Question on Deep Sky Stacker

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heyjojos
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Question on Deep Sky Stacker

Post by heyjojos » Wed Jun 10, 2015 5:48 pm

Hi
Need some advise on DSS... I was stacking some 16 light frames (RAW format) of a milky way shot I took along with dark and bias frames. The setting I used was the recommended settings from DSS. The resultant image is a very blend/ monotone TIFF image. I understand this is rightfully so (??)...

However, when I tried to post process it using Lightroom, I wasn't able to pull out the colours. The picture of MW remains blend and rather monotone. In fact, I realised that the post processed image of my one single shot is probably much nicer.

What did I miss in DSS that I should have included? Any help is appreciated. [smilie=confused.gif]

HJ

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Sivakis
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Re: Question on Deep Sky Stacker

Post by Sivakis » Wed Jun 10, 2015 10:23 pm

After the stacking, you should be faced with RGB/K Levels, Luminance and Saturation tabs.

The Saturation tab pulls out the colours. Try pushing it to around 14 - 16.

You can refer to Steve's guide here:
http://www.stevebb.com/deep_sky_stacker.html

heyjojos
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Re: Question on Deep Sky Stacker

Post by heyjojos » Thu Jun 11, 2015 9:21 am

Hi Sivakis
I tried and use the same settings as recommended but still achieve the same output. I have included a screenshot for reference (pardon the small image due to file size limitation). I also noticed in the Luminance tab, that I'm not able to get a S-Curve... Adjusting the Dark slider has no effect... FYI, I have included Light, Dark and Bias frames and confirmed they were all checked. :(

Appreciation the help.

HJ
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Sivakis
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Re: Question on Deep Sky Stacker

Post by Sivakis » Thu Jun 11, 2015 9:37 am

heyjojos wrote:Hi Sivakis
I tried and use the same settings as recommended but still achieve the same output. I have included a screenshot for reference (pardon the small image due to file size limitation). I also noticed in the Luminance tab, that I'm not able to get a S-Curve... Adjusting the Dark slider has no effect... FYI, I have included Light, Dark and Bias frames and confirmed they were all checked. :(

Appreciation the help.

HJ
The luminance tab is odd if you can't get an S-curve.

I'm not at home now so I'm just going to base this off memory:

For Darkness, Midtones and Higlights, they each have 2 sliders. I usually leave the top slider at the extreme left and don't touch them. Instead I usually have the Darkness at around 78-83, Midtones at 29-32 and Highlights at 55-60. That usually brings out what I want.

Also, looking at the Red/Green/Blue displays on the graph, you might be getting a fair amount of ambient light and that might result in the colour cast - I notice that the Green seems to be more pronounced. Try going to the RGB/K tab and play around with the Green slider (use the right arrow to reduce or expand the green width and the centre arrow to align it with the Red and Blue.

But ultimately, DSS is just a first step to get as much information as possible across multiple exposures. There are usually follow up processes in photo-editing softwares to enhance the photo further (i.e. Lightroom, Photoshop etc.). It's unlikely that you are going to be able to get a great result just from DSS alone, or rather, results from DSS can usually be further enhanced.

EDIT: Assuming that you continue to not be able to get an S-curve, that's fine. What you want from DSS is to stack multiple exposures. Since that's done, tweak it in photo-editing software to edit curves, levels, colours etc.

heyjojos
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Re: Question on Deep Sky Stacker

Post by heyjojos » Thu Jun 11, 2015 7:06 pm

Pardon the question... Really a beginner in this...

I noticed there is a message "Don't forget to add the dark frames in the stacking tab" under the Register Settings. See attached file.

May I know what that means? As mentioned, I have already checked all my Light, Dark and Bias frames. Don't understand why there is this message?

HJ
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heyjojos
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Re: Question on Deep Sky Stacker

Post by heyjojos » Thu Jun 11, 2015 7:22 pm

Another thing to note is under the Luminance tab, the max values for the Dark, Midtone, Highlight is only 10 vs the values you indicated. :(

HJ

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Sivakis
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Re: Question on Deep Sky Stacker

Post by Sivakis » Thu Jun 11, 2015 9:37 pm

No worries when you're just starting out using DSS and have questions about it - it'll be worse if you have questions but don't ask :D

I'm not sure why you're getting only a maximum value of "10". I tried to replicate this but can't.
Maybe try getting the latest DSS download here:
http://deepskystacker.free.fr/english/index.html

Regarding Register Settings, it seems that your Dark files may not be registering.

I tried a simple 3-frame stack of Lights, Darks and Bias files (like yours).
When I click "Register checked pictures", I get this:
Image

When I added the Flat files, I get this:
Image

As Steve's guide said - Green is good.

You can also refer to the frame list to see if all your selected frames are registering correctly:
Image

Once stacked, the RGB/K should show this:
Image

Move the centre arrows so that you align the Red, White and Blues and position them so that it sits just to the left of the starting curve.

In Luminance, I keep the Darkness and Highlights at "0" and keep Midtone at "10", then adjust the 2nd bar slightly:
Image

Lastly, Saturation I move it slightly to about 14, or thereabouts:
Image

Final image saved to TIF looks like this, ready for photo-editing software:
Image

Hope the above helps!

heyjojos
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Re: Question on Deep Sky Stacker

Post by heyjojos » Fri Jun 12, 2015 2:54 pm

Hi Sivakis
Thanks for the very detailed step by step guide. I think I have tried everything there is... the only suspicion i have now is that I'm running DSS on a Mac platform. Have done a bit of searching in the internet and there are some that says they can't seem to get DSS to work on a Mac :(

Thanks for your advise. Will have to try running DSS on a Windows environment and see what results I get.

HJ

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Sivakis
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Re: Question on Deep Sky Stacker

Post by Sivakis » Fri Jun 12, 2015 10:29 pm

Ah ok.

I was wondering about that. Noticed your Register pic seemed to be from a Mac but didn't think that could be the problem.

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