see the full view. Such is true with this 6mm Plossl of mine... ...and the views through same are nothing short of mesmerising. I have the 1.25" 30mm as well... ...and with an enormous eye-lens through which to view. That one would provide a power of 33x with an 8" f/5. The Vixen NPL Plossls, as that 6mm, may be a worthwhile step up in quality over the GSO Plossls, but I have no GSO Plossls to compare to my Vixens... http://agenaastro.com/eyepieces/1-25-eyepieces/shopby/vixen_npl/vixen_optics.html In so far as negotiating eye-relief, that's where barlows can help, too. You can 2x-barlow a 12mm Plossl, for an effective 6mm, yet retain the greater eye-relief of the 12mm. This is my 4mm orthoscopic. It has a tiny eye-lens through which to look, and tight eye-relief; ouch... I can observe with it, but for improved comfort I often choose to 2.8x-barlow this 12mm instead, and for an effective 4.3mm, and for 174x with my 6" f/5... I've seen glory with that combination. Incidentally, many objects are at their most beautiful, most engaging, at the higher and highest powers. Then there's this current 4mm(250x, with an 8" f/5)... http://agenaastro.com/bst-1-25-uwa-planetary-eyepiece-4mm.html Note how similar that one appears to my combination above. That's because it contains built-in barlowing elements, and all in one piece. If an eyepiece of short focal-length has a large eye-lens and a longish body, it will most likely contain a barlow, built in. For the lower powers, there's generally a wider spacing between the focal-lengths within a set of eyepieces, and for the higher powers a closer spacing... ...and, in my case, with a few barlows to complement. However, I usually do not barlow an eyepiece longer than a 12mm myself. I also have a 16mm that I like to use on occasion. Then there's always the minimalist approach, and with one or two eyepieces and a barlow, or three eyepieces without a barlow. Such is dependent upon the observer's preference. If you'd like more experience and time in determining what you would like in a carefully thought-out set, you can choose the 2x barlow suggested, for now, along with this... http://agenaastro.com/celestron-8-24mm-zoom-eyepiece.html It would serve as a teaching tool, and in determining at which powers at you would like to observe best, then to select dedicated eyepieces at those focal-lengths and powers, and of better quality as funds and time permits. The zoom ocular would not provide particularly wide views, but I have read that at the highest selection, 8mm, that that would offer a somewhat generous 60° actual field-of-view. As you can see, you have a myriad of options to explore.
  11. I had gotten this 6" f/5 Newtonian back in the spring of 2013... I didn't really start using it until 2015, two years later. I soon tired of lugging that particle-board mount around and transferred the Newtonian itself to a tripod-type alt-azimuth... Afterwards, I had a blast with it, and in reaching magnifications up to 174x, at least, and with excellent results. I can realise even higher powers once I start using it on my equatorial, but that's going to wait until I add a new focusser to the 6" f/5. To date, this amounts to nothing more than a prop... ...but to be a practical reality in future. From what I know of the performance of my 6" f/5, you will very much enjoy an 8" f/5 for visual even more. Incidentally, back in 2003, I custom-ordered an 8" f/5 Newtonian, and manufactured by Parks Optical of California, said company now defunct. They were in business from the 1950s to the mid-2000s. They didn't offer their 8" Newtonians in an f/5, ever, only f/4 and f/6, but they graciously agreed to craft my own... I have yet to observe with it, however, as it needs a mount. I had purchased it to cure any future bouts of so-called "aperture fever", and by simply having it in my possession, even though I've never observed with it, it does its job as an elixir of sorts for said fever quite well. Have a look at what Parks once offered, and now lost in time... http://www.parksoptical.com/index2.php?cPath=21&cat=Telescopes http://www.scopecity.com/brands.cfm?SearchBrandID=177&bn=Parks Optical&TopCategoryID=1&SubCategoryID=57&DisplayType=1&ManufacturerCategoryID=57 Incidentally, the Parks site, and that of its retail store, Scope City, are up still only for reference. Orders cannot be placed on either, thankfully, as one might lose their money in so doing. But I got my cookie from the jar. If you purchased just the AVX, and a 6" f/5 Newtonian separately, you would lose a little visually, but the AVX could handle the 6" f/5 for imaging a good bit more. Incidentally, have you ever collimated a Newtonian? Such is essential for imaging, and for the higher and highest of magnifications during visual use. Since you're considering a Newtonian, you might as well get a head start on the process... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf Do not consider eyepiece sets, from either Celestron or Meade. It's best to buy eyepieces individually, and build up a set over time; over the weeks, months, and years even. Eyepieces are just that, and for the eye, and their selection is somewhat akin to getting a prescription for eyeglasses. Agena Astro has a wide selection of eyepieces, at varying price points, and with free shipping on all orders of $10 and up... http://agenaastro.com/ A 6" f/5 or 8" f/5 parabolic mirror is going to hunger for better-quality eyepieces, and in order to deliver pleasing views to the observer, but not ones that would break the bank. I'll go into that in a bit more detail later, if you're interested, as it's now time for bed.
