[rogerg (Roger)]

Originally Posted by alpal

Hi Roger,
I had a go at processing your galaxy.
What do you think?
Just edited to give more colour to stars & make them softer.
It was processed in : Fits Liberator, DSS, PS CS5, Fitswork4.

cheers
Allan

Thanks Allan, your result looks similar to what I'm now achieving since acquiring the new green data. What my attempts (and yours I think) lack is the variance of colour Rick achieved which shows that yellow dusty look together with the blue and the pink of nebulosity.

Originally Posted by atalas

Roger Its actually a very nice galaxy,and sure a few technical issues to over come but looks to me you'll get there soon!

Thanks Atlas It is a nice and interesting galaxy.

Originally Posted by nebulosity.

I had a play in Nebulosity, not much to look at compared with yours

Cheers
Jo

Thanks Jo, yeap, similar to what I'm seeing now

Originally Posted by RickS

Roger: to use the galaxy as a white reference you draw a preview which includes the galaxy, or a representative slice of it, and as little background as possible. Use that preview as the white reference in the ColorCalibration dialog. Similarly, you can use a preview of a background area of the image as the background reference.



The easiest way to boost saturation is with the CurvesTransformation process. Just select the "S" curve and play with it.

You won't want to boost the saturation of the faint areas since this will make chrominance noise and faint colour gradients more visible. A technique that works well is to extract the CIE L* (Lightness) component of your image and use it as a mask:

• use the menu Image>Extract>Lightness (there's a button you can click as a shortcut) to extract the L* component as a new image which will be your Lightness mask
• use HistogramTransformation to stretch the mask and clip the black point to protect the background
• apply this image as a mask to the original
• now apply the saturation boost (real time preview is useful to get the amount of boost right)
• remove the mask unless you want to use it for whatever you're doing next

Let me know if you have any problems. Good luck with the new data.

Cheers,
Rick.

Thanks again Rick ... I'm working through your notes and various attempts ... stay tuned!