Advice please - I just can't get star colour - argh!

[Fordos Moon]

Morning All.

I really am struggling to achieve any star colour with my modified Canon 1100D (and Astronomik EOS Clip-Filter CLS).

Here is my latest effort, the double cluster in Perseus. This was 47 x 90 seconds using the above and the ED80.

I have tried processing using a number of tools available post Deep Sky Stacking. This image is the best of a bad bunch.

In Photoshop I have used the Astronomy Tools "increase star colour"; various online turorials to process star cluster images etc but I just can't get any colour in my stars other than Red!

The unprocessed output from DSS showed a little "orange/red" colour on 3 stars towards the lower half of the picture but any processing destroyed what little colour I had.

Any help would be appreciated.

regards, Desperate Bob ;-)

[VigdisVZ]

In Deep Sky Stacker, try bumping saturation to 25%. Also the double cluster contains very few "blue" stars. Many reference images, including my last try has a false blue in it for esthetics. But you should at very least be able to get some orange out of some stars.

Best way I've found is to fidget around with channels in DSS to get a balanced image, then bump saturation to 20-30% then save a 32 bit tiff, open in phothoshop, convert using exposure/gamma (not local adaption) to 16 bit and take it from there.

It's a whole new beast for me to process astrophotography, struggling at times to get my head around the workflow, and I've been using photoshop off and on for 20 years now. Only the last 2 or so DSO images (out of a total of roughly 8 tries) has yielded a result I started to get happy with and it's been over 2 seasons now. So what I'm trying to say is keep doing it, keep experimenting, dont give up.

[VigdisVZ]

Also what ISO? And try the different settings in DSS for whatsitsname... Background Calibration.

[jgs001]

When you save from DSS, are you saving with adjustments applied or embedded ? If applied, then this is to be expected... DSS operates on the images as if they are grey scale (you can see that mentioned during the stack), and to get the colour to appear you need to boost the DSS saturation slider by between 20 and 25%. Better to process the resulting image in PS, after saving with the adjustments embedded though. When you're stretching, watch out for the highlights, and that you don't blow out the cores (easy to do).

Are you having DSS set a custom white balance or just leaving it to it's own devices ? This may cause you oddities, thanks to the blue tint of the CLS.

[Fordos Moon]

In Deep Sky Stacker, try bumping saturation to 25%. Also the double cluster contains very few "blue" stars. Many reference images, including my last try has a false blue in it for esthetics. But you should at very least be able to get some orange out of some stars.

Best way I've found is to fidget around with channels in DSS to get a balanced image, then bump saturation to 20-30% then save a 32 bit tiff, open in phothoshop, convert using exposure/gamma (not local adaption) to 16 bit and take it from there.

It's a whole new beast for me to process astrophotography, struggling at times to get my head around the workflow, and I've been using photoshop off and on for 20 years now. Only the last 2 or so DSO images (out of a total of roughly 8 tries) has yielded a result I started to get happy with and it's been over 2 seasons now. So what I'm trying to say is keep doing it, keep experimenting, dont give up.

Thanks Carl, I will give it a go after work. I used ISO 800. It's the orange I'm after, I didnt realise about eh false blue. I will follow your process step by step, these are all things I was unaware of. I normally line up the RGB histograms in DSS and go from there. My red histogram is always twice as fat, if not larger than the blue and greens.

[Fordos Moon]

When you save from DSS, are you saving with adjustments applied or embedded ? If applied, then this is to be expected... DSS operates on the images as if they are grey scale (you can see that mentioned during the stack), and to get the colour to appear you need to boost the DSS saturation slider by between 20 and 25%. Better to process the resulting image in PS, after saving with the adjustments embedded though. When you're stretching, watch out for the highlights, and that you don't blow out the cores (easy to do).

Are you having DSS set a custom white balance or just leaving it to it's own devices ? This may cause you oddities, thanks to the blue tint of the CLS.

Thanks John. I save one without settings applied and one once I have moved the histograms/sliders, as TIFs but i must check if 32 or 16 bit as I didnt realise that could ne an issue. Also this time I did not boost the saturation for fear of increasing the red but I will do that tonight. Just to clarify, "saving with adjustments embedded" is that the same as "saving once I have moved sliders, shadows, highlights etc" in DSS?

