Working with 32 bit images

[Alien 13]

15 minutes ago, Stub Mandrel said:

Thanks William and Silverastro.

I think the best solution for me (and perhaps anyone else ona budget) will be to open DSS files as 32 bit in gimp, stretch with levels and curves to maximise the dynamic range without losing fainter detail, then save as 16 bit and finish using PS (to benefit from the plugins and actions).

Paintshop Pro claims to have 16-bit filters so might be better than using PS CS2, but it 'forgets' my gradient exterminator key and doesn't have Noel's actions...

Why not do the initial stretch using DSS itself, I find the sliders give far better results than anything I can to in PS etc.

Alan

[Stub Mandrel]

8 minutes ago, Alien 13 said:

Why not do the initial stretch using DSS itself, I find the sliders give far better results than anything I can to in PS etc.

Alan

That's what I do now, but I have been cruelly abused for admitting to doing so

[Alien 13]

1 minute ago, Stub Mandrel said:

That's what I do now, but I have been cruelly abused for admitting to doing so

I used to use the sliders in DSS and save with them applied as a quick check on an image but found it impossible to get even close using the "proper" method.

Alan

[GraemeH]

As has been stated by others, Photoshop has limited capability with 32 bit images, but you can use levels adjustment (but not curves), and Gradient Xterminator also works on 32 bit images.  This might help for at least getting a good colour balance before converting to 16 bit.

[Stub Mandrel]

36 minutes ago, GraemeH said:

As has been stated by others, Photoshop has limited capability with 32 bit images, but you can use levels adjustment (but not curves), and Gradient Xterminator also works on 32 bit images.  This might help for at least getting a good colour balance before converting to 16 bit.

I can get Gradex to work on an autosave.tif. but not levels.

When converting to 16-bit I get exposure and gamma controls. Seem to be a bit clumsy.

My experiment (with rosette data) ended up with colourful stars and virtually no nebula :-(

 

[Stub Mandrel]

I had another try, this time I moved exposure right and gamma left until faint detail appeared.

Aside from the fact a wire causing the camera to rotate makes this look 'swirly', I can see promise in this approach.

[Stub Mandrel]

Finished off using astra image...

 

[SilverAstro]

6 minutes ago, Stub Mandrel said:

Finished off using astra image...

Nice one

or ,, wot no gimp involved ? drat, thort we woz about to catch a new recruit LOL!