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DSS Losing Colour


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Hi

Got an hours worth of Lovejoy lastnight but when I stack it in DSS all I get is near grayscale output.

I have searched the forum and read the previous suggestions of boosting the RGB channels and saturation, saving the final image with "embed adjustments but do not apply them" but nothing makes any difference.

The single sub jpegs have plenty of colour and far better than stacking the hours worth of RAW data.

And before anyone says it, there is star trailing and hideous coma and vignetting. :eek:

I have stacked in DSS before, M45, well most of it, and it had colour. So I restacked the same previous data to rule out a configuration problem in DSS but it outputs as before with colour.

I would really appreciate some help, what am I doing wrong?

This one of the 3 minute subs in jpeg

post-36192-0-86330600-1421491430_thumb.j

Many thanks

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Almost all my stacked images in DSS look rather grey/desaturated. To regain some color i click the saturation slider in DSS once (which sets it to 20%) and then the color is back. In the saving options i check the "apply to ..." option. Did you try that?

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Thanks.

I homed in on this response in that thread. I have seen it before but not quite taken it in...

"Yes. DSS reduces the colour for me as well.

I export the image as a FITS image and then use FITS Liberator to optimise the RGB channels. They are then brought in to CS2"

I can't try it at the moment but is this what worked?

Incidentally I tried stacking the jpegs from the run, so glad I saved the subs as raw+jpg, and lovely colour. Would this suggest a problem interpreting the Bayer information from the raw files?

I'll give the above a go. If it doesn't work, if I post a link for the autosave.tif would someone be willing to see what they can pull from it?

I'd love to get this sorted.

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OK, so I saved the final stacked image as FITS and opened it up in FITS Liberator.

The image definitely appears to be gray, the only adjustments I have are black and white no RGB at all.

This looks more like NO colour as opposed to REDUCED colour.

It would seem that DSS is not debayering the raw files.(Based on my very limited understanding of the subject)

Any ideas??

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What settings have you got in DSS?

What colour are you expecting?

You have to work on the colour, my DSS images are pretty bland when I first start post processing.

Here is a typical Autosave out of DSS and the second image is after post processing.

This was 3x600secs stacked.......M38 and friends.

post-30455-0-28156500-1421741873.jpg

post-30455-0-09161700-1421741890.jpg

Edited by wxsatuser
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Thanks Mike, first off, awesome image!

That preprocessed image does have some colour, mine had none.

But the good news is I think I may have solved the problem.

It looks like it was down to the debayering being done in DSS, or lack of it, and the reason appears to be user error :embarrassed:

In the RAW settings under bayer matrix transformation I had "use bayer drizzle algorithm" selected, I have changed this to bilinear and I think it is now working as expected.

Just doing another stack to see what the result is but the preview of each raw before stacking now has some colour whereas before they were grayscale.

Doh! Sorry for wasting everyone's time on this. Still so much to learn.

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I've had a similar problem with processing RAW files and always found the JPEGS to be better. Now, the first thing I do is convert the RAW files to TIFF before processing with DSS. I also make sure the RGB is aligned by checking the RGB levels box before stacking. The processed file seems to always be a little on the grey side initially but this is simply addressed by importing to Photoshop and adjusting Levels there.

Hope this helps.

David

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I've had a similar problem with processing RAW files and always found the JPEGS to be better. Now, the first thing I do is convert the RAW files to TIFF before processing with DSS. I also make sure the RGB is aligned by checking the RGB levels box before stacking. The processed file seems to always be a little on the grey side initially but this is simply addressed by importing to Photoshop and adjusting Levels there.

Hope this helps.

David

Thanks David.

What do you use to convert the RAW files? I tried converting the RAW to dng and that doesn't work either.

Sorry what do you mean by "I also make sure the RGB is aligned by checking the RGB levels box before stacking"? Is this in DSS or elsewhere?

This is getting so frustrating, it takes ages to keep trying something only to find out it hasn't worked again.

:confused:

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Rich

I have a Canon EOS 100d and so I use a programme called Digital Photo Professional, a utility that came on the disc with the camera. I believe there are also free programmes available on the net which can also do it.

As for aligning the channels, I do that in DSS. When you select 'Stack Selected Pictures', a dialogue box pops up. Select 'Stacking Parameters' and another box pops up that has 6 tabs. It should have the 'Result' tab selected but if not, open it. There should be a number of check boxes, one of which is 'Align RGB Channels in final image'. Ensure that is checked.

Hopefully that will help.

David

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Rich

I have a Canon EOS 100d and so I use a programme called Digital Photo Professional, a utility that came on the disc with the camera. I believe there are also free programmes available on the net which can also do it.

As for aligning the channels, I do that in DSS. When you select 'Stack Selected Pictures', a dialogue box pops up. Select 'Stacking Parameters' and another box pops up that has 6 tabs. It should have the 'Result' tab selected but if not, open it. There should be a number of check boxes, one of which is 'Align RGB Channels in final image'. Ensure that is checked.

Hopefully that will help.

David

I was already ticking that box but didn't make the connection with your post. That's at least one thing I am doing right.

If you use JPEGs or DNG you can't use darks etc.

Just load images and click recommended, best not to alter anything until you actually get an image.

Dave

I've used darks darks with dng before. It doesn't warn you when using them like it does with jpegs. What's the thinking behind that?

I'm clicking on recommended settings and setting everything it suggests. It's what I have always done, but for some reason this Lovejoy data just isn't having it.

Appreciate your help with this.

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I assume that your pictures were taken using the 600D? There is a large school of thought that when using a DSLR that there is very limited benefit to using darks since the temperature that both they and the lights are taken at cannot be regulated to the same level. This means that you will not get rid of all the noise present and may in fact introduce it. However, bias frames and flats will always help.

The last two pictures I have posted are with a DSLR, although it is modded, they have no calibration frames whatsoever. See what you think.

http://stargazerslounge.com/topic/234582-running-man-with-modded-100d/#entry2539161

http://stargazerslounge.com/topic/234026-horsehead-with-modded-100d/

They were done with the same settings and file conversion I explained above.

David

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