  12. In that you have a 200mm Newtonian, and on a Dobson alt-azimuth, a variable-polariser can come in awfully handy when viewing Jupiter and Venus... ...afocal shots via my 150mm Newtonian, and just as one would see during a live view through an eyepiece. Note the flares radiating outward from the planets, and the intense brightness. Even after increasing the magnification on Jupiter, it was still all-white and the flaring evident still. Then, I added the variable-polariser to the eyepiece, and the result was extraordinary. I dimmed Jupiter down to the point where the flaring disappeared entirely, and the brightness to where I could begin to see the planet's colours; the whorls and festoons within its equatorial bands in addition. It was though I was watching a NASA broadcast on a mid-1960s colour television set. Afterwards, I then picked my lower jaw up off the ground. http://www.rothervalleyoptics.co.uk/antares-variable-polarising-filter-125.html You simply screw it on to the bottom of an eyepiece or barlow, then twist the bottom half of the filter to adjust... Even though you dim the object down as though you're using a smaller telescope, you will still benefit from the full resolution, the detail, of a 200mm aperture.
  13. It is understandable that beginners tend to place visual and imaging in the same astronomical basket. In reality, the two exercises are in two different baskets, in two different galaxies, light-millennia apart. Imaging is the far more expensive exercise of the two. With visual, you sit there at the telescope, pop in an ocular, and look at things, in real time, in the moment. You not only see with your eye, but with your mind as well, and the mind soars. With imaging, a camera takes the place of one's eye, but the camera must keep its "eye-lid" open without blinking, and all the while with the telescope and camera being held very rigidly in position as it tracks an object, impervious to the winds blowing it must be, whilst collecting the light of an object over varying periods of time, and over and over. Then you take all of those images and stack them into one image with a computer programme or programmes. I would suggest one of these kits for visual initially... https://www.bhphotovideo.com/bnh/controller/home?O=&sku=917581&gclid=CjwKEAiA0fnFBRC6g8rgmICvrw0SJADx1_zA3zd7LfgUF9rxGPpDwdbwiA8ViFeLFSfGwrPigvBDIxoC6QTw_wcB&Q=&ap=y&c3api=1876%2C92051677802%2C&is=REG&A=details https://www.bhphotovideo.com/bnh/controller/home?O=&sku=917562&gclid=CjwKEAiA0fnFBRC6g8rgmICvrw0SJADx1_zA4Ff_uU-nP0m2ci9zFgFpIBcvpkbSbFv3UkEjM20VVhoCrcvw_wcB&is=REG&ap=y&m=Y&c3api=1876%2C92051677802%2C&Q=&A=details Then, for deep-sky imaging, get on the wait-list for this... https://www.astronomics.com/astro-tech-at72ed-72mm-refractor-telescope-black_p18263.aspx But get these in the meantime... https://www.amazon.com/Deep-sky-Imaging-Primer-Charles-Bracken/dp/148180491X https://www.amazon.com/Astrophotography-Manual-Practical-Scientific-Approach/dp/113877684X Cameras, their sensors, are far more sensitive to light than the human eye, therefore cameras do not not need large telescopes in order to "see". I would recommend taking baby-steps when approaching said discipline.
  14. Charcoal-lighter fluid dissolves grease almost instantly, and adhesives, especially that left behind after the removal of duct-tape. It behaves similarly to mineral spirits, and is harmless to plastics. It is petroleum-based, and therefore flammable, so care should be used in that regard. I've found that I've needed nothing much other, really, within my tinkerdom. Best of all, you get a lot within a single bottle, and it's cheap to boot.
