PeterC65

I was observing the almost full Moon last night with the BHZ and took the opportunity to check the AFOV that I was getting for a 24mm zoom setting. I found I could only just fit the Moon’s disc into the field of view of the EP and I’d say I was getting an AFOV of about 0.6°. With my Skymax 127 that suggests the BHZ is giving a FOV of 38° for 24mm. The Baader spec says it should be 48° but @Louis D mentioned in this post that it may be less and this review of the BHZ measures the FOV at 42° for 24mm. I haven’t checked the FOV at 8mm but the Baader spec is 68° and that doesn’t seem to be disputed. In a previous post I’d had a discussion about wider AFOV and considered upgrading to 2” eyepieces, but since the AFOV of the Skymax 127 is always going to be limited, and given the cost involved in switching to 2”, I’ve decided to stick with 1.25”. Having made this decision, I looked around for the longest FL EP I could get with a 1.25” barrel and came upon the Celestron Omni Plossl 40mm which I now have. This only has a FOV of 43° but at this FL it gives me the maximum AFOV that I can get with a 1.25” barrel and the Skymax 127 which is about 1.1°. The other reason for going for a 40mm Plossl was to maximise the exit pupil size which people say is helpful when using a UHC filter (since it produces a brighter image). With the Moon so bright I’ve not had a chance to try the UHC filter, or more correctly, I tried it and saw nothing which I’m hoping is down to the brightness of the Moon! It was quite hard to keep the image in view with the 40mm Plossl last night but I assume this was because the exit pupil, at 3.4mm, wasn’t much smaller than my eye pupil in the moonlight? I just needed to stay very still to keep the image fully in view. The Moon looked good through the Celestron EP and easily fitted into its field of view. It also looked good through the BHZ and I found it helpful to be able to adjust the zoom to see just the right amount of cratered arc (zoomed to 12mm seemed about right). The craters in shadow looked amazing by the way!!

According to the Baader website, the Barlow comes with a Type A adapter which gives it a 1.25" male filter thread and a Type B adapter which gives it a T-2 male thread. One of these adapters must always be fitted and to fit the Barlow to the BHZ the Type A adapter should be used. With this adapter fitted, the Barlow screws into the filter thread of the 1.25" nosepiece. Baader say this is how the Barlow is designed to be fitted, even when the BHZ is used with its 2" nosepiece (the 1.25" nosepiece remains in place inside the 2" nosepiece). Neither the 1.25" nosepiece nor the 2" nosepiece turn when the zoom control is turned, so neither does the Barlow. This article, on the Baader website and referring to the Mark III BHZ and Barlow, says that the Type A adapter also has a female thread which fits the male thread on the snout of the BHZ. The snout sits just inside the 1.25" nosepiece and can be exposed by removing the nosepiece. I can't confirm whether there is still a female thread on the Type A adapter as I'm still waiting for delivery of my Barlow but I can confirm that the Mark IV BHZ snout is threaded and does rotate as the zoom control is turned. It sounds like people using the BHZ with the 2" nosepiece may be removing the 1.25" nosepiece and then fitting the Barlow directly to the BHZ snout and in this case the snout and the Barlow will rotate as the zoom control is turned.

Yes, the Barlow can be screwed to the outer thread of lens assembly or to the inner thread of the 1.25" nosepiece (so I've read). Apparently when it's screwed to the nosepiece the magnification of the Barlow is x2.35 instead of x2.25.

I just checked my BHZ Mk4. I don't yet have the Barlow (due in November!) but as I rotate the zoom control the lens assembly at the base of the EP does indeed rotate, but the 1.25" barrel does not. So used in 1.25" mode, with the Barlow screwed to the barrel, the Barlow does not rotate but used in 2" mode, with the Barlow screwed to the lens assembly, the Barlow will rotate. Since the EP is held in place by the barrel in 2" mode the Barlow will be free to rotate anyway and so this isn't a problem. I'm quite relieved as it would have been a pain had the Barlow rotated with the zoom control in 1.25" mode!

