Image Processing Practice - Raw Files Available

[ChrisLX200]

There was a thread earlier with a DropBox link for some raw files, I've started this thread specifically to make such collections available.

This is my contribution:

NGC7023 (Iris Nebula) in LRGB

https://www.dropbox.com/s/3pyvp9wsi50knck/NGC7023%20Iris%20Nebula.rar

Files included are FITs files for Lum, Red, Green, Blue and also Master calibration files (TIF) for Darks, Bias and Flats. Filesize 507Mb compressed.

Pickerings Triangle in Narrow Band

https://www.dropbox.com/s/bywlph2domxchgc/Pickerings%20Triangle.rar

Files included are FITs files for Ha, OIII, SII  and also Master calibration files (TIF) for Darks, Bias and Flats. Filesize 228Mb compressed.

I cannot offer all the raw FITs for calibration files because there are just too many - 50 of each type. That is why the masters only are included. You should be able to stack in DSS using these files then post-process in whatever is your favourite program (I use StarTools for the bulk of the processing, plus PixInsight when needed and Photoshop for final cosmetic tweaks).

If anyone wants to add more file sets just add as a reply to this thread.

ChrisH

[Tinker1947]

Thanks for the files, just to say they downloaded and unzipped ok.....

[hazegood]

am trying to learn this processing stuff for when I start imaging myself so thanks for the data,

I got this form the pickerings triangle,

https://www.dropbox.com/s/qnv1r1pwhtsg27y/leighpick1.jpg

am trying to get my head around what to do with the iris data, I think as there are RGB shots I should be able to get a colour image, but whatever I do in DSS its only outputting greyscale image, any hints?

Thanks again

Leigh

 

[ChrisLX200]

am trying to learn this processing stuff for when I start imaging myself so thanks for the data,

I got this form the pickerings triangle,

https://www.dropbox.com/s/qnv1r1pwhtsg27y/leighpick1.jpg

am trying to get my head around what to do with the iris data, I think as there are RGB shots I should be able to get a colour image, but whatever I do in DSS its only outputting greyscale image, any hints?

Thanks again

Leigh

You can use DSS to stack the subs from each channel (L, R, G and and that will give you a grescale image for each. Then use another program (StarTools, Photoshop, PixInsight etc.,) to combine those greyscale images into one colour image.. PixInsight will do the whole job in one go - if you know what you're doing.

ChrisH

[hazegood]

You can use DSS to stack the subs from each channel (L, R, G and and that will give you a grescale image for each. Then use another program (StarTools, Photoshop, PixInsight etc.,) to combine those greyscale images into one colour image.. PixInsight will do the whole job in one go - if you know what you're doing.

ChrisH

so I stack the red green and blue images seperatly, then combine them in photoshop,.

can figure out how to stack each channel in DSS, not sure how to combine them in Photoshop, I have CS2 if that helps

Leigh

[ChrisLX200]

so I stack the red green and blue images seperatly, then combine them in photoshop,.

can figure out how to stack each channel in DSS, not sure how to combine them in Photoshop, I have CS2 if that helps

Leigh

Doing it manually in Photoshop is a bit involved but there are plenty of tutorials on the web. Personally, I like Annie's Photoshop Actions which automate the process: http://morrisastronomy.blogspot.co.uk/2010/02/annies-astro-actions-version-20.html

ChrisH

[hazegood]

worked out t get the images combined in photoshop, but when I do, in the resulting image I see stars are not lined up, as am seeing duplicates ne in red and one in green, if that makes any sense

Leigh

[ChrisLX200]

worked out t get the images combined in photoshop, but when I do, in the resulting image I see stars are not lined up, as am seeing duplicates ne in red and one in green, if that makes any sense

Leigh

Yes, one the steps prior to combining the LRGB (after stacking each channel) is to 'Register' the greyscale images with each other so they all line up. Again, you need some software to achieve this step. Personally I use AstroArt 5, but PixInsight will do it and a number of other programs. Whilst you can try to shuffle them around in Photoshop often there is an element of rotation between them (not much, but it's there) and that is more difficult to deal with manually.

I've offered these data sets to folk wanting to try their hand at post-processing some typical astro images - but you do need post-processing software to do it. Photoshop is not a dedicated astro image processing tool but, if you know what you're doing, then you can use it for that and the 'actions' I listed earlier help a great deal. Far better though, is to use a program designed for the job - and even then there is a learning process to go through. To start from scratch without such software, well unless you're some sort of Wizard with Photoshop it is asking a lot I'm afraid.

ChrisH

[hazegood]

I have DSS, CS2, Gimp. neb3, Rigistax, and DXO7

can I make this work in any of those?