Also I have left DSS to its own devices. How do I get DSS to set a custom white balance please?

[jgs001]

Saving with adjustments embedded means no matter what you do with the sliders, they have no effect on the image that gets saved out. The image will look, fainter, potentially blank, when loaded into PS. My image of M31, for example, looked like 2 blobs (galaxy cores), and nothing much else, it was the processing in PS that pulled the data out.

For DSS to create a custom white balance, (these are the settings I use with DSS with my Canon dSLR and a CLS clip filter)

The titles of each page show the settings to look for 

This setting is lower left in DSS, you're looking for the white balance setting.

The link at the bottom of the stacking mode is the important bit in the next one.

[MattJenko]

If you are going to do processing in Photoshop afterwards, why would you do ANY processing in DSS other than stack the images? Genuine question.

[Owmuchonomy]

If you are going to do processing in Photoshop afterwards, why would you do ANY processing in DSS other than stack the images? Genuine question.

Agreed. I stay well clear of any DSS processing and send a 16 Bit file straight to PS.

[Owmuchonomy]

Morning All.

I really am struggling to achieve any star colour with my modified Canon 1100D (and Astronomik EOS Clip-Filter CLS).

Here is my latest effort, the double cluster in Perseus. This was 47 x 90 seconds using the above and the ED80.

double cluster.JPG

I have tried processing using a number of tools available post Deep Sky Stacking. This image is the best of a bad bunch.

In Photoshop I have used the Astronomy Tools "increase star colour"; various online turorials to process star cluster images etc but I just can't get any colour in my stars other than Red!

The unprocessed output from DSS showed a little "orange/red" colour on 3 stars towards the lower half of the picture but any processing destroyed what little colour I had.

Any help would be appreciated.

regards, Desperate Bob ;-)

The best tutorial I have found so far on this was Pete Lawrence's in October 2013 Sky at Night.  I only have a hard copy so can't post a link but it may be out there.  His tips concentrate on avoiding saturating stars (which is why they seem to lose colour) in DSLR photos by reducing ISO.  He recommends sticking at ISO 200 for example and thus increasing the well depth of each pixel.  He uses PS subtraction techniques to bring back the colour from the outer edges of stars where it tends to remain when cores are saturated.

[lensman57]

Morning All.

I really am struggling to achieve any star colour with my modified Canon 1100D (and Astronomik EOS Clip-Filter CLS).

Here is my latest effort, the double cluster in Perseus. This was 47 x 90 seconds using the above and the ED80.

double cluster.JPG

I have tried processing using a number of tools available post Deep Sky Stacking. This image is the best of a bad bunch.

In Photoshop I have used the Astronomy Tools "increase star colour"; various online turorials to process star cluster images etc but I just can't get any colour in my stars other than Red!

The unprocessed output from DSS showed a little "orange/red" colour on 3 stars towards the lower half of the picture but any processing destroyed what little colour I had.

Any help would be appreciated.

regards, Desperate Bob ;-)

Leave the " processing " side of the DSS alone. It is only intended as a rough visualization  tool and not for processing. Do all your processing post stack in PS or something else. DSLR captures are quite difficult to colour balance properly for a lot of reasons including relatively low well depth which causes early saturation of the core.

A.G

[michaelmorris]

I too have been struggling with star colour on my modifies Canaon 1100D.  I'll re-read the Pete Lawrance article on star colour with interest.  Can you remember which month's issue of S@N magazine it was in?

[michaelmorris]

Interesting article that may be of use.

http://www.astropix.com/HTML/J_DIGIT/STARCOLR.HTM

[Owmuchonomy]

I too have been struggling with star colour on my modifies Canaon 1100D.  I'll re-read the Pete Lawrance article on star colour with interest.  Can you remember which month's issue of S@N magazine it was in?

As per original post; October 2013.

[michaelmorris]

As per original post; October 2013.

Note to self - read postings properly![emoji4]

[laser_jock99]

All the best star colour photos seem to come from LRGB imaging. DSLR/OSC is always going to be a compromise.