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lovesmexico615
10-09-2007, 13:40
Hey, I'm looking for a little information about tweaking my photos with Photoshop. I haven't bought an underwater housing for my Olympus 770SW yet, so I don't have a red filter for it. What it the best way to go about adding red to a photo without making the shot look too dark? I've tried reducing the blues, but everything looks too yellow. I've tried the auto-levels as had been suggested to me, but I get red pixels everywhere.
I'm getting fairly frustrated trying to adjust the photos, and need some advice!!

TIA!
Amanda

Kingpatzer
10-09-2007, 13:45
The best method is to carry a neutral grey card with you, and take a shot of that card either immediately before or after the pic you're interested in correcting.

They make water-proof ones.

Then getting the color adjustment is trivially easy as all you have to do is set that card to be 18% grey in the shot.

Without a grey card, the next best thing is to try and frame something pure white in the picture -- such as a bit of coral in the sunlight or a highlight on a fish. This isn't as good as a neutral card, but can work well enough.

Without either of those options, you're left playing with controls . . . which can produce good results, but is much more hit and miss, and frankly, every shot will be different (there's a reason why there's so many controls to play with after all).

torrey
10-09-2007, 14:10
I posted this in another thread before, but figured I'd just paste it here too for easier reference. I'm not sure about other photoshop versions, but here are the steps to whitebalance correction for Photoshop 7. I suggest putting these into a macro so you can just make 1 click and be done. If your pictures come out too red, play with the value in step 8.

1. Create 3 duplicate layers (layer / duplicate layer / okay)
2. Activate middle duplicate layer
3. Fill middle duplicate layer with 50% gray (edit / fill / 50% gray, 100% opacity, normal)
4. Activate top duplicate layer
5. Change blending mode to ‘luminosity’ (layer / layer style / blending options / blend mode / luminosity)
6. Merge top layer down into middle layer (layer / merge down)
7. Create new fill layer above merged layer (layer / new fill layer / solid color, group with previous layer)
8. Fill layer with red=255, green=0, blue=0
9. Change fill layer blending mode to ‘multiply’ (layer / layer style / blending options / blend mode / multiply)
10. Merge fill layer down into previous merge layer (layer / merge down)<
11. Change blending mode to ‘screen’ (layer / layer style / blending options / blend mode / screen)
12. Merge this layer down into first duplicate layer (layer / merge down)
13. Run auto-levels or adjust manually (image / adjustments / auto levels)
14. Adjust hue and saturation (image / adjust / hue-saturation)
15. Adjust color balance (image / adjust / color balance)
16. Adjust sharpness (filter / sharpen / unsharp mask)
17. Flatten layers (layer / flatten image)

rje634
10-09-2007, 14:38
Here is a thread from another board that has a pretty good tutorial on color correction using Photoshop.
http://www.scubaboard.com/forums/darkroom-tutorials/167033-cayman-diver-advance-color-correction-tutorial.html

Also you can search the web for the Mandrake macro somone made up.

diversteve
10-09-2007, 18:13
I have the color correct red action, the backscatter reduction action and the bring back the reds filter for Photoshop. PM your e-mail address if you want them.

somewhereinla
10-09-2007, 20:29
Well there isn't a formula that work for all situation. your pict has 3 channel RGB (RED, GREEN, BLUE) the channel you loose 1st is the red. If you loose the red channel completely, there is not much you can do, you can't bring back what's not there to beggin with. The best thing you can do is take a white balance reading at depth which has a similar effect as adding a red filter.

lovesmexico615
10-09-2007, 22:38
Thanks! Looks like I have tons of new tricks to try out. Now if I can figure out how to make a Macro...

diversteve
10-10-2007, 00:17
Thanks! Looks like I have tons of new tricks to try out. Now if I can figure out how to make a Macro...

Once you have it dialed in, just record it as an Action - the how-to is in PS help..

Basically you just hit record in the actions menu and run through the steps. Then you can save and apply the action across any series of photos.

You can also do simpler things like resizing/changing resolution of a group of photos using your own action. I do that a lot.

bversteegh
10-10-2007, 02:13
Does your camera shoot Raw? you can then adjust white balance after the dive with no loss of information. Just click the eyedropper tool on a spot that should be white - try a few different spots on the scene until you find one you like.

One caveat - there has to be some information in the red channel to work with - no recovery if the info isn't there.

lovesmexico615
10-10-2007, 19:37
Got It! Thanks so much, the corrected photos look great. I can't figure out how to embed a photo... and I keep getting an error when I try to attach a thumbnail. Oh well.. I'll figure it out.

rach
11-27-2007, 14:49
wow, great advice!! i'm going to try this on my next outing!

robcomptec
02-29-2008, 14:46
I posted this in another thread before, but figured I'd just paste it here too for easier reference. I'm not sure about other photoshop versions, but here are the steps to whitebalance correction for Photoshop 7. I suggest putting these into a macro so you can just make 1 click and be done. If your pictures come out too red, play with the value in step 8.

1. Create 3 duplicate layers (layer / duplicate layer / okay)
2. Activate middle duplicate layer
3. Fill middle duplicate layer with 50% gray (edit / fill / 50% gray, 100% opacity, normal)
4. Activate top duplicate layer
5. Change blending mode to ‘luminosity’ (layer / layer style / blending options / blend mode / luminosity)
6. Merge top layer down into middle layer (layer / merge down)
7. Create new fill layer above merged layer (layer / new fill layer / solid color, group with previous layer)
8. Fill layer with red=255, green=0, blue=0
9. Change fill layer blending mode to ‘multiply’ (layer / layer style / blending options / blend mode / multiply)
10. Merge fill layer down into previous merge layer (layer / merge down)<
11. Change blending mode to ‘screen’ (layer / layer style / blending options / blend mode / screen)
12. Merge this layer down into first duplicate layer (layer / merge down)
13. Run auto-levels or adjust manually (image / adjustments / auto levels)
14. Adjust hue and saturation (image / adjust / hue-saturation)
15. Adjust color balance (image / adjust / color balance)
16. Adjust sharpness (filter / sharpen / unsharp mask)
17. Flatten layers (layer / flatten image)

I'll check this out with some of my deeper photo pictures!

CompuDude
02-29-2008, 15:02
Just use the Mandrake action. Some pictures look terrible after it, so just un-do and get to work manually, but occasionally it can really work some serious magic.

Adjusting Photos in Photoshop 7.0 (http://pt010.da-kine.info/adjustments.htm)

Says PS7 but can still be used through CS3 no problems so far.

robcomptec
02-29-2008, 16:44
Just use the Mandrake action. Some pictures look terrible after it, so just un-do and get to work manually, but occasionally it can really work some serious magic.

Adjusting Photos in Photoshop 7.0 (http://pt010.da-kine.info/adjustments.htm)

Says PS7 but can still be used through CS3 no problems so far.

Thanks!

I'll check it out later...
(The picture example look VERY promising)