michael.h.f.wilkinson

I typically level the tripod when the tripod is fully loaded (or level it, load it, and then check and adjust levelling again). I have the Vixen GP and GP-DX wooden tripods, and the aluminium EQ3-2 tripod. The former are pretty solid, but even with those I see some degree of flexure. Levelling the tripod when loaded works well for me, even on the rather more flimsy EQ3-2 tripod.

+1 for the Nagler 22T4. It is one of my favourites, and is in my view the best of the Type 4 Naglers, with the 17mm a close second. I will not upgrade to an Ethos of any kind because the eye relief of 15 mm is just too tight. If you don't wear glasses, the Ethos should be better (but costs more). I once compared my Nagler 12T4 with an Ethos 13 mm, but didn't get along with the eye relief on the latter. Conditions weren't good enough to give a meaningful comparison of image quality at the time

Much depends on target and conditions. The views of DSOs through even a really good refractor (e.g. TEC-140) vs a 20" Dobson (Olly's Sir Isaac) under identical (very good) conditions are simply incomparable. M101 and M51 were absolutely stunning in the 20", and even my 8" SCT slightly outperformed the TEC-140 on those diffuse targets, where sheer light grasp is needed, and you are working at a comparatively low magnification, so the exact PSF of the optics is relatively unimportant. The Saturn Nebula was another outstanding target in the 20" Dob. That scope gathered enough light to show the vivid blue-green colour. Likewise globulars really improve with aperture. In a 4" frac I see the brighter stars, but the first time I spotted it through my C8 I was just gobsmacked at the myriad stars visible in M13 (the 20" Dob was in another league). For really wide-field targets, like M31, a smaller scope with short focal length is sometimes better. Some of the best views of M31 and M33 I have had were with the APM 80mm F/6 triplet, and 31T5 or 22T4 Naglers. Likewise for the North America Nebula. The 6" F/5 Schmidt-Newton with the 31T5 (a.k.a. the Panzerfaust) is also absolutely wonderful on those targets, definitely beating the views of (almost invariably slower) fracs of similar focal length. For planets, the situation is a bit subtler, as sky conditions limit what extra aperture can offer. I still prefer the views through my C8 to those through smaller scopes, but it only really gets an edge under good conditions. A C11, or big dob (or both) are definitely on my wish list

As an extra experiment, I combined the stacks obtained with the 6" F/5 Schmidt-Newton (762 mm focal length) with 6660 seconds worth of data from the 80 mm F/6 (480mm focal length) obtained earlier. APP has no problem stacking two previous stacks, and in the combined data some of the outer shell structure is coming out. As ever, it needs more data, but I will give it another go with the Meade SN6

Tried tweaking curves in my recent Dumbbell Nebula shot. Again, I feel it depends on the monitor I use which is better. This is the original, which looks fine on my laptop, but a bit washed out on some other monitors This is the new version, which looks fine on my other main monitor, but perhaps overstretched on my laptop

Yesterday it was surprisingly clear, so I trotted out the Meade SN-6 6" F/5 Schmidt-Newton, and tried it out on the Vixen Great Polaris mount (normally I put it on the GP-DX) to see how that would work. The SN-6 is just 300 g heavier than the C8 OTA, and a little bit longer, but with a much shorter focal length. The mount handled it well, and I gathered a load of images using the ASI183MC and Optolong L-eNhance filter. I didn't get guiging working yet, and my polar align wasn't good enough to go beyond 15s subs, but I gathered 484 of them on M27, or 2 h 1 min worth. Stacking in APP took a while (5 hours or so), but I am rather pleased at my first M27 at this focal length. Star colours are a bit weird, so I think I will try to get some regular RGB data and combine them. I also gathered a quick 151 15s subs on M57, but that really requires more focal length Still, progress is being made

Could be. If so darks should reduce the issue

Code we developed might be used reducing those data, for faint, extended object detection in particular. Actually, 3.2 Gpixel images aren't the biggest we have processed. Our current record stands at 165 Gpixel remote sensing data, and we hope to tackle a 1.5 terapixel image some time soon

The Meade SN6 and ASI183MC on my Vixen Great Polaris mount in action, grabbing data on M27

The idea of the contest is to mix astrophotography and art, so it is certainly a valid entry. However, I am not a particular fan of this shot. I feel there were far better ones (including Alexandra's)

Very nice result. Haven't had decent skies here yet, alas

Welcome to SGL from up north in the Netherlands.

