SGPro newbie color question


#1

Hi,

My typical post processing workflow is to batch save and convert -calibrate with flats, darks and bias cals, then batch process to run a color convert module on each calibrated frame and finally to align and stack, all in Maxim DL. I’ve been playing with SGP with my Nightscape 8300 OSC for a few nights now and I notice the following. The raw FITS images I get don’t color convert correctly, everything is a gray/green monochrome. I compared Rosette and M1 taken from a few months ago in AstroFX to what I took last night with SGP and the raw untouched files right off the CCD look different when I just run the color convert module on them in maxim dl, even uncalibrated. I did this with previous images and you see the red Ha as you would expect but not with the SGP images. I can’t find any setting to change that might fix this. Any idea what I’m doing wrong?

Thanks,
Tom


#2

Maybe you are using the wrong Bayer pattern? I’m not sure and we don’t really deal much with processing. You didn’t try to bin your images did you?


#3

I’m not sure where I can change the Bayer matrix. Maybe I do have to change the way I process the images when I take them with SGPro? I believe I saw a similar thing when I tried to use Maxim DL to run this CCD. I seem to have the best results with AstroFX, the Celestron sw that came with the CCD. I can try MDL and see if it does the same thing as SGPro, maybe that will tell us something.

Thanks,
Tom


#4

This is almost certainly true. Any capture program can return a slightly different width of image… cut out overscan areas, leave them in, etc. Any of these can influence the bayer pattern you will need to use. Unfortunately I cannot help you with settings in Maxim, but there are only 4 possibilities and they almost certainly provide you access to them.


#5

Hi,

I took 3 shots just now of M1. From Left to right, SGP, AFX, MDL. The MDL one had a auto dark of 5 mins added to it looks the best as you would expect. All three look like monochome when I open them in MDL, when I color convert them, this is what I get.

Please help me make this work! I want to buy SGP, I’m into the automation.

Thanks,
Tom


#6

I can’t say I’m familiar with the Debayer routine in Maxim but you likely need to change the Bayer pattern. Generally these are specified like RGBG, GRGB, RGGB. SGP may be reading the image differently than the other two or it may be shifted a column or two depending on how you captured. I’m assuming that you used a native driver with AFX, the ASCOM driver with SGP and what about Maxim? Was this also native driver?

Thanks,
Jared


#7

I have the Celestron Nightscape driver installed, it included an ASCOM driver as well. I’m pretty sure all 3 are using the same driver to talk to the CCD. MDL is real powerful and I barely know how to do what I do with it, maybe there is bayer setting that i can flip that fixes this, I’d be happy with that, I’ll look.

Thanks,
Tom
http://jropics.com


#8

In the convert to color module in MDL you can pick the CCD which changes the way it converts to color. Trying the different cameras MDL supports I found that setting my CCD to SBIG seems to do a pretty good job with my SGP acquired images.

The center 2 are converted with the SBIG profile, the rightmost was an AFX shot converted with the nightscape profile that I have been using as reference. Leftmost was SGP converted with nightscape profile and the top smaller one is it unconverted with the Convert Color dialog box operating on that image.

I think I can work with this using the SBIG profile. Thank you all so much!

Tom


#9

Tom, glad you got it working! Looks really good.

Chris


www.mainsequencesoftware.com