Cannot Debayer images

froggy1001

Rosette Nebula.jpgHi,

Having changed my previous ASI 071 for a Pro version to deal with the condensation issue I am now faced with a problem I never experience before.

Can anyone shed some light on this issue.

I took 40 frames of 300 seconds each and everyone of them are different when Debayered. Some have a green cast which I expected some have some red cast and the others have a multi coloured cast. I have attached a picture of the worse one.

Thank you for looking.

Vince

froggy1001

As anyone got any idea as to what the problem could be. Is the camera faulty?

Thanks

Vince

bent

Hi Vince,

I had the same problem when I had the 071. I finally figured out that I needed to perform demosaic prior to align and combine since the align and combine process shifts each image a bit.

Ben

PS- I'm new to all of this so take what I say with a grain of salt. With the new Pro version I'm still trying to figure out the best demosaic setup but a least Im getting consistent output. Let me know if you discover anything useful.

Ben

froggy1001

Thank you Ben for the advise.

Vince

Sam@ZWO

we will look into this problem when we get back to work

froggy1001

Thank you for your answer. Happy and Prosperous New Year.

Vince

froggy1001

I have been trying all kind of variations on this image and I cannot get a correct colour image. The only way I can get near is by not using any correction frames at all. (Dark, Bias or Flats) Debayer as advised needs to be done as a first action and then align and integration. If I use calibration or cosmetic correction everything then goes to pot.

Hopefully you will have an answer to my problem.

Thank you.

Vince

bent

Remember I’m a rookie, but I think think things work best if you do everything EXCEPT align and combine BEFORE you debayer. Anybody feel free to correct me if I’m wrong. Nebulosity’s 4.0 manual does a good job of explaining the reasons for doing things in order.

froggy1001

Thank you for your answer. Unfortunately if I do anything before debayering I cannot get any image with a correct colour. The only thing which may work badly is no correction frames of any king and debayering immediately. I am stuck with being able to debayer and then process the image with all the imperfection.

Vince

bent

Vince, Did you see this topic: https://bbs.astronomy-imaging-camera.com/viewtopic.php?f=21&t=7780

Before I did this I had massive color cast issues. Unfortunately, I haven’t been able to check if it carries over into night sky imagining yet due to lack of significant clear sky opportunities. But at least the land based images look fine.

Ben

mahaffm

I have this same exact issue. I upgraded my ASI071 to the pro version. I always preprocess using DSS, (DeepSkyStacker) and PixInsight to post process. prior to the upgrade my images always had a green cast that was removed during post process, via the ABE, (Automatic Background Extraction), tool in Pixinsight. Now I get this really deep red and even after ABE a lot of this red is still present. In addition, the colors don't appear to be correct as well as being very dark, difficult to bring up the brightness during processing.

Background, I'm using SGPro 3.0 and the ASCOM driver, not the built in native ASI driver built into SGPro. Also, I was able to image a few time using a previous version of SGPro, 2.X, and never noticed this issue. So I don't know if this issue is with SGPro or ASI?

Regards,

mahaffm

froggy1001

mahaffm

This is exactly what I get. So maybe it is not me.

Thanks

Vince

mahaffm

I think on our next clear day/night, not sure when that will be, I'll play around with SharpCap to see if the images coming in looking correct. Maybe I will do some daylight images to see if the colors are correct in both Shartcap and SGPro. Just a thought to see if the issue is software related, (SharpCap, SGPro), ASCOM, hardware or me. I'm still wondering if its something I'm doing since only Vince and I are the only ones having this issue. I think I need to get more information before I think anyone would be able to help. I would be interested to here for other ASI071 Pro owners to know if they are or are not have this issue.

Regards,

mahaffm

Sam@ZWO

can you tell us how many frames do you get have such problem?

mahaffm

Sam wrote:
can you tell us how many frames do you get have such problem?

Hi Sam,

Thanks for the response.

I don't know how many frames have this issue. I typically take anywhere from 50 to 100 images. I take the images and use the Image grader in SGPro to weed out the "Bad" ones. I then use PixInsight "Blink" to weed out anything that is cosmetic, Satellites or Air planes streaks. I do not debayer anything prior to stacking.

Based on you question, I'll take each image and debayer. Once debayer, I get a count to see how many have the issue and will report back. Most likely I will not be able to get this started/done until the weekend.

Regards,

mahaffm

froggy1001

I image the Rosette Nebula a week ago and I took 40 frames of 5 minutes each. Of the 40 frames 10 were an even colour across the image the other 30 images were multi-coloured.

Vince

Sam@ZWO

froggy1001 wrote:
I image the Rosette Nebula a week ago and I took 40 frames of 5 minutes each. Of the 40 frames 10 were an even colour across the image the other 30 images were multi-coloured.

Vince

can you upload 2 or 3 images with good and bad?

froggy1001

Rosette 1.jpgHi Sam

Here is a couple of pictures showing the problem.

Thank you

Vince

mahaffm

Hi Sam,

I was able to do some testing on my images and the problem appears when I include the Dark Frames. If I process my images using Darks, Bias and Flats I get this "RED" Cast. When I do the Automatic Background Extraction in PixInsight I get a very strange image that I cannot process.

However, If I don't use Darks but keep Bias and Flats I can process the image as I normally can. The only exception is that I now have hot pixels since I'm not using any Darks.

It appears something strange is going on when Darks are included. Can it be possible, since I take these Darks as part of my Sequence using SGPro, it's possibly a issue is with SGPro Darks? I never had this processing issue prior to the ASI071 upgrade to the Pro but I also upgraded to SGPro 3. So I had two changes and don't know which if either has caused this issue.

Just looking for some guidance on what to do or try next.

Thanks,

Mark

Sam@ZWO

SGP3.0 support ASI cameras naively

I think maybe the image from ASCOM and native support have different order

so you can try still connect our camera through ASCOM to get some light frames