Thanks to everyone who has replied with these really useful comments and links. There's plenty here for me to try next time the sky is clear! It seems that within the limits imposed by the human eye (0.5mm to 7mm), a bigger exit pupil means a brighter image which can compensate for the darkening caused by a narrow band filter. If I get the Astronomik UHC Filter then, I'm thinking I should also get a 40mm eyepiece, for the bigger exit pupil rather than for any increase in FoV. I've not had the opportunity to observe the Moon much since the scope arrived and when I did it was very bright. Winding up the magnification on the Moon (and on Jupiter - when the Barlow arrives) sounds like it may reduce the glare and bring out more detail, but @Zermelo suggestion of a Moon filter and @Louis D suggestion of an #80A filter for Jupiter sound like they're worth a try. I can feel another FLO order coming on!

Thank @Stu, your comments are very helpful. I live in a semi-rural location, the countryside of the Forest of Dean, which I think is Bortle 4. We're on the side of a hill, so the view is the south west half of the sky and directly above. The north east half is obscured by the house. Looking south west, there are a few houses in view, several hundred metres away, but no towns or villages. There is light haze in places on the horizon from towns over the other side of the River Severn (10-20 miles away). The closest light source is a single street light 100m from the house and 30” below horizontal. So I'm thinking this is quite a good location other than looking north east. I'm aware of the need to do this but haven't been doing so, but the last couple of nights I've been observing for a couple of hours so I guess the scope will have acclimatised during that time. What effect does not not having the scope acclimatised have? It won't be acclimatised when I carry out the star alignment but perhaps this doesn't matter. I observed Jupiter a few times, including when it was at its highest. I tried to select objects that were relatively high in the sky, including some that were directly overhead. Someone posted camera images of Jupiter in a Facebook astronomy group, taken with the same scope as mine and on the same night. I commented how much more detail could be seen in the camera images and he mentioned that this was the case even with the live unprocessed camera image. He said that bright objects like Jupiter can cause glare which prevents you from seeing details with the naked eye. He can wind down the brightness on his camera to compensate for this. It made me wonder whether a filter that reduced brightness a little might be useful for observing the larger planets (and the Moon)? Maybe the Skyglow filter will help. M13 seems like a good target for me to learn. I'm using Stellarium to locate objects (to control the mount) and to check what I'm supposed to be seeing, both through the finderscope and through the main scope, but the bright laptop screen then blinds me for a while. I did try to look at M13 for 10 minutes or so and that helped. I think perhaps the right thing to do is select a few objects to observe before each session, use Stellarium to draw what they should look like on paper so that I have a reference, then during the session, concentrate on observing just those few objects without going anywhere near a strong light source. How do other people arrange their observing sessions? The focuser on the Skymax 127 is very sensitive I find, particularly when trying to focus on planets. With fainter, 'fluffy' objects I'm finding it even harder to focus on them and have taken to focussing instead on a nearby star. Is this the right thing to do? Part of the upgrade I'm planning (still waiting on a part) is to fit a helical focuser between the diagonal and the eyepiece which I hope will give me finer focus control. I'm aware of what the exit pupil is and how it relates to the size of the eye pupil but I'm not clear about why bigger is better and under what circumstances that is the case. From researching wider FoV eyepieces it seems that lower magnification gives a bigger exit pupil, so is there an advantage in lowering the magnification just to get a bigger exit pupil rather than a wider FoV (because the FoV is limited anyway by a 1.25" barrel size)? From what everyone is saying I should be able to see much more than I am currently so I just need to persevere and learn from the experience of others. Thanks again to everyone who has helped so far!

@SpileWhy do you have to use the 2" sleeve? I've been looking at photographs of the combination trying to work out what goes where. It looks like the Barlow has a 1.25" barrel that replaces the one on the Zoom, and that the Barlow would stick out from the 2" barrel if that is fitted. So I was assuming that you needed to use a 1.25" connection if you fit the Barlow.

