jjosefsen

What scope did you get Adam?

Sensor analysis Hypercam 1600M Pro TEC Sensor Analysis - Sheet1.pdf

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.

Calibrated and registered .fits

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.

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.

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?

😱😂

100/100 fiber 😉

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

Tried the power supply it came with, and running it through my bench PSU + Pegasus Astro PPB - same thing..

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..

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.

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..

Well s**t.. I guess it is not supposed to look like this then..

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.. 🤨

Brilliant - thanks for that explanation. 🙂 What do you think of the overcorrecting flats hypothesis?

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?

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..

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?

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.

Thanks for looking guys.. Here is a set of 5x(lights, flats, darkflats and darks) Data The offset theory is quite interresting, I was reading something you wrote in another thread @vlaiv but, but I'm not sure i completely followed.. When I used the 130PDS for a short while, I calibrated out what appeared to be a worse vignetting with my DSLR, so I don't think the filters should cause a problem with this slow scope.

Yes exactly the background, I should have been clearer, sorry. There was moonlight yes, taken on Sunday, so 50% illuminated moon. But wouldn't the gradient be smoother from one side to the other?

Hi, So I've bought my first cooled astro camera, an Altair Astro Hypercam 1600M, based on the same Panasonic chip as the ASI1600MM.. I'm honestly not even sure if I have an issue with the data, or if it is just PI's autostretch that just over does it.. But this is what it looks like: In contrast this is what a calibrated single frame looks like with a default autostretch: The single sub looks fine I think, but the integration just looks strange, but also like it is over stretched by PI. For the record the results are the same whether i use PixInsight for calibration and stacking or if I use Astro Pixel Processor. I have tried many, many different stacking and normalization settings, and nothing changes it. I am using 1.25" filters at F6.4, and with the substantially increased back focus of this camera (17,5mm) compared to the ASI1600 (6,5mm), I thought it might be vignetting, but I don't think it shows in the single subs.. Details: AA Hypercam 1600M Baader 1,25" filters in EFW mini. Evostar 80ED @ 520mm 90s exposures Gain 350 (about unity) -15c Offset 48 Calibrated with Flats exposed to 50% Histogram, Darks matching lights and DarkFlats matching flats and a bad pixel map. All calibration frames in stacks of 50. Link to Green master stack: 67 minutes Green master Link to Green filter master flat: MasterFlat Green Link to 90s master dark: Master dark 90s I look forward to hearing what the experts think, something to worry about or not? Thanks, Johannes

I believe the drivers are installed when you install Altair Capture, so grab the latest version of that. Alternatively try out NINA https://nighttime-imaging.eu/