Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.



  • Content Count

  • Joined

  • Last visited

Everything posted by Space_Plane

  1. Certainly a strange one! From memory it was occurring no matter the exposure, 10, 30 or 60 seconds, and I wasn't guiding either. I see some minor diffraction spikes on the bigger stars from being stopped down a bit and oddly they don't seem obviously triangular. I'm out of ideas anyway, no clear nights for a while for any more tests, and I don't assume I can fix pinched optics in a lens Thanks again for your input.
  2. Many thanks @michael8554, I've attached one of the preview subs from that session, auto-stretched straight from the ASIair. Its a bit lower resolution but its particularly noticeable in certain areas. I can upload some of the .fit files later if you think that might help? Thanks Chris
  3. Thanks Roland, yes, it was bought new only a few days ago, 85mm F/1.4 AS IF UMC (if any of that helps!) Manual Focus. I was quite disappointed lol, I'm hoping its just something I'm doing wrong, but I've used multiple other (and much heavier) lenses with exactly the same setup and haven't had any issues like this
  4. Hi, Recently got a new Samyang 85mm 1.4, and as luck would have it, had a clear night to experiment with it on my asi178, attached via geoptik adapter. Did a quick smash and grab on andromeda after taking dozens of different exposures testing focus and how far to step the lens down. I'm relatively confident my PA & tracking etc weren't "too" bad. The attached png of the stack is 20x1min at f2.8, with nothing more than a crop at the edges and 1 set of levels to make the issue more obvious. Best focus I could get was just shy of infinity. All the stars are triangles! Any ideas? Chris
  5. Thanks for that vlaiv, was an interesting read (google translate helped me out a bit ) Certainly gives me lots to consider, and typically the lens has increased in price in a "sale" lol, so I have time yet to continue my research!
  6. Many thanks for the input everyone. I was never 100% sure vlaiv if a smaller sensor kindof, sits in the middle / "best" part of a lens and only the bigger sensors receive the worst of the aberrations at the edges, or whether the lens acts like a funnel and all sensors get all aberrations regardless of size. Fascinating Do you remember where you saw some test shots? I quite like the idea of it for the price, but the combination results in 5.82"/ px. Wasn't sure how badly that would affect images, maybe things would be a bit, blocky? Thanks again!
  7. Hi all, I have recently been looking at the Samyang 85mm and considering using it with an ASI 178. Has anybody got any experience with it? I know the 135mm is rather famous and well regarded, unfortunately also twice the price Thought this lens might be worth a try for the slightly wider fov and hilarious f ratio, and hoped maybe the tiny chip on the 178 might "skip" the worst of any potential edge of field aberrations? (if i understand that correctly). Cheers Chris
  8. I am quite intrigued by this, I always just assumed it had to be as close to infinity / spacing as possible, 'virtual' infinity is totally new to me ? Its similar lenses I have at present, all vintage takumars, 55, 135 & 200. When I was out briefly a few days ago it was the 135 I tested, and you're right, it looked about as best focus it was going to get between 1/2 and 2/3 of the travel. It still looked quite soft though, whether that's just how it is, or whether it would be sharper at more accurate spacing / infinity mark I don't know. Hopefully find out next clear night! Thanks
  9. Wow Vlaiv, that's an incredible amount of helpful and useful info, thanks for taking the time to go into so much detail! I'm really rather looking forward to getting to try all these things out, especially the .ser files and gain/exposure settings. Sounds like it'll make a lot of difference. Just need some clear nights lol ? Thanks again
  10. Hi Rich, That isn't something i've come across before, i'm fascinated. I've only used these lenses with a DSLR before, and it was really picky about focus / infinity. The slightest movement knocked it off. Due in part to larger sensor then i presume? I managed to get out the other day and experiment a bit, and with the adapters I have, was about 41.5 out of 44mm. The lens would vaguely focus about half way around the focus ring, but it wasn't great. I wasn't expecting ~2.5mm to make such a difference to the focus. Look forward to getting different extensions and trying to get it sorted a bit better. Cheers
  11. Thank you both for your comments and suggestions, its greatly appreciated! I must have slid the gain and exposure sliders up...and down....and up lol over and over, it mostly looked very blown out on screen, so just took a guess ? I'll try higher gain and lower exposure as you suggest, and certainly more frames, sounds good. Is there a benefit to .ser? I haven't tried it before. The initial images I took had loads of squares all over them at different zoom levels, which led me to debayering & pipp after some research. I'll look into bayer drizzle instead. Lots to experiment with! Thanks again!
  12. Hi all, Just a quick post after spending an hour the other night experimenting with my new zwo178mc-cool. I'm new to cmos cameras, new to pipp and debayering, new to autostakkert etc lol The following is 5 x 10ms images, 0 gain, 25 offset, roughly (and badly) focused by eye on an unbalanced 72ED-R / AZ-GTI I've a lot to learn but it was a fun first outing. Tips & criticism welcome ? Enjoy! Thanks Chris