Over the last couple of nights I’ve finally had a chance to try the Baader Hyperion Zoom eyepiece. I’ve posted my thoughts here. In summary, it’s better, but only a little bit! From last night’s observing, with the BHZ: Jupiter: With the BHZ set to 8mm I could make out two, maybe three bands of dark cloud across the planet. Saturn: With the BHZ set to 8mm I could see enough shadow to tell that I was looking from underneath the rings, but couldn’t see the Cassini division. M31 & M33: With the BHZ set to 24mm they still look like (slightly better defined) white blobs. There might have been some hint of spiral arms, but I don’t consider that ‘seeing’ them. SAO49528: Stellarium tells me this is a bright star surrounded by bright gas clouds. It looked like there might be a glow around the star, but that could easily have been my eyes. M13: With the BHZ set to 8mm I could see a very dim white blob. As with the galaxies above, there might have been just a hint of the annular star cluster I knew I was looking at. NGC6992: The East Veil Nebula was high in the sky, should be bright enough (7.0), and should fit nicely into the FoV of the BHZ at 24mm, but I could see nothing. I’ve not yet been able to upgrade the diagonal (to a Baader 32mm prism), or fit the Baader Skyglow Filter, as the MAK to SCT adapter didn’t fit! FLO have recently changed their supplier for this part and the new part has the wrong inner thread size. They are sorting it out but it will take another few weeks. And there’s me, thinking that the frustration with astronomy would be waiting for a clear night! I’ve given a lot of thought to widening the FoV as discussed previously. To go beyond the limitations of a 1.25” barrel would be expensive and within that limitation the best I can achieve is 1.09° with a Baader Hyperion 24mm 62° eyepiece (as opposed to the 0.77° that I currently get with the BHZ at 24mm but 48°). But there seems no value in doing even this unless I can see objects that would merit a wider FoV. It may be that the Skyglow Filter will cause such objects to jump out at me! I’ve also read some good things about the Astronomik UHC Filter for observing Nebulae. What do people think can be achieved with filters for visual observing?

I bought my first scope a couple of months ago, a Skymax 127, and posted about my experience setting up and using it here. I’ve since upgraded the standard Sky-Watcher 10mm and 25mm eyepieces that came with the scope to a Badder Hyperion Zoom (BHZ) which I was able to try over the last couple of nights. The BHZ is a well-made hefty piece of kit. It’s quite a lump when perched on the 1.25” barrel of my Sky-Watcher diagonal, held only by a couple of thumb screws! I’ve set the scope height so that I can sit to observe, but at low elevations I need to cant over the diagonal so that the eyepiece is horizontal. To make this easier and to provide more substantial support for the BHZ I’m in the process of upgrading the optical pathway from the visual back. I’m using the BHZ with its 1.25” barrel and with the standard adjustable eyecup. This is quite a big eyecup (55mm in diameter) so it sits tight against my nose and around my eye. Twisting the eyecup adjusts the eye relief (the distance between the lens and the eye) over a range of 10mm. Overall I found it easy to correctly place my eye, either just touching the eyecup or a little distance back from it to avoid scope shake. The BHZ also comes with a smaller rubber eyecup (45mm in diameter) and a winged eyecup. To use these you need to unscrew and remove the standard eyecup and then fit one of the rubber ones over the M43 thread. The smaller rubber eyecup fits better around my eye. It comes with a separate lens cap so you can leave it fitted. The zoom control twist is smooth without being loose, and the focal length clicks can be felt and heard but without affecting the smooth control. In other words, it’s spot on. I compared the BHZ with the Sky-Watcher 10mm and 25mm eyepieces, observing Jupiter and Saturn, the M31 and M33 galaxies, and the M13 star cluster. All of these were clearer with the BHZ, less fuzzy, and I could pick out a little more detail. With the planets I felt there was further room for magnification (I have the BHZ Barlow on order) which I didn’t feel was the case with the Sky-Watcher 10mm eyepiece. But the BHZ didn’t blow me away, it was just a little bit better. The biggest advantage I found was being able to change magnification with just a twist of the eyepiece rather than having to fiddle about in the dark swapping over expensive eyepieces. How do other rate the BHZ?

