Uranium235

Out and about tonight, testing the microfocuser.... which had made things MUCH easier: Shame about the LP in my backyard, it makes (good) luminance work almost impossible, limited to 180s on this. Not that I could go much further anyway without blowing the core too much. 35x180s @ F2

Its all here: Its possible to use your exisiting filter by using a step down ring, which would slow the lens to about F2.5ish - might actually work in a positive way for you as youre stopping down without using the aperture blades (no star spikes)

Cheapo microfocuser I built over the weekend out of what is essentially... junk...lol 1x trpiod collar 1x old 80ED tube ring 1x metal bar (was part of a hinge) 2x M5 bolts

Mosaic building @ F2 Yep... it works I'll do it properly another time... need sleep first!

Yes, if a DSLR is modded, it needs to be re-shimmed - I had to do it with my 1000d. I worked out how thick each shim should be (compared to the originals), and made new ones with feeler guages. Kept the original shims though, safely inside a box marked "do not open!" Any problems could be camera or adaptor related. The less adaptors you use, the better. Mine is just set up with an M48-T2, plus one delrin spacer - roughly ~8.5mm in total. The remaining 35.56mm is taken up by the cam and FW.

Flaming star and buddies. 12x450 (Ha) calibrated data Flats turned out nice, no stupid reflections or illumination off to one side 👍

Have you tried it on another camera? If its consistent, then you know its the lens. You can still shift it on (for daylight phtography) to MPB for a decent-ish sum. I havent tried stopping down the lens yet, it might help with the vignetting. But like the first two I had, I want it running wide open as much as poss. A sammy for 329? i'd be cautious about that... Id ask myself "where is it coming from?", "how will it be treated on its trip?". These lenses do not like being knocked about, i made the mistake of "going cheaper" once, and got a lemon... I knew something was wrong when it took over a month to arrive.

Well... its been a LONG time coming... but I've finally gotten round to testing the new 135 (yes, this is my 4th!). And, unlike the third (which was a bit of a lemon), this one is a keeper. No stopping down on this, I want warp factor 10 please! Just 3x10min to test. But the corners look acceptable, gawd... cant be any worse than the last one...lol. No calibration... just a test stack to see whats what, looks like I got the spacing kinda right with the mark just landing on the "L" (close enough).

Had to get a bit sweaty over this one, lots of star control required. Also, in OIII there is a noticeable halo on the bright star once heavily stretched (nothing can be done about that) but I modelled the backround for that area and subtracted (in Ps) for an overall flatter OIII layer. Tried to retain some decent star colour while I was there. I know theres a fair bit of Ha lurking, but in an effort to keep the overall noise down I'll be slightly more restrained. The image should tolerate some pixel peeping too

Looks consistent with tilt. A fully loaded imaging train acts as a lever under gravity. So any movement in the focuser or imaging train would be exposed. But, I take CCD inspector with a pinch of salt. You would need to take multiple shots of different parts of the sky (but not go past the meridian) to see if the readings are consistent.

DIfficult to see since you havent poseted a full screen shot. But from what I can see it is tilted to one side a little. Even my Star 71 needed its focuser (which was also R&P) tweaking out of the box, there are two bolts on top of the focuser- you may need to nip those up a little (and I mean little). You can check for focuser movenent by racking it out a bit - then basically give it a tug in all directions. If you detect any movement/wobble (no matter how small), then it needs to be tightened up. Still needs to be in focus though to make the correct assessment, before you do any adjustments.

You only need to adiust the flattener if you have introduced a filter into the imaging train or had the camera modified (filter removed). Making the spacing longer will only make it worse, it needs to be shorter. Or in focus. The spacing as detailed by FLO is 11.4mm, however that is the recommended distance, and not every camera/filter combination is the same, so you may need to tweak that by a mm or 2. But, only from a properly (centrally) focused image can you make a proper assessment and decide which way to go (longer or shorter). When focusing, zoom right in to the diffraction pattern... not on the camera screen but using either EOS tools or something like APT. Then, after 45 min or an hour... do it again. (especially during cold weather).

Ok, looking at that image... it is out of focus, but it does display corner characteristics (the distortion is of equal magnitude in all corners) that tell you either: 1) The FF/FR spacing is too long or 2) The optics cannot provide a (perfectly) flat field across APS-C or larger. But, get the image in proper focus first - that might correct a lot of the issues.

Looks like tilt in the imaging train, being as it gets progressively worse from left to right. However, there is a tracking error in there too. 1) Check for saggy or loose connections. 2) Take shorter subs to get an image free from tracking issues (or get guiding) - that will allow you to correctly judge where the tilt is. 3) Inspect the corners of the test sub, make adjustment as required 4) Rinse and repeat until satisfied

Top tip, point it at something big first... like the Moon, you cant miss it...lol. Get it roughly in focus (make a note of its position), then swing round to a planet or star to fine focus.

I can relate to this.... I find it quite soothing to be out, and concetrating on something other than earthly matters.

Cheers...lol... just checkin ive still got the skillz

If you have Ps, the stars could be sorted out using layer masks. Easy... cha cha cha

The sky was just too good to say "no" last night, albeit quite cold! So, I set up for shot at this one and took as much data as possible before it disappeared behind the neighbours house (my southern view is quite restricted, 2.5 hours at most). Decided on the 130pds as its in a good, settled place at the moment and performing (as usual) waaaay beyond its price tag. 14x600s (Ha) 2x2bin (3.4" p/p) 130pds, NEQ6, QSI683 Thanks for looking!

I'll kick it off as usual, just a few from the Askar lens and 130pds

Its that time again! Please use this thread to showcase your best images captured during 2020 (we've all spent a lot of time at home during 2020, so I'm expecting some good stuff). Just one post per member but you can include up to 5 images if you want. The thread is for all imagers, both novices and advanced. Please keep details to a minimum - scope and camera possibly along with a few comments if required. The thread needs to be packed with images so please don't respond to the postings. The previous years showcase thread(s) can be found here: https://stargazerslounge.com/forum/203-imaging-showcase-threads/

Out and about for a couple of hours this evening 14x600 Ha

Bit more effort into this one and should stand up to even the most damanding corner peeper...lol. 8x900s (Ha) 2x2bin x2 panes - fully calibrated, minimal cropping.