  15. I've used charcoal-lighter fluid, the kind for grilling outdoors, to clean old grease off and out. It works wonders in that regard, and is safe for all materials and surfaces. You might be surprised as to just how many of those little bottles of this brand-name cleaner and that are actually and essentially the same thing. I use old toothbrushes and coarse artists' brushes with the fluid to clean, gear-teeth for example; and paper towels, rags and cotton-swabs soaked with the fluid for other areas. You can also use 91% rubbing-alcohol in addition for certain areas. After cleaning with the fluid, wipe away the excess and allow to evaporate. Despite the fluid's relatively low-odor, always use any cleaning fluid in a well-ventilated area. Never use acetone, especially on plastic. There are only certain instances in which to use acetone. For instance, if you modify a plastic part, and rough and jagged edges are left, acetone will smooth them out. You then "paint" the acetone over the plastic. For example, when I flocked my 150mm f/5 Newtonian all the way up to the outer edge of the aperture, the dust-cap would no longer fit. As it was, and before the flocking, the cap would snap shut, like it was never to be removed... It now glides in and out, butter-smooth, and will not fall out. Such is a rare instance in which acetone is useful with astronomical equipment.
  16. Yes, Dave and I have mind-melded once again. I lost my small tube of Super Lube. I think it fell into the trashcan whilst I wasn't looking or paying attention. I then got the much larger cartridge... I think it'll be a lot harder to lose that one. Yes, Super Lube is great! I've used it on my CG-4 equatorial; and this microscope that had gone through a fire, and during its reassembly after I had taken it completely apart and cleaned it... It doesn't require much when applying. I use a larger hog-hair artists' brush myself.
  17. With its metal focusser, and a boon towards considerable ease in collimating, along with its 150mm aperture, that particular model is one of the best of its type.
  18. Back in the olden days here in the States, the best beginners' kits were a choice between two telescopes: a 76mm f/16 refractor, or a 150mm f/8 Newtonian. The 76mm refractors appeared as this back then... http://www.cloudynights.com/uploads/gallery/category_352/gallery_224509_352_162329.jpg ...whilst the Newtonians appeared as this... https://www.rit.edu/cos/observatory/images/tel/tt01.jpg ...that is, if you were a lucky youth. Both were quite long, and for mostly lunar and planetary observations, and as though it was taboo to look beyond the solar system at night. They were made in Japan, and were quite costly, unlike today. Now you can choose, penny-wise, between at least a 102mm refractor or a 200mm Newtonian, and now made in China. A 150mm f/5 Newtonian is bright and powerful for its size, yet compact enough for a quick jaunt out into the garden, or on a trip... Magnifications range from a low and wide-field 19x, to 250x and beyond with the aid of either a 2x or 3x barlow; most versatile for observing practically everything in the night sky. Your skies may be darker than my own, and I have a blast with mine beneath my skies. Occasionally, I take an afocal photograph, by holding a small camera up to the eyepiece and snapping a shot; steady now, and on the fly... Mind you, those aren't even short exposures, let alone long ones. They appear exactly as you would see them through the eyepiece during a live observing session, and as I saw them just before taking the shots. The Newtonian design is somewhat testy, however, in that it requires collimation of the two mirrors in relation to the focusser, initially, then to tweak it on occasion. The higher the powers, the more critical or precise the collimation(alignment) needs to be. The most beautiful images are seen at the higher and highest powers, and then to have seen what few people have ever seen before. The Trapezium star-cluster within Orion is nothing short of mesmerising at 188x. I would have a look at these instructions before deciding on one... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf Collimation tools... https://www.firstlightoptics.com/other-collimation-tools/rigel-aline-collimation-cap.html https://www.firstlightoptics.com/other-collimation-tools/premium-cheshire-collimating-eyepiece.html The effort to learn and master collimation is well worth it, and most rewarding, for the images produced by a classical Newtonian are 100% free of false colour when viewing brighter objects; sharp and clean. Once collimation of a Newtonian is mastered, no other telescope design of this Earth will remain a mystery. I can't stress the importance of collimation enough to those first starting out, and because invariably the urge to ramp up the power is inevitable, and should be without disappointment. As it is, the atmosphere conspires against us all from the beginning, therefore there is absolutely no need to compound the situation further with a sort-of-collimated Newtonian. I and others will be more than happy to assist you in the owning and operation of a Newtonian. I, for one, have many pictures...