I’ve been investigating ways to maximise the FOV of the Skymax 127 with the aim of getting a proper look at M31. As @Louis D has mentioned, one way is to upgrade to a 2” optical pathway and then use a 40mm (or longer) EP. I’ve already upgraded the diagonal to a 32mm prism and added a 1.25” helical focuser (to allow fine focussing). I’m still waiting on more parts to put both of these in to action so for now I plan to stick with the 1.25” optical pathway. Another option seems to be the Baader Hyperion Aspheric EP. These are available at 31mm and 36mm although both would be stopped at 30mm if I stick with 1.25”. The EP FOV is 72° and that would give me an overall FOV of 1.44° compared with 0.77° for the Baader Hyperion Zoom at 24mm. That seems like a difference worth having. What do others think of the Baader Hyperion Aspheric EP?

My thanks to @Louis D and @Zermelo. FLO have also confirmed I need the Mak to SCT adapter ring and that is now on order (15-20 days wait unfortunately). From what I've learned, the Skymax 127 sometimes comes with a standard SCT male thread as the visual back and sometimes with a non-standard M45.5 male thread. Unsurprisingly, there is very little kit that will fit this non-standard thread so the best plan seems to be to fit the adapter (https://www.firstlightoptics.com/adapters/lynxastro_makcas-sct_adptr.html) and then you have a standard SCT male thread instead which is much more useful. The SCT male thread measures around 50mm in diameter rather than 45mm and so this is the way to tell what type of visual back you have on your Mak. Eventually I will have all of the kit in hand to upgrade the back end optical pathway of my Skymax 127, and then I'll post on here what improvement that makes. In the meantime the Baader Zoom EP has arrived! It certainly looks very impressive!! I'm looking forward to trying it out next time the sky is clear, albeit with the standard Sky-Watcher diagonal.

@Louis D can you tell me what step-up ring you used? I've just received a Baader SCT to 2" ClickLock which was recommended by my scopes supplier in the UK (First Light Optics), but it doesn't fit. The SCT thread is bigger than the one on the visual back of the scope so I need to know what that thread size is (clearly not SCT).

OK, so the area of sky I can observe depends as much on the FOV of the EP as it does on its focal length. According to Baader their Zoom EP has a 48° FOV at 24mm, and others have said that at 24mm it is similar to a Plossl (the Baader Plossl is 50°) so the difference in FOV may be quite small. Using the figures from Baader, I get 0.77° for the Zoom at 24mm and 1.07° for the (Baader) 32mm Plossl. The Zoom at 8mm gives 0.36°, so a 2.1 : 1 ratio with the Zoom at 24mm, whereas the ratio between the 32mm Plossl and the Zoom at 24mm is only 1.4 : 1. I’m not sure how much of a benefit that would be. When I’ve observed M31 so far, I’ve only been able to see the centre as the galaxy, and then only as a grey blob. It may be that if I could observe the whole of M31 I could then make out its edges and so see it differently but I don’t think that will be possible with the Skymax 127. Interesting that the Skymax 127 is available in the USA with a 2” visual back. I’ve noticed that on larger Mak’s here in the UK. Mine has a 2” SCT thread on the visual back but the aperture diameter within this is only 28mm. Because of this, and because the Baader Zoom is 1.25”, I’ve stuck with a 1.25” optical pathway. Actually I have on order a 2” SCT adapter and 2” nosepiece to fit between the scope and a 32mm diagonal, but that’s mainly to provide mechanical strength and easier slewing of the EP (the adapter is a Baader ClickLock). How did you convert your scope to a 2” visual back? Doing that to mine looks like it would involve major surgery to the scope itself! So I think I’m limited to a maximum 32mm EP which will make it impossible to see the whole of M31 with the Skymax 127.

Thanks for the feedback @DeanCJ. I have seen more each time I've been out observing so I guess it just gets better with time and experience. According to the FOV calculator, a 32mm plossl looks like it would only gives me a little more coverage than the Baader Zoom I have on order (24mm). What do people think? Is it worth having 32mm as well as 24mm? I can see the difference a Startravel 102 would make but I need to get some time in with the Skymax 127 before thinking about another scope! Yes I have just bough a dew shield. It's just a cover, without a heater. I assume these still do the job of preventing dew formation? I considered a heated dew shield but they seem to need additional control kit and would create another power draw on the battery. I doubt I'll be observing for more than an hour when it's cold so hopefully the basic cover will be good enough.

