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Ooh, do I see a new SX camera? Looks like the IMX 571 sensor.

Oh yes. Now that’s awesome. The reflection is 👌 and I love the sky. Definitely a winner and worth the effort of iteration.

https://www.astrobin.com/forum/c/equipment-forums/askar-140apo/chromatic-abberation/ My personal view is that Askar have good mechanics, but cut costs on glass, polish, assembly and QA/QC. Smaller objectives are more tolerant of such an approach than larger objectives. Objective pinching at low temperatures is another area where some of these budget scopes fall flat. Askar also ensure 'A' grade well corrected samples are cherry picked for influencers. Their marketing is hard to fault, and the price/performance ratio is good, assuming you are not in the %age that gets a duffer. Software will deal with minor issues for imaging, and as noted above, visual observers have different priorities to imagers. I'm not anti-Askar. Just pointing out the facts.

If you've racked the eyepiece through the point of best focus on a distant object and only got a blur the optics are probably not collimated i.e the eyepiece isn't aligned with the optical axis of the main mirror as directed by the diagonal. There will be adjustments that can be made on the back of the primary mirror as well as on the diagonal to help you achieve this. To check whether the scope is approx collimated, remove the eyepiece and centre your eye on the drawtube's axis. You should see the reflected image of the spider and diagonal and your eye in the centre of view all reflected back from the diagonal. Very likely it's miles off. David

I was disappointed with previous version. Now with a moonlit, dark blue hour foreground. This enabled me to get much closer to the main subject and show some of the contextual landscape without the castle lights flooding everything. Am much happier. Cheers, Paul. Click for sharper view.

I'll venture a post about Vixen eyepieces, at the risk that it be considered off topic 😃 My personal enabler and Vixen-stuff dealer sold me these four a little while ago… I suspect that they're the ones Roger Vine used in his review of the ED102S: In a relatively short time frame, and with moderate expense the family has grown considerably! While I am putting together a Panoptic/Nagler set for my DSO forays, the Vixens are to be used primarily as my planetary, lunar and multiple star eyepieces in town. Having tried them, I'm pretty sure that I'll be taking them around in my trips as well. I like them a lot: clean, crisp images, super-comfortable to use! Needless to say, they go especially well with my greeny ED102S – but I'm sure they'll make good friends with my other scopes too ;D PS: I was about to skip the 40mm in favour of a 32mm Plössl. When a 40mm showed up, however, my completist side prevailed… good call! In my 920mm-to-2000mm focal lengths it's great to have max 1.25" field and a large exit pupil, plus the eyepiece is wonderful. The other night, along with the ED102S, it gave one of the best views I've had of the lunar full disk!

It's an edge artifact from the Ha layer and I thought I'd fixed it in the latest version! I'll check it out again. Thanks, Wim. Olly Edit: Fixed.

Thanks Geraint - appreciated. It’s hard - I think we’re all wracked with a completely self-induced (and unnecessary!) guilt when it’s clear and we don’t get out. Important to remember it’s meant to be a pleasure!! I enjoyed your printing video - learned some very useful tips to help with my home printing (which hitherto has been very hit and miss!).

Any tips on how I can balance the colors on my images from my astromodified Canon350d? I already tried balancing the colors on the histogram when I edited these photos but I still can't remove the reddish tint (specially for the Omega Centauri).

Thank you Geraint, that's lovely of you to say. It was a bit of guess work your right. Just great to get some aurora this far south. Clear skies Lee

With reflectors the cooling to ambient is to reduce air currents inside the tube disrupting the view , it's not the figure of the mirror that is "off". The relatively warm primary mirror when cooling down creates these currents by forming a thin layer of warm air that rises up the tube causing the shimmering seen at the EP. Cats and Maks suffer the same causing small plumes of warm air around the internal baffle tube. If on the other hand you cool your EPs to ambient you will find them misting up almost immediately when you bring your warm eye up to them so they are better of in a warmer enviroment such as your pocket. It's the same thing as a refractor gathering dew on the objective when warm moist air hits the glass , hence the use of dew shields and dew heaters on the front.

What scope was that in, Louis? If a reflector, was that with a coma corrector and if so which one? Thanks.

