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Hi, I got my son a Skywatcher 200 Flextube Dobsonian telescope as an upgrade to his 3D-printed Hadley telescope. He was excited and we went out to try it out in the backyard even if conditions were not optimal (neither the moon nor any planets were up, it was slightly cloudy, and there is some street lights and general light pollution), but we have previously been able to see lots of stuff in his old Hadley. We started by collimating the telescope with a laser collimator. Researching a bit, I have since found out that the laser collimator needs to be collimated itself, which it certainly wasn't. We didn't have the right hex-tool to collimate the secondary mirror, and it was almost centered anyway, so we only adjusted the primary mirror a bit. We used the 25mm ocular, found a group of clear stars, located them with the finder scope (the finder scope wasn't aligned with the primary scope), but was completely unable to locate them or anything in the primary scope. No matter how much we searched and tried focusing, we did not manage to get anything but a uniform grey view inside the primary scope. Once or twice we saw a bright shape shaped like the UFO, but I suspect that was just a nearby streetlight reflecting on something. The plan is to get out in daylight soon, get the finder scope aligned, and retry the collimation, but even with all those done badly, I would have expected us to be able to see something, even if washed out and out of focus. So I suspect we have done something else wrong. Do anyone have any hints on where to start troubleshooting? Cheers, Rasmus.

I have not studied any of the AI noise reduction methods but your proposal, at race value, makes sense.  All image processing loses information.  However, it allows us to modify an image so we can visually see the "features " in the image we want to bring out. At a practical level it would be easy to do both (AI then bin or bin then AI) and compare the result. Regards Andrew 