There is very little light pollution in the Forest of Dean which is handy, but I live on the side of a hill which is lined with trees so there is a great view to the south east but not much the other way! I can just see Polaris above the house roof but the scope is on an AZ GOTO mount so doesn't need polar alignment. I'm still waiting for the Baader upgrades to arrive ... In the meantime, I've lowered the tripod so that I can sit at the scope to observe which has made quite a difference, as did better viewing conditions during the last session. Reading the article https://stargazerslounge.com/topic/196278-what-can-i-expect-to-see/ was also very useful and has reset my expectations about what I can expect to see and how much effort and practice will be needed (quite a lot!).

Thanks for the advice. The link to the 'What can I expect to see?' post was very useful. This should be essential reading for anyone considering buying their first telescope! I will try shortening the tripod legs so that I can use the telescope from a sitting position and spend more time at the eyepiece. I think that shorter legs will make the tripod more stable. I'm also considering drilling three small holes in the patio so that the legs can't move and so that I can re-position the tripod accurately each time. I will post again about my experiences with the Baader upgrades once I've had a chance to try them out.

I’ve always liked star gazing and attended the Introduction to Astronomy course at Norman Lockyer Observatory a few years ago (which I’d recommend). Since a holiday has been off the agenda for the last 18 months, we decided to spend the money instead on a telescope and take a proper look at the night sky. Here is what I’ve learned from the first couple of sessions … I chose the Sky-Watcher Skymax 127 SynScan AZ GOTO because: I wanted a descent scope with a good aperture, but also something compact (both the OTA and the mount) as it will get lugged about and stored in the back bedroom. I can find a few stars but don’t know the night sky, so I wanted a mount that would point me in the right direction. I could probably align an EQ mount with Polaris, but two star alignment seemed easier and quicker, meaning more observing and less faffing. Before the scope even arrived I had bought a Celestron 6.1Ah Lithium Powertank. The Skymax 127 comes with a VERY basic battery pack that takes eight AA cells. The mount consumes up to 12W so will flatten AA batteries quickly, and rechargeable AA batteries only have a terminal voltage of 1.2V so cannot provide the 12V needed by the mount to operate properly. The scope really needs to be powered from a Powertank or a mains power supply I think. I chose the Powertank because it’s portable, avoids the trip hazard of mains cabling, and is regulated to maintain the 12V needed by the mount as it discharges. So far a full charge seems to be good for several hours of observing. Surprisingly, there is no power switch on the mount, but I can use the power switch on the Powertank to switch system power rather than just pulling out the power cord! The first night of observing was frustrating! The second time, after properly reading the manual and doing some online research, went much better. Here’s what I learned … Setup Make sure there is enough play in the power cord for the mount to turn through 360° in either direction. Movement of the mount can pull out the power cord if it is tight which then loses all of the setup and alignment data! UPDATE: To really see an object you need to look at it over several minutes so that you become accustomed to the image and your brain begins to pick out the details. In order to do this comfortably, set the tripod height so that you can observe while sitting in a chair. Set the height so that at high elevations, above 70°, you can lean forward in the chair and still comfortably look into the eyepiece. At low elevations, below 30°, I cant over the diagonal so that the eyepiece is near horizontal then observe from the side of the scope. Make sure the mount is exactly horizontal so that movement of the OTA in azimuth through a rotation stays exactly flat. I used a spirit level during daylight to level the tripod top with the mount removed then marked the leg positions on the patio. Power up the mount with it set horizontal (using a spirit level) and pointing true north (using a compass) so that it is approximately aligned from the start. At power up the mount assumes it is orientated at 0° altitude and 360° azimuth. This makes it easier to find alignment objects and it stops the mount from slewing in strange ways (ways that cause the power cord to disconnect!). When finished, Park the mount to its Home Position so that it returns to horizontal and pointing true north for next time. After parking, you can resume next time using the previous alignment data but if the scope has been moved it’s probably best to start again from scratch. The mount has no real time clock (!) so the date (in month / day / year format) and the time must be entered every time it’s