I tend to go for sealed lead acid batteries, of the deep-cycle variety. I have a 20 Ah and a 105 Ah variety (the latter was on offer for a ridiculously low price). I then make my own cables, usually 1.0 mm^2, which is plenty for most mounts. This should work better than having to up 5V to 12V

Nice capture! They can outshine entire galaxies, as in the case of SN2020rcq in UGC 6930, which peaked at mag 11.8 whereas the galaxy is listed alternatively as mag 12.1 or mag 13

I have the William Optics 7.5-22.5 mm Zoom II, with between 18.0 and 19.5 mm, and it is very comfortable to use with glasses. I find 15mm is too short, 16mm is usable, anything from 17-22mm is fine. Longer can be a pain too

Unexpectedly, the skies cleared today, so I drove off to my observing spot north of town, on the dike by Aduarderzijl. My aim was to have a go at imaging Jupiter and Saturn, and trying to hunt down supernova SN2020rcq in UGC 6930. I set up the C8 on the GP mount, and had a look at the gas giants, first at 93x with the Nagler 22T4, then at 145x with the Delos 14 mm. Jupiter was decidedly mushy in either, with a combination of boiling seeing and atmospheric dispersion affecting the view. Saturn was considerably better, perhaps due to the slightly higher altitude, or the fact that Jupiter was above some distant houses, and Saturn was over a waterway. The Cassini division was only visible fitfully. Mars was visible lowin the east, but the view was awful. I then turned to hunting the supernova. This was an easy star hop from Phad, and with the big 14x70 finder I got the right spot quickly. I first tried the Nagler 31T5, but upped the magnification by inserting the 22T4 once more. I could not spot the galaxy (unsurprising, in the moonlight), but there was definitely a stellar object in the exact spot indicated in the finder charts I printed. That's supernova number 15 bagged! After a little war dance on the dike, I turned back to the gas giants, but Jupiter was still mushy, Saturn a bit better. I then turned to Mars, which had risen considerably higher, and now showed a lot of detail. I then turned to M57, and it was a gorgeous sight, despite moonlight. After a quick trundle across the moon (never ideal at full moon) I called it a night.

I can heartily recommend my Helios LightQuest 16x80 binoculars. I use them a lot, despite having a cracking good APM 80mm F/6 triplet. The Helios LightQuest 16x80 is about the same weight as the Helios Apollo 15x70s I had before, and clearly shows more detail and fainter objects than the Apollos. They are also easier to steady than the 20x80 model. Getting out a grab and go scope or grabbing binoculars just isn't the same thing. I do the latter much more than the former.

I gather some people bought the SN6 on the LXD55 mount in order to get the mount cheaply, and planning to use a different scope on it. In reality, the OTA was clearly the best part of the set. The idea of putting an SN10 on an LXD55 mount is crazy. I wouldn't even consider putting it on my GP-DX mount, which is a lot more solid than the LXD55 from what I have heard

I think those are Celestron branded BA-1 binoculars. I had a lot of fun with a similar pair, but they are effectively 15x63 (still a very useful observing tool). I replaced them by Helios Apollo 15x70 bins and they are clearly a step up, but also a lot more expensive. I have since got a pair of Helios LightQuest 16x80 bins, and they are even better, showing more detail, and coming in at the same weight as the Apollo 15x70 bins. The BA-1 types are certainly worth the price asked, but they can be knocked out of collimation quite easily.

Here are my two Cats on their Vixen mounts. At the back you can see the trusty old Celestron C8 on its Great Polaris mount, both getting on for 25 years old (but not yet showing the EQ-5 Synscan upgrade), and the more recent Meade SN6 Schmidt-Newton on the Vixen GP-DX mount I bought from @Stu, complete with the SkySensor 2000 PC controller. Both superb mounts.

Observing chair and big 14x70 RACI finder (both home made). Straight-through finders are literally a pain in the neck, and an observing chair means you can sit at the right height, wherever the scope happens to be pointing.

It is currently reported as magnitude 11.8, so it is still brightening

Wise move to go for the heavier of the two mounts. I have used a Celestron C8 on a Vixen Great Polaris (GP) mount. The EQ5 is a clone of the GP, and the GP handles the C8 well for visual and planetary imaging. However, I wouldn't want to put an 8" Newtonian on it, especially for imaging, as it is much heavier and longer (more torque) than the C8 OTA. For DSO imaging I generally use the GP mount with my APM 80mm F/6 triplet, and might give the Meade SN6 (6" F/5 Schmidt-Newton) a go on it.

Glad you were able to spot it

Here are some finder charts I made with the AAVSO VSP tool For my RACI finder scope, 3.0 deg FOV, mag limit 11.0, north up, east left orientation For the Schmidt Newtonian, Same FOV, mag limit 13, south up, east right orientation: For the C8, 1.0 deg FOV, mag limit 14, north up, east right orientation: