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jjosefsen

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Everything posted by jjosefsen

  1. There is a lot of talk about these sattelites on twitter right now, particularly among astrophotographers.. 12000 of these suckers in orbit does sound quite unnerving, but I will reserve judgement until we see them in their final orbits. Thanks for sharing!
  2. At f7 probably not a problem.. But i don't know about after reducer is added.. It might be a problem, and if you have to get new fw and filters it will drive the price up.
  3. Hi, It has been a bit of a ride to be honest.. I have had some problems with calibration, but due to lack of astrodarkness here, I have had very limited chances to acquire new data. I do believe I have the calibration problems under control now, so looking forward to late summer / autumn so I can start imaging again. There is some random noise that I just can't figure out, and due to it's random nature the only way I can see to get rid of it is by swamping it with enough signal and then dithering, something I would do regardless. The backfocus has not been an issue yet, but I have a quite slow system @F6.4 and I think it will be a problem when going faster with 1.25" filters. I haven't done enough testing yet, I've had two sessions with it - one with a full moon and one with around 60% illuminated moon and some hih thin clouds.
  4. Little update here.. I got a new laptop for work recently after the dock died or my old one.. So decided to try and test the camera on said laptop instead of my older imaging laptop.. Look at the "read noise" that I was getting on the left side.. Pretty much gone on the new laptop!! Same settings, same cables - haven't even touched the camera between these shots. So... Researching to see if there is something I can do to clean that noisy USB connection up, or if I need to look at another imaging laptop.. I even tested it on my "old" work laptop and it had the same issue as my imaging laptop, so I concluded it wasn't computer related..
  5. Sensor analysis Hypercam 1600M Pro TEC Sensor Analysis - Sheet1.pdf
  6. Thanks a lot guys, really appreciate you knocking around with this data so much. It's hard for me to judge if this is within what can be expected from the camera, if it is me doing something wrong, etc.. I will share the results of the sensor analysis i did in sharpcap when I get home, that should provide more info on the sensor and why I chose gain 350.
  7. Not much change unfortunately.. Result and 10 calibrated and registered lights (.xisf) Linear Fit Rejection, Standard normalization: Linear Fit, No Normalization: I still don't think it can be prescriped to light pollution, something still broken.
  8. I already tried doing a whole manual workflow in PI, where I have much more control over the subs, but I accidentally deleted everything earlier. My master dark at the time included the darks with the "too low temperature", so I can try again without - tomorrow as it is getting super late! And will do it without any pixel rejection in the dark flats and darks, there are no cosmic ray strikes any way. I discovered the "unstable" bias or read noise a while ago, but as it can be "swamped" I figured I could live with it. Also did a lot of tests with different capture software, power supplies, cables, etc.. to see if anything external was causing that "flicker", but I didn't find any, so as you say it must be in the camera electronics.
  9. It was the stats from the result.. Here are the files. I had the Amp Glow Reduction / Dynamic pedistal feature turned on in APP, could be the reason. Or I am doing something funky with the statistics process in PI. Dark-Dark But can we conclude that the Dark substraction works? That would leave Flats calibration right?
  10. I'm pretty sure that just how the PI script exported the statistics. No trouble for me at all, i'm just grateful for the help! Darks
  11. Tried the power supply it came with, and running it through my bench PSU + Pegasus Astro PPB - same thing..
  12. And that is why I'm again having this nagging feeling that something is off here..! But that banding noise does dissapear in lights, if exposed enough.. But if dark substraction throws it back in there then..
  13. I redid the dark - dark substraction test, as I realized I hadn't omitted the two where the temperature was a little off. Same result.. Here is a link to a google sheet with the dark frame stats, nothing sticks out to me. Dark frame statistics I think I need to find someone else with this camera, to compare their findings.
  14. Split dark stack into two.. Calibrated with average and sigma clipping - both stacks. Subtracted one stack from the other, that was the result. No much glow left, but alot of banding on the left side..
  15. Well s**t.. I guess it is not supposed to look like this then..
  16. Are you referring to one or two darks being at a lower temperature? I would imagine that 1 or 2 subs out of 50 wouldn't make too much of a difference? In either case I did try a master dark without those subs included, and it did not make a difference. I will keep working on it, but I am really stomped here..
  17. Brilliant - thanks for that explanation. What do you think of the overcorrecting flats hypothesis?
  18. So this is without flats calibration: And the image looks like you would expect from an image without flat calibration, but it does looke like the uneven background might be comming from the flats instead, like overcorrecting. On another note: Mean of 90s dark with Sharpcap: 1071 (16bit) Mean of 90s dark with NINA: 67(16bit) What is that about?? Edit: Wait, 4^2*67 = 1072 <-- Thats the right way to convert fra 12 bit to 16 bit right?
  19. Yeah I know. Was just interrested in seeing if increasing it would make a difference with minimum values. I am running a set of 90s darks with SharpCap now..
  20. I just tried doing 5 90s darks with offset 64 and 5 0,5s darkflats with offset 64. The minimum value of a dark frame is now 7 compared to 1 in pixinsight statistics process. The minimum value of a darkflat is 29.. As you say, one would expect there to be more noise in the dark versus the darkflat. Could it be some kind of on camera calibration that isn't switched off in the capture software?
  21. I can definitely try that tonight. When I used my fan cooled 183m camera I also used darks, but these could easily vary over 1-3 degrees in temperature compared to the lights, and never showed this kind of problem. But I will do a "clean" stack tonight.
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