powers up. The mount does remember its location so this just needs to be confirmed at power up unless it has changed. I align the mount using the 2-Star Alignment method, choosing two stars that are in the same area of sky where I plan to observe. Only certain stars can be used for alignment, there are around 90 to choose from, and it’s worth deciding which to use before you start observing. I’ve set the Sort order for Alignment Stars to Alphabetic (this is remembered by the mount) rather than by magnitude, as it makes the selected stars easier to find. There are course and fine stages when aligning to each of the two stars. During the course stage the slew rate is automatically set to fast. For the first star slewing has to be done manually, but for the second star the mount will slew automatically to the approximate position of the star (since the mount now has some alignment data). During the fine stage the slew rate is automatically set to slow. You must finalise the alignment of the chosen stars in the centre of the field of view using the Up and Right arrow keys as this compensates for backlash in the mount (when automatically slewing to objects, the mount first slews fast to just left and underneath the chosen object and then approaches the object slewing slowly to the right and upwards). Observation Make sure Tracking is switched on and set to Sidereal for stars and planets and to Lunar for the moon (when using the Object List location function the appropriate tracking mode is set automatically). If an object’s position within the field of view isn’t quite central, it can be tweaked by manually slewing (at a slow slew rate), then the tracking function will keep the object centred. If you think you might return to an object later, it’s worth using Pointing Accuracy Enhancement (PAE) to store tweaks to object positions. PAEs are applied to any objects located within about 5° of the object that was tweaked. I find Show Position useful when manually locating objects to check the current altitude and azimuth positions, and Identify useful to check what objects I might be looking at! One nice surprise is that the SynScan controller that arrived has a USB type B connector in place of the advertised 12V power connector. This enables a wired USB connection to a PC which allows the mount to be controlled by programs such as Stellarium (I’ve tested this and it connects with no effort and works fine). UPDATE: The SynScan controller does a good job of locating objects, but with two lines of display text it can provide only limited information about the objects you observe. Having used the controller to setup and align the scope, I then use Stellarium to control its position and locate the objects I want to observe. Stellarium shows each object in context, provides easy access to magnitude, size and other data, and shows what you might expect to see (more realistically with background DSO images turned off!). I’ve setup the Stellarium Oculars plug-in to show the view through the main scope with different eyepiece and Barlow combinations, and also to show the view through the finderscope. Using the finderscope ocular, I can check what I’m actually seeing in the finderscope to make sure I’m pointing at the right thing, then using the main scope ocular, I can check what I’m meant to be looking for through the scope. So far I’ve been a little underwhelmed by what I’ve been able to observe! I have a cheap and cheerful 45x field scope which gives a good view of the moon and can just about pick out the rings of Saturn and the moons of Jupiter. With the Skymax 127 the moon is much clearer and I can see details of craters when they are in shadow. Saturn and Jupiter look a little better but I can’t see much more detail and at higher magnification (10mm EP) they are a little fuzzy. I managed to find Andromeda (or rather the mount did!) but it looked like piece of cotton wool and didn’t fill the field of view as I had been expecting. When I looked at nebulae I could see the concentration of stars forming them but had no sense of any colour or clouds. Is this par for the course, or am I missing something? So far I’m using the scope as it arrived, out of the box (apart from the Powertank), but I do have on order a few ‘upgrades’ … Baader Hyperion Zoom Eyepiece – to replace the basic eyepieces that come with the telescope (25mm and 10mm) and to provide a range of magnifications. Baader Prism Star-Diagonal – to replace the basic diagonal that comes with the telescope and to provide a stronger mechanical support for the (rather expensive) Zoom eyepiece. Baader Helical Focuser – the focus control on the back of the Skymax 127 seems very sensitive and I see from another post that this helical focuser can fix this. Baader Neodymium Moon and Skyglow Filter – OK, I was getting a little carried away by this point! – where I live is quite rural but this filter seems to improve matters over and above just removing light pollution. When these bits have arrived and I’ve had a chance to try them I will post again with an update.