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Uranium235

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Everything posted by Uranium235

  1. 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
  2. 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.
  3. Thats a depressing amount of satellite trails =/ and its only going to get worse
  4. 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)
  5. 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 impossi
  6. 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
  7. 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.
  8. 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
  9. 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
  10. 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
  11. 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.
  12. 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 ad
  13. First test image, barely time to get 8x30s (L) on Sadr - then the clouds return
  14. lol... should have kept my mouth shut... jinxed it Oh well, maybe tomorrow night.
  15. 3 min into the first 10min sub.... just need it to stay clear for another 7min...lol I think I will need a better B-Mask, the one im using is fine in LRGB but it gets a bit difficult with Ha. In the end I just focused on red, should be close enough (hopefully).
  16. Hmmm... looks like it might not be happening. Soon as I put the mount out.... clouds.
  17. Looks like it might be on for tonight. But its going to be a short tun, by the time I get home I would have been working for 14 hours, no way have I got the legs for a late nighter..lol A couple of hours in Ha should be enough for a quick look to see if everything is as it should be. I'll just point it at Sadr and fire away with reckless abandon...lol... should get something interesting,
  18. Next time I take it out, I'll give the dew shield a ding for ya It back under wraps for the next few days atm, its looking like at tleast Thur or Fri next week before it clears up. The actual lens cap is the only plastic part on it which probably accounts for its weight.
  19. Oh btw, I'll probably do another video once I have actual data to work with. My son is quite interested in being the cameraman...lol. (and I promised I'd teach him video editing)
  20. Unfortunately, I dont know anybody local with such a camera (35mm). And its going to be pretty much "grab and go" short notice sessions. If it satisfies the KAF8300 and APS-C to the point where you really cant tell the difference between the two (in terms of flatness) - theres a high chance it will be good with something larger... but thats just speculation at the moment. Lets just get it up and running, and see whats what. Edit: Dont forget, there have been many claims in the past where the manufacturer states that its good up to 35mm. (or beyond).. but thats rarely been
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