The time when China was copying only simple aspherics and simple Konig designs like the 'red lines' appears to be over. The one I got is a new item (as far as I know) in the AngelEyes line of eyepieces. I prefer AngelEyes as it seems to me they are a brand that know what they are doing, without all the pomp and marketing of SVBony. One thing is always guaranteed with them, you get what you pay for. A 30$ eyepiece is better than a 12$ Plossl.. simple.. and their 87$ is far better than the 30$ eyepiece. This was also the reason I bought it. My thinking was that if a 'budget' brand like Angel Eyes is suddenly selling an 83$ eyepiece, it is not going to be bad and it will have a lot of glass. I was right. Keep in mind, this is with a 20% EU Tax.. You may get it cheaper from AliExpress in another country. Before I go to the eyepiece, let's get a couple of things on budget China pieces settled down. I will admit, I've always been a fan of budget friendly eyepieces sourced from China and so far I have not been disappointed, even after spending a full night testing out Morpheus, Explore Scientific, APMs in much better telescopes than mine. Reason is simple, my 8" f/6 is very forgiving and not that bright (making any errors not as easy to see). I think every discussion about an eyepiece should start with the focal ratio and type of telescope it was tested with, otherwise it is a waste of time. I've noticed there is a huge, and I mean huge difference on how these eyepieces perform depending on the focal ratio of the telescope. The 40mm 2" Kellner is nice to use in my 8" .. in the 12" f/5 it just completely breaks apart 50% out of the field. Something similar, though not as radical happens with the 'red lines' as well. The whole reason I went in the beginning for the 8" f/6 instead of the 10" f/4.7 was so that I can focus on actual observing and learning instead of spending a ton of money on eyepieces. Also I had no idea what eyepiece to get exactly, why and what focal length. This relatively safe strategy worked really well with f/6 and pretty much all the stuff I got was used at some point. Although I do have two friends, not one but two, who use the 'red lines' and Kellners in their f/4.7. They told me they have simply gotten used to it and are not in a rush to upgrade. Interesting. No coma correction as well. But then once I got to a 12" f/5 everything pretty much fell apart. One the focal ratio is faster and second the telescope is brighter.. so there are more aberrations and there are easier to see. This necessitated that  I get some better eyepieces. I knew this going into the 12" , maybe I was hoping it wouldn't be so bad, but it was , so I went shopping. I am glad my first scope was not a 10" f/4.7. I would've been lost without the experience I gained with the 8" and my budget stuff. First choice was simple, the SkyRover 30mm UFF (APM 30 UFF clone). A lot has been said about this one already, I've read a lot about it over the last year or two and it was first on my list. I will say only this, it is a total spoiler. Comparing any other eyepiece to this one makes the other eyepiece look lousy. With this being said, I have not been able to compare the Angel Eyes 14mm to anything else premium in my telescope. I am also using it without a Coma Corrector in a 12" f/5, so this is something to count with. I don't know how much of the stuff around the edges is Coma and how much other aberrations. I wish I could compare it to something a lot better and more expensive. I am comparing it directly with the SVBony 'red lines' 15mm that go for about 30$ and my SVBony Zoom 7-21mm. So we are talking a price difference of about 63$.  The eyepiece line has a 7mm , 14mm and 22mm. I don't feel the need for a 22m as the 30mm UFF is just amazing and covers anything low power I want. The 7mm on the other hand is just too much high power. I am not a big planetary guy and for DSOs this seems a bit too much. Maybe in the future, we shall see. But the 14mm was the clear winner I wanted because that is what I use 50% of the time. An exit pupil of about 2.5-3.0. In the 12" f/5 this is an exit pupil of 2.8mm. Very bright, sharp, lots of resolution, nice and comfortable.  The 'red lines' and the 2" Kellners I've used with my 8", for all their shortcomings in an f/5, have had a very nice, comfortable eye relief and have spoiled me in this regard.  This was the reason I went with this one instead of their other premiums, a 16mm 82 degree for 85$ but a 10-12mm eye relief instead of 19mm. I am very curious to see how these perform but 16mm is a tiny bit too low for me, I wish they had a 12mm in that range. Also that 82 degree without a CC is not going to go well. It has a very comfortable eye relief of 19mm. The image is super crisp, bright and sharp. On par with a simple Plossl. In comparison my favorite 15mm 'red line' was 'softer' even directly in the center, nevermind the edges. I also feel the color of the stars is different. The correction around the edges is pretty good, except for the last 5 degrees or so. I believe the majority of what is happening there is Coma. It does look like Coma but without a coma corrector I can't say for sure. The AFOV is more like 66-67 degrees. I am comparing it directly with the 30mm UFF which they say has 70 degrees. So in this regard either Angel Eyes is lying about their 70 degrees , or the 30mm UFF has 73 degrees instead of 70. Anyway , I wish it was the same as the 30mm UFF but 66-67 is very nice nonetheless, especially with the vast majority of the field being very nice and sharp.  The field is flat to my eyes as far as I can tell. Focusing on a star anywhere in the field focuses the whole field. So the claim of Flat Field is true. To be honest I was not as bothered by the other errors in my other eyepieces as the lack of focus across the field. I'd rather live with shredded stars than blurry stars. Some observations of the Moon at low horizon didn't show any obvious kidney beaning. The 'red lines' are pretty touchy in this area, especially the 6,9mm. The field stop is sharp and easily seen. I am not a fan of vignetted field stops like the SuperView 30mm or my 'red lines' 6mm and 9mm. I love the clear crisp black line.  Several discussions on Barlows made me do some testing for an entire hour. I took this eyepiece and tried it with a 1.5x Barlow screwed at the bottom or a 2x Barlow. I compared it with my fixed 'red lines' and there was no contest whatsoever. The image was brighter, sharper, more whiter stars, simply better in each and every way. Would a fixed eyepiece from the same line 7mm be better than a Barlowed 2x 14mm? Don't know. I was using a simple Celestron Omni 2x 2 element barlow. I would be curious to compare but I don't think the results would be worth the extra 83$ for the 7mm. I just don't see how it would be radically better. So the math is simple here, instead of buying a 6mm , 9mm and 15mm 'red line' it is a LOT better to get their 14mm and an Omni 2x Barlow, basically for the same price. I am not regretting my 'red lines' as that was a valuable learning experience and they were pretty good in my f/6, but the choice here is simple. At the time I bought them this 14mm didn't even exist or at least I didn't see it back then. The eyepiece is pretty heavy for a 1.25" and for an AngelEyes eyepiece , comes at 300 grams and sits very nicely in the focuser with the rest of the body being at 2". This is the only downside when Barlowing 2x, it feels a bit weird in the focuser. But this is just a cosmetic issue. Under closer inspection of their design, this appears to be a Panoptic Design with a 'barlow like' lens at the bottom before the focal plane. The 14mm has 6 elements in 4 groups. The 7mm and 22mm have 8 elements in 5 groups. I am very curious to know why the 7mm and 22mm require more elements and more groups? What makes these mid-powers so special and not requiring as much as glass? I noticed this also in the 'red lines' that the 15mm is the smallest and simplest. The bottom line is that this is some of the best 83$ I have invested into an eyepiece so far, maybe second best to the 179$ of the SkyRover 30mm, that thing is just amazing even for that money, maybe worth easily double that. Some impressions. M13 looked amazing , M92 as well and at a Bortle 4 location it showed really nice dust lines (finally) in M51 as it was right above at 90 degrees. It was so good and outperformed my other stuff (even with a Barlow) by so much that I am selling everything and keeping only the SVBony Zoom 7-21mm , this 14mm one and the 30mm UFF + my Barlow 2x,3x. Minimalism at its best. Over time I may go for some planetary eyepiece, like their 4mm 82 degree looks interesting. Need to get some field experience with my Zoom on what is the best high power focal length for my new 12". Once I figure out where I spend most of my time, I can get a fixed one.      

It would seem that threshold has been reached 😂 Much more manageable than the large CC’s by the looks, what’s it like to mount up? Not sure if a handle would be nice (if possible to add)?

Unless the big box above is red...then you do clouds