  19. An extension lined with an absorptive material, like thick felt or other, always to be flat-black in colour and sheen, can help keep dew at bay... https://stargazerslounge.com/topic/98110-diy-dew-shields/ Now, the one in that thread doesn't appear to be lined, but lining it with self-adhesive sheets of black felt would help in addition. I made one for a 90mm Maksutov... The one in the background was my first attempt, and with brown felt, as I couldn't see the reddish tone there in the store at the time. I then went back to the store and returned the unused pack of brown and got two of the black. I did try the brown one, for kicks, and indeed it did seem to add some colouration whilst observing. I also used aluminised, or chromed, bubble-wrap for the frame; perhaps not the ideal material, but I did find the notion online... http://www.dewbuster.com/dewshield-sct.html When I make more of them for some of my other telescopes I may choose something else for the frame. Some jacket their telescopes entirely... https://stargazerslounge.com/uploads/monthly_03_2012/post-15675-133877742386.jpg https://stargazerslounge.com/uploads/monthly_03_2012/post-31003-133877742378_thumb.jpg Those are passive solutions. You can incorporate electrified heating-strips if dew proves to be especially problematic. As for the eyepieces, I would keep them stored in a warm, dry case when not in use. If they're dewing up whilst inserted into the focusser, then you may need to resort to an electrified solution.
  20. However, you might like one of these better... https://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-az4-mount.html https://www.firstlightoptics.com/reflectors/skywatcher-130p-ds-az4-alt-az-mount.html
  21. The 130mm f/5 tabletop kits are quite popular. Here's an enormous thread from the States regarding the 5" f/5 AWB OneSky(Celestron), which is the same exact telescope, both manufactured by Synta of China... http://www.cloudynights.com/topic/463109-onesky-newtonian-astronomers-without-borders/ A 130mm f/5 Newtonian can be quite the little performer at a dark site. My first telescope was a 60mm f/11 refractor, so you'll have me beaten.
  22. For the OP, Raazor, in addition... It appears that Costco is the only vendor of the Inspire 90mm kit. The specs... http://www.cochaser.com/blog/wp-content/uploads/2016/12/Costco-1089293-Celestron-Inspire-90AZ-Telescope-spec1.jpg ...a 90mm f/10 achromat, with a 900mm focal-length, and for minimal false colour when viewing brighter objects at night; excellent, and a very good buy if it was had for US$150. Synta Optical, who produces these kits, equips them with a rather curious ball-shaped diagonal. The diagonal supplied is a 90° Amici, or erect-image, prism. Such is really only suitable for use during daytime/terrestrial observations, and when the overall optical quality is not as important. For astronomical use, at night, a star-diagonal is preferred and recommended, and for the ideal observing experience... http://agenaastro.com/celestron-1-25-telescope-star-diagonal.html ...and with free shipping. I have a 45° and a 90° Amici-prism diagonal...and that same Celestron 90° prism star-diagonal... Note the generous aperture of the 90° prism star-diagonal, at left. That of the one included with the Costco kits is narrow and constrictive; like observing through a drinking straw, for the lack of a better analogy, and with its aperture being very similar to that of the 45° Amici-prism, at right. This individual traded the same, bundled, ball-shaped, 90° Amici-prism diagonal, and for the Celestron 90° prism star-diagonal... http://www.cloudynights.com/topic/543510-grab-n-go-scope-various-questions/?p=7366176 Simply read on for their improved observing experience... http://www.cloudynights.com/topic/543510-grab-n-go-scope-various-questions/?p=7368124 Observing at night is all about larger apertures and wide fields-of-view. Open up the light-path of those refractors, and start really enjoying what the telescope has to offer. Why, the word "star" alone informs the user as to which type to use at night... I have a couple of eyepieces like the ones that come with said kits, which came with one of my own... The larger 17mm isn't bad, but the 10mm is not very good. The design of these eyepieces, Kellners, or modified-achromats(MA), are a bit dated and uninspiring. The manufacturers of these entry-level kits tend to provide good telescopes; but the eyepieces and accessories, not so much. Only the barest minimum is provided. Plossls are regarded as the minimum standard here in modern times, and are economically-priced... http://agenaastro.com/eyepieces/1-25-eyepieces/shopby/gso.html Out of that GSO line-up, and for a useful set with which to observe most any object, I would suggest... 32mm Plossl(28x) 20mm SuperView(45x) 12mm Plossl(75x) 9mm Plossl(100x) ...and a 2x barlow to combine with the 12mm, and for simulated 6mm(150x)... http://agenaastro.com/gso-1-25-2x-achromatic-barlow-lens.html The 9mm can also be barlowed, and for a simulated 4.5mm(200x), and for the Moon especially which tends to take even higher powers quite well. Plossls shorter than 10mm to 9mm have tight eye-relief, the shorter the tighter, and where you would almost have to touch the eye to the eyepiece to see the full view. This Vixen 6mm Plossl of my own has very tight eye-relief... If prescription eyeglasses are needed whilst observing, then eyepieces with much greater eye-relief will be required. The eye-relief measurement of an eyepiece for sale online is usually included within the specifications of its listing, with 15mm to 20mm being chosen, generally. The Vixen line of Plossls are very nice, yet still reasonable in cost... http://agenaastro.com/eyepieces/1-25-eyepieces/shopby/vixen_npl/vixen_optics.html I have the Vixen 30mm as well, and with an adjustable eye-cup for ease in eye-positioning, and an enormous lens through which to observe... The nice thing about purchasing eyepieces, barlows, diagonals, et al for an existing telescope is that they can be used with other telescopes that may be acquired in future. Such are like luggage, and for life. Telescopes may come and go, as one upgrades or sells off, but a set eyepieces and accessories can have a much greater longevity, if chosen sensibly. Eyepieces are one with the telescope, for you can't use one without the other. You can even use a telescope without a diagonal, but a viewing-lens of some sort, whether an eyepiece or camera, is not optional.
