Color correcting no-flashl digital pics

[Gilligan]

ssra30 mentioned on a previous post seeing this process by "mandrake" on digitaldiver.net
The process is for correcting digital photos taken without a flash. I posted a photo of a patch reef on that previous post mentioned above using a diffrent process. I have posted 4 photos on this link to demonstrate the use of "mandrake's" technique, one photo I took using auto white balance and one I took using manual white balance from a dive slate.

"mandrake's" process is using Photoshop Elements and I used Photoshop 7:
1) create 3 duplicate layers of the original photo.
2) Make the middle duplicate layer active and fill it with 50% gray (Edit->Fill->50% Gray, 100% opacity, normal)
3) Make the top duplicate layer active and change its blending mode to 'Luminosity'. Merge it down into the middle (gray) layer. You now have a b/w image of your original photo in this layer.
4) Create a new fill layer above this b/w image (Layer->New Fill Layer->Solid Color). Check 'Group with Previous Layer'. Fill this layer with red (R: 255, G: 0, B: 0). Change this layer's blending mode to 'Multiply', and then merge it down into the previous layer (the b/w image). You've now got a funky red photo.
5) Change the blending mode of the funky red photo to 'Screen' and merge it down into the first duplicate layer. You've now got your original image with a much nicer red.
Now run auto-levels, which actually works now, make the midtones a little brighter (move the midtone slider a little to the left), and sharpen.

[ssra30]

I think this is a really cool process. It also works very well for a picture with flash when the flash is not set properly,misaimed etc.
Occasionally it would add a bit too much red especially when the flash is used. In that case I just turn down the opacity for the final merge between the original and the funky red pic and that works really well too.

[khel]

Thanks for the info, cannot wait to try it out

khel

[Meddler]

You can perform the same trick using Gimp.

1. Open Layers->Layers Channels & Paths
2. Click on the duplicate layer button and make it active (and make the original image invisible)
3. Add a new layer with a forground colour of grey #808080
4. Set the layer mode to "colour " to get your grey image
5. Merge the grey layer and the duplicate layer
6. Add a new layer with a foreground colour of red #ff0000
7. Set the layer mode to multiply and merge your grey image with the red.
8. Set the red image mode to "screen" and make the original
image visible. If you get a purple colour cast, fiddle with the transparency of the red image until it looks about right.

I have to say its quite a nice technique and is rather good at restoring the fleshtones of your buddies. Im not sure that I like the way it makes the water disapear, but I guess you can fiddle with it to get the right amount of blue.

[khel]

Meddler once bubbled...
You can perform the same trick using Gimp.

Are you using Gimp in Linux?? and if so, do you know, by any chance any good programs for working with RAW format??

khel

[mandrake]

Hi, I'm mandrake from the digital diver forum. Just wanted to say how honored I am that you're using a technique of mine (merging a b/w image projected with red back into the original image). I also wanted to point out a few things I consider important:

1) My idea came from reading (and extensively playing with) the chapter on color separations in the book 'The Hidden Power of PhotoShop Elements 2' by Richard Lynch. This book is an absolute must-read for anyone really into photo-editing. You'll benefit from it if you have PS Elements or the full PS, though you'll get most benefit out of it with PS Elements. It includes a CD toolset to give Elements many tools that exist in the full PS, like curves.

2) My technique is only a shortcut version of what I would really do, which is a full color separation and examination of the three layers (as described in the book, and automated through the 'split RGB with preview' tool). I would also create at least 2 and possibly as many as 4 different b/w images (there are several different options) and see which one worked best, whether as a replacement of the red tone layer or as a supplement to it.

The four different b/w images I consider for use are:
a) original image as luminosity layer merged back into 50% gray layer
b) desaturated image
c) the green tone from the original image
d) the blue tone from the original image

In general I find that either a) or c) is best, and d) is worst.

3) After you've put the red into your picture, you often have to take some of it back out again. I use the hue/saturation tool and make either a change of about -20 to -30 on the master hue, or else play with individual colors or make selections with the eyedropper tools. I consider this an essential step that goes hand-in-hand with adding the red back in. You must do something like this to turn your water blue again.

4) After all this is done, it still doesn't hurt to try auto-levels, auto-color correction, or if you have PS Elements, the color cast tool, or any other color-balancing tool or scheme you have, just as sanity checks.

Again, thanks for the tribute. But don't turn it into a formula. Every photo is different. I tend to get in a rut with these things, and forget to try simpler things sometimes. On a couple of photos recently I found that, after going through my 20 usual steps, that just an 'auto-levels' in a separate layer, with an opacity of somewhere less than 100%, was better than anything I could do.

I've also stumbled across a great technique called 'contrast masking' recently. Here's a pointer to the site I found it on, which also contains pointers to other places:

http://www.normankoren.com/PWP_contrast_masking.html

I can't believe how wonderfully this enhances many of my photos. Hope you like it. Read the 'Contrast Masking with PhotoShop' section -- I haven't bothered with anything after that.

If you'd like to check out my image galleries, try:

http://www.pbase.com/dkusner

[No Fish]

I tried it and just can't quit. I am using PS 6. This technique is amazing. Thanks Mandrake and Gilligan. Now...Back to those blue-green photos...........

[James connell]

here's the job setup as a loadable action.

i'm working on a fix to auto adjust the amount red put in - mandrake's right , it needs tweeking. still a good fix.

after the action is run you still need to tweek the red channle a little and sharpen.

[khel]

No Fish once bubbled...
I tried it and just can't quit. I am using PS 6. This technique is amazing. Thanks Mandrake and Gilligan. Now...Back to those blue-green photos...........

Same here, I've been playing with it all the evening - it's GREAT!! I just cannot believe, that I didn't use it before (shame on me as a former graphics designer)

Thanks a lot guys!!

khel

[Dee]

Glad you found our pond! I've printed your technique and plan to play with it this weekend.