PDA

View Full Version here: : Make your own RGB of my Rho/Antares shot


montewilson
06-06-2007, 12:37 PM
Guys - Here are the three colours of the Rho/Antares I posted a few days ago.

Have a go at putting together an RGB composite of the shot. Play with the colours, levels and contrast. See what you can come up with.

I wont be upset if someone can come up with a better version of the shot than mine, I am only just getted started in the caper.

Have fun.

All files are about 550k.

http://astronomy.proem.com.au/rho_red_640.tif
http://astronomy.proem.com.au/rho_green_640.tif
http://astronomy.proem.com.au/rho_blue_640.tif

Bassnut
06-06-2007, 02:01 PM
Hi Monte

I had a tweak, eeek :P

Fred

Bassnut
06-06-2007, 02:28 PM
Hi Monte

Nah, on second thoughts, your processing is much better :D

Fred

RB
06-06-2007, 02:43 PM
For some reason I can't download these tiff files.
Any chance you can upload all three into a zip file somewhere (even here on the IIS server) Monte.
I'd love to have a go !

:thumbsup:

Bassnut
06-06-2007, 02:55 PM
Hi Andrew

I found the same thing just clicking on them. Right click and save target as, that works.

Fred

Garyh
06-06-2007, 03:01 PM
Hi Monte, I have no idea at what I am doing...but this is what I ended up with..:). It`s more involved than doing my canon shots!!
cheers Gary

RB
06-06-2007, 03:36 PM
Thank you so much Fred.

:thumbsup: :thumbsup: :thumbsup:

Dr Nick
06-06-2007, 04:16 PM
Wow! They are some amazing images! ;)

montewilson
06-06-2007, 04:23 PM
Fred - why is your image size bigger than the orginal? Keep it at the normal size and you should have a better result. As it is you have done well on the colours.

As for the rest of you - well done!

Bassnut
06-06-2007, 05:32 PM
Monte

I doubled the size as soon as I downloaded it, its a nervous automatic reaction us pixel-challenged plebs (mine cam is 1.5MP) have to subs in a vain attempt to increase res. Processing larger tends to unpixalate images. You wouldnt know about this, you wouldnt need to even come close to that sort mucking around hehe.

I found the res on your subs you posted a bit small to get really fancy, so I gave up ;-(.

Sheesh, the colour is very mute, I cheated to get it up, no wonder you over-curved to push up the colour that was there.

I think its a difficult pic to process to do it justice generally.

Fred

RB
06-06-2007, 06:29 PM
You've captured very nice data Monte.
This has lost a bit of colour depth when compressed for the web but I could only imagine what it would be like processing with the full res frames.

:thumbsup:

Ric
06-06-2007, 08:10 PM
Hi Monte, thanks for the opportunity to have a play with your data. I had a quick play in Maxim and came up with this. hope I've done it justice.

Cheers

Phil
06-06-2007, 08:17 PM
O.K hear is my go thanks for letting as play around with this great image.
Phil

Ric
06-06-2007, 08:26 PM
It's amazing to to see all the variations that members are coming up with. there are a lot of varied interpretations and they all look great.

Cheers

sheeny
06-06-2007, 08:30 PM
This is an interesting thread! Very interesting to see such different results from the same data! Obviously lots of scope for creativity.

Al.

erick
06-06-2007, 09:25 PM
Looks like everyone is enjoying this. Perhaps this could be a regular - someone posts raw data and all you data tweakers give it your best shot - then we vote? Could be a lot of learning as people describe the techniques they use?? :confuse3:

montewilson
06-06-2007, 09:38 PM
Great idea, I for one will have a fairly constant flow of RGB's but there will be others.

avandonk
06-06-2007, 09:44 PM
Here is my go at it Monte. I used EasyHDR to compress the dynamic range.

Bert

okiscopey
06-06-2007, 10:51 PM
Fascinating idea! Never processed an astro image before so had fun. Only have Photoshop so had to work out what to do with the layers.

It's amazing how different everyone's results are - I've made a composite of those done so far - it's only a posting-size image but can make higher res available if someone tells me how to do it.

My mediocre result is the one on the top right - I tried to increase saturation but started losing image data. Obviously dedicated astro s/ware is the way to go.

montewilson
06-06-2007, 11:25 PM
Guys ! Can someone please grab my original image and include it in the mosaic? I don't have image processing software on this computer.

http://astronomy.proem.com.au/rho_colour_small.jpg

erick
06-06-2007, 11:36 PM
ps. and flip Garyh's vertically :)

jase
06-06-2007, 11:47 PM
This is generally a difficult area to process. Quite a vast dynamic range and colour complexity. The orange/yellow hues are difficult to obtain well. I'm not too certain the correct color balance on the Astrodon’s. They are not exactly a 1:1:1 ratio, but close. You still need to take into consideration the blue extinction factor as well.
I settled on a R:G:B of 1:1:0.8 for the final RGB combine.
As red and green make yellow, this emphasises the orange/yellow hues. I only used 20% saturation. Could have gone higher, but lacking sufficient data would result in more noise. I used the R channel with minor sharpening applied, this was then layered onto the RGB image with 80% opacity. RGB was Gaussian blurred (very mild). I've clipped in green and blue which I expected as I should have raised other colour levels instead. Getting rid of the green halo around Antares was a pain. I used the colour selection tool then dropped the green channel using curves - this needs more work in particular greater feathering.

