Photo Restoration - - Removing Yellow Blotches in Restoration

Foxkatt · #1 01-22-2006, 08:20 PM

Hi all,
This is my first post.

I certainly hope that you kind experts out there can help. I've gone through my entire library of Photoshop books and nothing I've tried has had more than limited success. I am restoring some photos to use in an iMovie presentation. Since there are approximately 125 of these, I need to work fast so the two or three which are like the one posted here are of special concern to me.

These pictures went through a tornado and have yellow blotches across the surface. I've checked the channels and most of the damage is in the blue channel with a tiny bit in the red channel. (Using PhotoshopCS) Now I've tried taking a second file, changing it to LAB mode and copying the lightness channel to the blue channel in the "original." That gets rid of most of the damage although the color goes "off." If I also replace the red channel, the color is really off and my experience with curves is not the best so far and I've been unable to get a good looking color back. If I leave just the blue channel changed, I can get an approximate color that looks ok but there are reddish blotches in the background.

I just know there's got to be a way to get rid of these other than the time-consuming labor of the healing brush and patch. As I said though, I've not been able to find it in my books. Anyone got any good ideas? Your help and comments will be MUCH appreciated.
thanks,
Foxkatt

Swampy · #2 01-22-2006, 08:32 PM

If all your pictures have the same yellow tinge, it should be easy enough to fix.

1. Converted to LAB color and copied the Lightness channel
2. Back to RGB and pasted the LAB lightness channel into the RGB Blue channel.
3 Curves adjustment layer to raise the blue channel.

Foxkatt · #3 01-22-2006, 08:45 PM

I guess it's the curves adjustment layer to raise the blue channel that I'm having trouble figuring out. Haven't done that before and am not getting good results. Also, did that leave the reddish blotches still in the photo?
Would I then do the same thing with the red channel after getting good color in the blue?
Sorry to be so dense.
Foxkatt

mistermonday · #4 01-22-2006, 09:13 PM

Foxkatt, if the rest of you stains are not much worse than this image, then you may find this method slightly faster. By all means move the image into LAB. But select the B channel and apply a Gaussian Blur. Dan1 needed 30 pixels, but you should apply just enough blur to get rid of the light areas which should not be there. You can now convert back to RGB and stop there. Or you can do a color adjustment using the curves in LAB or take the image back to RGB and apply curves or Hue/Saturation which will work very quickly. One last point, on some of these images, some of the damage will still be present in the L Channel when you convert to LAB. This can be selectively blurred in te L channel using the Blur brush. Good luck with your restorations. Oh BTW, welcome to RP.
Regards, Murray

mistermonday · #5 01-22-2006, 09:44 PM

Foxkatt, one other thing I just noticed is the line across her head which is predominantly red and shows up in the A channel when you convert to LAB. Again it takes two seconds to fix. Just select the A channel and apply a gaussian blur. This time it only takes 4 pixels to obliterate the line. After looking at the result after the two LAB channel blurs, it appears that the fatest way for you to shift the color would be Ctrl M to bing up the curve dialog, then click on dead center of the A channel and just raise it a bit until it looks good. Regards, Murray

Foxkatt · #6 01-22-2006, 09:51 PM

Thanks SO much. The LAB stuff especially helped. I can do that quickly and just did a bit on the attached pic. It's much better already.
I'll try it again with the second blur in the A channel. This is just the type of technique I was needing.
Thank you, thank you, thank you, thank you......
Foxkatt