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Everything posted by Uranium235

  1. Thanks Peter, I reckon I could push it up another notch if I add three more hours in Ha, then a bit of OIII for some cannistra colour. Ive not used an OIII filter with the Askar yet, so it will be interesting to see how it turns out.
  2. The humble 80ED, still punching well above its price tag all these years later
  3. Looks good, but to kill that noise - I would personally opt for subs which are much longer than 300s. You are using a CCD, so your exposure time is only limited by the brightess of your target, or the local LP - neither of which should come into play in narrowband. So ramp it up to 900s and replace some of the data captured under "less than ideal" conditions, if you keep bad data in the mix it can sometimes bring down the end result... a case of quality over quantity perhaps, but ideally its quality and quantity. It will take a while since you may need to manually inspect all of your subs and toss "bad" ones into a separate folder. If you can push it further than 900s, do it. Higher risks yes, but the rewards are worth it (but 900s is a good benchmark to start off with).
  4. Great capture Steve The QSI683 Im using also throws the occasional wobbler, usually in the form of the dreaded windows 7 "ding dong" to tell me the camera has disconnected itself. The only way to bring it back online is to disconnect/reconnect both the power and USB cables, then wait for the two beeps before reconnecting via maxim.
  5. Yep, that little bit exta FL does buy you more detail. Possibly more if you shoot it to the point of being noise free (maybe 6 hours), then drizzle, process, and resample downwards.
  6. Ive been sitting on this data since last weekend, havent been feeling so great this week (baaad insomnia) which kinda took the wind out of my sails (unable to concentrate/think/operate normally). But today hasnt been so bad, so my clarity of thought has improved enough for me to process it properly with flats/bias. Thankfully, after a bit of tinkering and very patient focusing - Ive got this working at f4 with corners that are more acceptable (to me).... hurrah! 14x900 (Astrodon Ha) Askar ACL200, NEQ6, QSI683 Thanks for looking!
  7. Hmmm... imaging at sub arc-second has shown up a guiding issue with the 130 tonight. Might be time to find a different place to mount the finderguider (perhaps in the middle of the dual saddle, between the scopes).
  8. yay.... a clear slot! A bit mushy, but its better than nowt i suppose
  9. this is why my filters are kept fanatically clean the only motes I cant get to are on the sensor window itself (which is usually hidden behind a shutter).
  10. How clean are your filters? Because theoretically, you can use any flat from another filter (try L) to correct the red channel (as long as all your filters were clean when you took the images) - try it
  11. I got the gear out, fiddled for a while (getting both scopes pointing at the same thing)... and.... the sky turns to mush... fantastic... not! I'll leave it out for a bit, in case the band of cloud passes and leaves a clear spot - but I wont run it past midnight if its not going to clear up properly.
  12. Thats a depressing amount of satellite trails =/ and its only going to get worse
  13. Belt n' braces approach is best for CMOS ive found (well the ASI178 anyway). Darks, Dark flats, Bias, Flats I even match the setpoint cooling for all calibration frames (yes, for flats as well so you get a correct ADU measurement as hot pixels skew the readings)
  14. You have to realise that LDN targets are usually quite difficult and require a lot of exposure and/or very fast optics. But, I can see the dark stuff in your image - you just need to calibrate and flatten the background correctly in order for you to process it properly. Remember... youre looking for black, in the blackness of space, so you need to have plenty of exposure so the dust has something to "stand out" against. LBN are the same, sometimes theyre Ha, but other times its just faint dust illuminated by nearby stars (L) - witch head nebula is an example. And it can be all but impossible from your average back garden location (even with a CCD).
  15. Looks pretty good, Ive pixel peeped it and towards the top of the frame is where its still not quite right - might just need a bit more spacing on the CC (depending on which you have). But remember, you are on the very edge of what is possible with this telesope now... the last 5% is always the hardest. Ive been experimenting with my 130 last night, and looking into the effect of masking the primary mirror down by one stop (to 110mm) to increase the size of the (initial) coma free field.... but slightly altering the spacing on the SWCC to increase the reduction factor so no actual photographic speed is lost. Logic being, if the field has less coma in the first place - then the corrector "should" be more forgiving on the spacing as youre not asking it to correct the usual amout of coma. This is only to see if it affects the very far corners (usually just one corner) of my images, where it starts to fall off. If a small gain can be found, it might be worth it. If it refuses to work well enough with the SWCC, I'll go back to the Baader and see what happens. Could go horribly wrong, but if you dont ask - you dont get!
  16. Leave it switched off and create calibration frames at another time (but taking care to re-create the ambient temperature conditions if poss), as you dont really want the camera processor messing too much with your data. Advantage of this method is that you now have a library of calibration files (at different settings) you can use over and over again.
  17. I believe they might be probably best to ask them.
  18. Well... its been a while But, after some initial fiddling and a couple of nights that were actually clear - I now have the first "proper" image from this lens/telescope hybrid. Currently, I have the lens stopped down to f5 while I investigate a couple of things. Havent properly tried a mosaic with it yet either, that will be its true test of flatness. Askar ACL200 @f5, QSI683, Astrodon Ha
  19. Ok, I've had a couple of decent clear nights so I can post the first "proper" image from it. However, I must confess I had to stop the lens down to f5 in order to clear up some of the corner troubles on the KAF8300 sensor (22mm diagonal). 25x600s - QSI683 - Astrodon Ha
  20. More testing, but the sky was on/off a lot so it took seemingly forever to balance the field in Ha: About 20min in Ha
  21. Still a long way to go, I have to find out how this thing reacts when I want to build a mosaic. The corners need to be 100% perfect for the overlap to work correctly.
  22. This was taken with the lens wide open. When you have exact focus you will always get diffraction spikes - they are caused by the clips that hold the lens elements in place (its a very common occurance). The adjustments required however to get to this stage are very...very... fine. On a centrally focused star there was a little corner distortion (though equal and distribited evenly) - but if you move the star 2/3rds of the way out to the corner, then refocus it flattened the field out. Not really half the story really though. Ive only gotten to this stage because I swapped out my adaptors twice, then had to install a 50 micron (0.05mm) shim on the camera becuase it had a bit of tilt. Still more adjustments to make though, I had the spacing set to 56.5mm - but I think at least 0.5mm can come off that.
  23. My work is done... im going to bed...lol.. 10x120 (L) QSI683
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