  13. Hi everyone, Thanks very much for your info & associated discussion, and Rich for your offer. I'll have to read more into your suggestion Olly, i've never tried it. I wonder if i can make it work on my star adventurer ? I haven't quite decided what i'll do just yet, have to think about my spacing a little. The spec of the geoptik says 19mm, the backfocus of the 178 is 17.5mm and the potential adapter above is 5.5mm, for a total of 42 of I believe the required 44mm? Not sure how to best deal with 2mm! I'll be using vintage lenses for now, but I think the m42 -> canon adapter I have will work ok here, seems to reach infinity fairly well on my canon dslr. Supposedly clear spells here over the weekend, might get a chance to start experimenting ? Thanks again Chris
  14. Hi all, I'm just starting down the path of imaging with a cooled zwo 178mc, and have hit a few bumps! ? I purchased a geoptik canon-ccd adapter as I'm planning to use it with short focal lenses for now. Any ideas how best to align the sensor..."squarely" to the adapter, for easier framing etc? Maybe its not as big an issue as I assume? I've seen the following T2 rotation adapter which I think I'd just about have the space for. Anyone ever used them or know if they work ok etc? Any advice & suggestions welcome ?
  15. Hi Peter, I have used the hoya red enhancer with a older takumar 135mm lens & dslr. I live in a very light polluted area, where a 30 second exposure is basically orange. It certainly allowed me to increase my exposure time, and the colour balance was much better, a nicer colder, more toward blue. I would say it introduced a slightly red tinge, but certainly easier to compensate for in photoshop than orange mush. I was pleased with it for what I paid, but it was much less than £90 (smaller filter), your mileage may vary! My dslr is not modified either, i couldn't be sure how that would effect images with this filter. Hope this helps Chris
  16. Hi all, The synscan pro (and maybe non pro) app on android has just been updated with the following changes / fixes. Hopefully it'll help some of the issues described! ? Cheers • Use a new format to save alignment data. • Fixed problem where app caused third party app using compass/tilt to malfunction • Updated AZ tracking algorithm • On Android: can save diagnostic log in Settings > Diagnostics menu • Improved connection error reporting • Fixed a crash involving hibernate • Allow setting SynScan Wi-Fi's 2.4G channel • Sync encoder: made more accurate and allow performing on mount without aux encoder.
  17. Hi Tony, greatly appreciate your explanation. I was always starting (best i could anyway) north and level, and the mount would slew as hard as it could, just...not even close to where it should be going. I hadn't considered manually pointing toward the first alignment star, I look forward to giving it a go asap. Part of me expects it to just wildly slew off somewhere else in the sky haha, but hopefully not! Thanks again
  18. Hi, Many thanks, I've been following that thread with great interest, incase the same thing happens to me! For clarity I'm basically unclear if I'm even completing the alignment / goto correctly. What is the best process to follow? Any time I try to align (assuming I always start from north & level) the scope points nowhere near the target. I have no idea yet if tracking after a goto is successful (having never...gone to, lol). Cheers
  19. Hi all, Recently got my first goto mount, the AZ GTI, and haven't had much success with the goto function. The mount seems to track fine if I manually move it and "point and track", e.g. the Moon stayed central in the eyepiece for a long time last night, but no matter what alignment method I attempt (1 star, north level etc) once it completes, it is nowhere near the target! Instructions with the mount are a bit....thin, and I've read as much as I can find. When aligning, with any method, does it always have to start, telescope level on the left hand side, mount pointing north? (like north level). Sorry for what is probably a daft question, ? the answer maybe applies to all goto mounts / alignment. For info: being used with Synscan Pro app on android, with a balanced 72 ED-R scope & fully charged external powerpack. Thanks!
  20. Hi @ZBOYD, Thanks very much indeed for the detailed info & photos, it's exceptionally helpful! I'll certainly be looking into this asap. Clear skies!
  21. Hi @ZBOYD, mind if I ask what tube rings you're using with the 72 EDR? I have the same scope, and have never been 100% sure what ones would work! Would love to get my hands on the AZ GTi when its back in stock, and these would certainly help. Cheers!
  22. Hi, I too have mine on an EQ5 tripod with one of the Berlebach adapters, and as Charl says above, it certainly is stable and easy to lift and move about with one hand. The only minor annoyance I have with it is that when it is all tightened up (on mine anyway), the SA doesn't line up with any of the legs to point North, it sits in between two. Ultimately this doesn't overly matter and theres many ways around it, just might be handy in certain circumstances
  23. Hi, Similar to Nicos above, i was wondering what the internal diameter of the rings were, and if there is any chance they might become available separately? As skywatcher seem to sell every other size of tube rings Cheers!
  24. Hi, thanks for the info! My cam isn't modded, and I was shooting m45 just as a test, so all very bright I suppose, and only 1 stop down at f4. I'll have to try a few more variations when I get the skies and see, I'll maybe make a post in imaging somewhere if it persists. I was thinking it might be a focus thing, I just blindly put it at infinity, assumed it would be fine Thanks again!
  25. Hi, Very nice images, I particularly like the range of star colours. I took my first photos with a takumar 135 last night on my SA, and all the stars have a reddish fringe/halo! Do you use any filters with yours?
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.