You're correct. I'm coming from ioptron however where the power ports are on the back end so don't move, much better design I think.

Good to know! Not quite to thakt level, yet. I migrated from "eye-balling it" to getting a Celestron polar axis finder. and ZWO ASI camera. Because I was setting up for the first time I thought I would go ahead and fine-tune it. A word to the wise -- probably not a bad idea. The polar finders are supposed to be fairly accurate out of the box but mine was probably as far off as it could be. Two set screws (grub screws) were nearly all the way out, and the third was in so deep that it wouldn't budge. I have micro tools so tools weren't an issue. I suggest that when you buy something that has set screws in a ring, look to see if they are all about equal. They should be. If not, return it for having a defect or attempt to fix it at your risk. I happen to have micro screws so I will be able to deal with it. But I'm not happy. Cheers and clear skies ( good luck in the UK)!

Motor is an additional option. It'll be great and hope you enjoy this scope! 👍 Nikolai

How so? The layout seems similar to the AM5, at first glance.

Just in from a short but enjoyable session with the 140 frac. First Light for my Feathertouch on the scope. Wonderful as expected. Seeing seemed not too bad: 268x on the Moon was fine. One Plato craterlet on show, the big central one, in moments of clarity, but no Alpine rille, though it felt as though it should’ve been visible. Not sure what the optimum angle is for that. That remains a Nemesis for me. Epsilon Lyrae a nice split too, first look of the season. Magnus

Very interesting topic, as someone who owns and uses complex eyepieces with large glass in them. I've always tended to keep them just above ambient temperature to avoid misting / dewing when I come to use them (which, when it has occurred, out in the field, has been very annoying). I'm not aware of any performance issues arising from my approach but I suppose I'd have to run a comparison between a cooled eyepiece and one just above ambient to find out. Given that the eyepieces would need to be the same design and focal length to get a meaningful comparison, this might prove tricky to arrange 🙄 Perhaps it's a trade off situation - a small impact for a short time on view quality while the eyepiece cools VS the risk / inconvenience of fogging / misting as the warm eye gets close to the eye lens of a cool eyepiece. I guess the jury is out on this one ?

The annual Lyrid Meteor Shower should already be underway. It is expected to peak during the night of 2024 APR 21-22. Its radiant is in the vicinity of the constellations Lyra and Hercules near the bright star Vega. That is the direction toward which the meteor tails point, but the meteors are equally likely to appear anywhere in your sky. The Lyrids are debris from the long period Comet C/1861 G1 Thatcher. The Lyrids typically present about 5 to 20 meteors per hour for sharp eyed observers, although this has varied considerably with 700 per hour seen in 1803. The show begins after Lyra rises, which is in the early evening for mid-latitude northern hemisphere observers, but much later in the southern hemisphere. It will continue through morning twilight. During the shower’s peak, the waxing gibbous Moon may present some interference in the evening but less so before dawn. Descriptions of the shower or perhaps even lucky photos would be welcome additions to this thread.

They all look like pretend implements looking more closely. Probably just as well not to let them near sharp objects (or laser pointers) 🙄

The tube that is pictured sat on the dust cap of the scope needs to be fitted into the focuser and then the eyepiece goes into that. Apologies if you already know that ! Astro newtonians generally can't focus on things closer than a couple of hundred metres away so your test targets need to be a good way away to enable the scope to reach focus.

I won't lie, the 22mm NT4 is nice and sharp edge to edge compared to the 22mm Redline 70. It was enough different to persuade me to retire the Redline to the B-Team case in favor of the NT4 despite the tighter eye relief and slight SAEP in the NT4.

If you look down the tube from the open end, you should see a magnified image of your face like in a shaving mirror when you have your head at the right distance above the end. It's generally around 6 to 10 inches above the end, IIRC. This is just a quick test to see if the mirror can produce any sort of image.

Hi Dweller, Thinking about this again, from your perspective, perhaps I should have added a bit more of the reason for the question, to add context to it. Maybe if I'd done that, things would have turned out differently, as I certainly had no intention to fall out with anyone, especially given our previously good exchanges. 👍 It's because I'm going to get a 200pds, hence wondered what a 5" frac might add. Mark