This is a good example of what the area is suppose to look like with good colour balance and processing - http://www.starryscapes.com/nebula/rho_ophiuchus.html

okiscopey
07-06-2007, 12:54 AM
Composite .. latest edition!

iceman
07-06-2007, 06:19 AM
Beautiful result, Jase!

Ingo
07-06-2007, 07:44 AM
Where does the red green and blue come from? I put them in photoshop, layed them on top of eachother, and there were no colors?

:lol:

montewilson
07-06-2007, 07:49 AM
Have you converted the red to RGB from Gray scale before adding the other colours?

That is very important.

avandonk
07-06-2007, 08:06 AM
I think that all need to be flipped as they are the mirror image. Here is one I did in late March.
Large version here 1.5MB
http://members.optusnet.com.au/~trlee8/rho_oph.jpg

Thread here
http://www.iceinspace.com.au/forum/showthread.php?t=18680

You can see my version lacks the delicate detail in Monte's data due to different optics . But it shows more dynamic range.
I think if Monte tried series of exposures each time doubling the exposure time EasyHDR would then get all the dynamic range of this region. It is a difficult region to image.
I would be interested to have a go at a set of RGB's taken this way.

Bert

RB
07-06-2007, 08:50 AM
This is a great idea for a thread Monte, thanks for the oppertunity to try our hand at RGB processing.
I had another go at it too.

Maybe you can upload the full res set of frames onto the IIS server (ask Mike).

Great capture and thanks again !

okiscopey
07-06-2007, 10:06 AM
Ingo, the way I did it (which might be the long way round) is as follows:

Turn each of the JPEGs (which are 16-bit greyscale images) into RGB.

Note: I use Photoshop CS2 which handles 16-bit images, earlier versions handle these in varying ways … you may need to turn the originals into 8-bit greyscale and then into 8-bit RGB, thus losing a great deal of the tonal range.

For the blue one, add a new layer and fill it with solid blue R=000 G=000 B=255

Change the filled layer from ‘Normal’ to “Multiply’.

Flatten the image. You now have the ‘blue’ image.

Do a similar operation to the green and red images, using R=000 G=255 B=000 and R=255 G=000 B=000 respectively.

Copy and paste the green and red images onto the blue (background) image to give a three-layer file. (You can drag and drop between files, thus avoiding the clipboard, but then you may have alignment issues.)

Turn layer 1 (green) and layer 2 (red) from ‘Normal’ to ‘Difference’.

Voila … a vaguely-coloured image.

You can then muck about with the individual layers (saturation, etc.) to see what effect it has on the displayed image. I did this to at least make the ‘whites’ white. If you flatten the image, you can do the overall levels, saturation, etc.

Trouble is, it’s a lot of work to produce - at least in my case - a final image inferior to the astro processing s/ware used in the other posts (not to mention the knowledge and experience that goes into tweaking the red, green and blue images along the way).

I assume the result I obtained is more-or-less the best one can do using PhotoShop alone.

Bassnut
07-06-2007, 10:37 AM
Theres a much easier way as Monte infered.

In CS, convert the red image to RGB and simply copy and paste the green image into the green channel (as is, no RGB conversion) and the blue image into the blue channel. The red channel already has the red image from the 1st RGB conversion.

Now you can process each channel seperately or the RGB layer altogether, its already a "flat" single layer.

Fred

Garyh
07-06-2007, 11:49 AM
Thats similar to what I did, made new RGB image then pasted into the appropiate channels. Done some gamma corrections on the various channels etc, then the usual on the whole lot..
Very interesting experiment!!!! To see them all together and what everyone has done different to them...........:thumbsup:
Mine looks like its a bit on the blue side with color balance..
thanks Monte for the chance to have a fiddle...:lol:

Doug
07-06-2007, 12:23 PM
Either way is just as good...it comes down to personal preference. IMNSHO.

ving
07-06-2007, 01:03 PM
what a brilliant idea!

funny how everyones is different! :)

bloodhound31
07-06-2007, 02:29 PM
Great idea and awesome images peoples!

I have no idea how you do it, but I am impressed:thumbsup:

Baz:D

okiscopey
07-06-2007, 02:42 PM
I used to learn something new every day, now thanks to IIS I learn at least three new things every day!

I use PhotoShop a lot for general photographic work, but never knew you could copy/paste into one channel. I note the channel has to be selected for this to work (of course!), and if you have two channels selected the copied image is pasted into both.

Doug
08-06-2007, 11:53 AM
For the time being..............here is a tentative go.
Hope to have another go in a fortnight or so
Thanks Monte
Edit: the 1st image looks worse on the web than it did in PS2. second image is from before I became preocupied with getting Antaries to shine with its orange glory.

montewilson
08-06-2007, 01:24 PM
Guys - Thanx so much for all the replies. I am pleased to see there is such interest in putting together these images.

I, like a few others have commented am also surprised at how many variations there are. What is important to remember is that not one of them is wrong and also none are "correct". We can only speculate what it is really like.

I will have some more soon. I will see if I can put the full frame shots in tif on the FTP. They are not small files but I am sure they would provide plenty of entertainment.

The Astro Imaging Section of the ASNSW will be having it's Bi-monthly meeting on the 20th in Epping. Non members are welcomeand encouraged to come along too.

We will be taking some pictures with my TAK FSQ-106 and a digital SLR and processing them there on the night. Come along, bring a laptop if you have one and meet with other astro imagers in a relaxed event. If its cloudy we'll all sit around and shoot the breeze on AI matters. But seriously we will have plenty to do even if its cloudy.

Hope you can make it.