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westsky
05-04-2005, 09:10 PM
Recently we talked about making files availible so people could have a try at image processing.
I have uploaded a image file of NGC 5189.
file is zipped and is 144kb, unzipped size is around 900kb.it is in BMP format so should be able to be viewed by most if not all image processing software.
here is the address
http://members.iinet.net.au/~westsky/NGC5189.zip
The image is 50 images x 30secs
taken with a C11 at f6.3
Go ahead and have a go and let us see what your results are like.
cheers
David.

[1ponders]
05-04-2005, 10:55 PM
Ok here's my first try. Lost some of the outer diffusion of the neb but not too shabby for five minutes worth.

janoskiss
06-04-2005, 12:19 AM
I gave it a go but couldn't do any better than you Paul.

iceman
06-04-2005, 12:43 PM
Nice job Paul, better than my effort.

[1ponders]
06-04-2005, 12:59 PM
Mike, in PS after you've mucked around with the levels and colour curves a bit, try outlining the nebula with the lasso (lightish feather20 - 30ish), invert the selection, reset the black point using levels, invert the selection again and try a very light (0.7 pixel) gaussian blur, then muck around with the individual colour curves or visa versa (ie curves then blur). Then deselect.

I'll have another serious go tonight with some masking.

Cheers
Paul

westsky
06-04-2005, 04:41 PM
Paul very nice, better than I have been able to do so far.
Ice yours is better than mine also.

David

Mombat
06-04-2005, 07:30 PM
I've never tried this before so how do i get the images into registax once i've down loaded
Any help would be appreciated

Thanks Richard

[1ponders]
06-04-2005, 07:48 PM
If you're going to try it in Registax first for waveletting and colour adjustment then go "Select" - (navigate to the folder the bmp is stored in) - "Files of Type" choose bmp - then open. Registax will then go straight to the waveletting page.

Have fun

Mombat
06-04-2005, 08:02 PM
OK thanks i'll try that

janoskiss
06-04-2005, 11:41 PM
Had another go tonight. For sake of realism, I kept all processing operations global (applied to entire image). The two more unusual things I've used:

1) GIMP's convolution matrix to manually shift the red component up by 1.2 pixels,

2) the "Dilate" filter to highlight the structure of the nebula. The joining of the two close stars in the nebula is an undesired artefact of this filter.

Rest is just several level tweaks and Gaussian blurs.

http://members.optusnet.com.au/~janosk/misc/5189-1.png

ballaratdragons
07-04-2005, 02:15 AM
I gave it a go in PaintShop Pro but it just made it worse and I didn't want to cheat by airbrushing it so I pinched one from Google.

Do I win?

westsky
07-04-2005, 06:47 PM
Janos, I might have to give Gimp a try for image processing, it looks like you added a luminance layer, very nice.

David.

westsky
07-04-2005, 06:49 PM
Hey Ken there's no such thing as cheating in image processing, whatever you can do to make the image good is what counts,
by the way the prize is sitting in the middle of 5189 you have to go pick it up :-))

David.

janoskiss
07-04-2005, 08:52 PM
If you manage to make friends with the quirky interface (not nearly as quirky since v. 2.0), the Gimp is really a joy to use. I have limited experience with Photoshop but when I do use it I "think in Gimp". They seem very similar in terms of capability. On a technical note: with the GIMP you are limited to 8 bits per colour, in P-Shop to 16bits. There is a Gimp-on-steroids called CinePaint that is used by some Hollywood studios. It supports 32 bits per colour. And it's as free as the Gimp.

ballaratdragons
07-04-2005, 11:14 PM
O.K. I gave it a go in PaintShop Pro 4. I don't like the outcome!

From the original I raised the Brightness and contrast to find the Nebulous gas then highlighted all the gas. Then I highlighted the stars and added a smidge of the right colour to them. When finished I brought the brightness down to -20 and the contrast back down to 0. I think it looks terrible but it was fun trying.

janoskiss
07-04-2005, 11:37 PM
Ken, At least you got the goat! I think I got a camel... :confuse3:

Yours: http://members.optusnet.com.au/~janosk/misc/goat.png Mine: http://members.optusnet.com.au/~janosk/misc/nogoat.png

ballaratdragons
07-04-2005, 11:43 PM
Is there a goat in there? I just highlighted the gas! The centre looks like a calamari ring to me!!