  23. Iain, that's a very if not extremely good afocal snap with a phone-camera. Feel free to ramp the power up to 200x and beyond when observing the Moon. I took this shot at almost 200x with my 150mm f/5... Congratulations on the new kit!
  24. I got to looking around. It could be that the corrector-lens is as this within yours, and this from the larger G8-N... If so, you may need to remove the lens in order to collimate the secondary mirror, focusser and primary mirror as one, then reinstall the lens.
  25. In that event, I would get a collimation-cap, and perhaps even a Cheshire, and among the first three items within this listing... https://www.firstlightoptics.com/other-collimation-tools.html Once you remove the corrector-lens, you can insert the cap where an eyepiece goes, and view the entire scene of the optical system inside, and consisting of the primary and secondary mirrors only... ...and then to collimate it in the manner of a traditional Newtonian. A Cheshire is useful in centering the secondary mirror directly under the focusser, and in ensuring that the eye and eyepiece are aimed directly at the center of the primary mirror, once the mirror is center-spotted... This iillustrates a common location of the lens, and attached to the bottom of the focusser's drawtube... I'd clean the lens, too, whilst at it, in addition to the secondary mirror as well. This is a Celestron PowerSeeker 127mm, the largest of Celestron's Jones-Bird reflectors currently, and with the focusser disassembled and the corrector-lens appearing as a separate component at far right within the fourth image down... http://www.cloudynights.com/topic/502410-celestron-powerseeker-127eq-rebuild/?p=6624249 The primary mirror and its cell is easily removed from the optical-tube. Simply mark its position in relation to the tube, remove the screws, and as you've already done, then carefully work it out. Simply click on the images to enlarge... The primary mirror assembly exploded... When reinstalling the mirror, you don't want to snug let alone tighten down the clips. Use a slip of paper or a business card for a proper clearance between the surface of the mirror and its clips... Else, the mirror will be pinched by the clips, and you would see that effect in the images themselves. The clips are only for keeping the mirror from falling out of the cell, not in battening it down to where it's immovable. Center-spotting the primary is absolutely necessary for collimating with the tools, and isn't that difficult... https://stargazerslounge.com/topic/286250-collimation-secondary-doesnt-seem-centered/?do=findComment&comment=3138680 Collimation instructions, which can be helpful with the Jones-Bird as well... http://www.forumskylive.it/Public/data/serastrof/201281510358_Astro Babys Guide to Collimation.pdf http://www.schlatter.org/Dad/Astronomy/collimate.htm I would take photographs and make some notes during the cleaning, center-spotting and collimating, throughout. The plate that covers and seals the back of the primary cell should be left off permanently. The primary mirror needs air-circulation, in order to acclimate to the outdoor conditions, and for the ability to conduct high-powered observations that much more quickly... The plate only serves to smother the mirror. The secondary mirror assembly is the most finicky portion of the optical system. It moves in most every direction imaginable, the motions akin to that of a gyroscope, in tilting and rotating, but not as fast... https://www.youtube.com/watch?v=DsOU0WEc6OU But the secondary mirror must come to rest in only one position, directly under the focusser, and circular in shape... To make adjusting the secondary and primary mirrors more easily, take one of the small set-screws from each assembly to a local hardware that sells screws and what-not loose in bins, size them up, metric most likely, and replace them with longer socket-cap bolts, then to adjust with the hand rather than with tiny tools... You can also replace the larger screws of the primary cell, and replace the rubber grommets with sturdier springs instead which will help hold the collimation better. The C150-HD f/6.6 catadioptric is larger than what's currently marketed, and should be a bit easier to work on as a result. I know that I wouldn't mind having one to explore.
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