help w/ this image: removing color cast

[ylwdog]

I photographed a dog hunt test today. During one of the shots I got this black Labrador and there is a green blur from the grass over his paw and leg, and then the grass and ground is discolored in the same area.

I got decent results w/ the clone stamp tool using the "color" mode, but it was not good enough for printing. But I am wondering if there is a better method w/ other tools to fix that area over the dog's right front paw and ground.

Thanks,

Doug

[mistermonday]

Doug, there are many ways to get rid of the green. One quick and simple way is a Hue/Saturation Adjustment Layer.
Regards, Murray

[ylwdog]

Hi Murray,
That looks decent. The problems I typically have is the blending of detail when altering an image when the adjacent cells contain harder lines.
In this method you used did you simply select the offending area and begin altering it, or was there more to it, i.e. feathering or some other combined tools/technique?

Thanks for the help,

Doug

[Swampy]

Try my "Blur away the color cast" tutorial as a start. Link to my PS tutorials in my signature.

[chillin]

In addition to Murray's "Hue/Saturation Adjustment Layer" I would use some curves/levels adjustments.

[htown]

targeted yellows in Hue/Sat layer with a mask thena little cloning.

[unimatrix001]

used rectangle selection tool selected the green area on the dogs foot. selected black from around the area of the green cast. used the paint brush in color mode to remove green cast. used a levels adjustment to correct the highlights in that area. used the burn tool to finish up.

[daitri]

played about with white balance ,hue sat,contrast.

[mistermonday]

Doug, a simple Hue/Sat layer can take care of the whole problem without burning or selctions or color range selections. You can follow this process with the screenshots attached.

1. At the bottom of your Layers Palette, click on the add adjustment layer button and select Hue / Saturation. From the pull down menu (master is default), select the Green channel. Look at the rainbow sliders at the bottom of the window (circled in Red) where the Green hues are shown between two split triangles. Drag these two triangles toward each other until the meet (touch) preferably around the center of the space between them.
Now drag the Saturation slider all the way to the left to the end. Finally select the eyedropper with the plus sign. The result should look like Screenshot2 below.

2. Move your eyedropper over the dogs legs. Click on an area that is green and you will see it turn gray/black. Click on another area that is green and more will turn gray/black. Keep doing this on both legs until all of the green is gone. This may take you anywhere between 1 and 5 clicks. The rest of the photo will be affected but do not wory about that for the moment.
You will notice that some of the areas where the green contamination was are now gray instead of black. That's because the green was also lighter. So to fix this, just drag the Lightness slider to the left. I pulled it back to -80.
The result can be seen in Screenshot3.
When the legs look ok to you click OK.

3. Now we need to quickly fix all the rest of the image whose color was adversely affected by the adjustment layer. This will be easier than it looks.
At this point you will notice a white square or layer mask on the Hue/Sat layer. We want to invert it to make it black. It should automatically be active so just press Ctrl+I to invert it. If for some reason it is not active, just click on the white square and hit Ctrl+I. You will now see that the image has returned to its original start - green cast and all. No problem.
Hit the D key to reset the Foreground/Background color swatches in the tool palette to Black & White. Make sure White is the foreground color (if not hit the X key to toggle it). Now select you Brush tool, set the hardness to about 25% and paint over both of the dog's legs. If you accidentally overshoot onto the background, just hit the X key and paint over the spill with black to fix it.
It should take you about 30 seconds to paint the adjustment back in. The whole process should only take you about 2 minutes once you go through it.
The result is Screenshot4.

I hope this helps.
Regards, Murray

[ylwdog]

Good Day Murray:
That was a fantastic way to handle the problem, thank you!
If I may, would you be able to explain to me what each step did so that I may understand better what is happening, e.g. "Drag these two triangles toward each other until the meet (touch) preferably around the center of the space between them", is this for the purpose of reducing the spectrum of green that will be working with in this step?
If you do not mind explain the reason behind the method I would also like to ask a few more detailed questions during your explanation.

Again, thank you sincerely

Doug

[mistermonday]

Doug, you are welcome.
I hope the following example will help better explain the process.
Attachment 1 is a photo of Prince Harry having a bit of a bad skin day. On the surfact this may look like a challenge because there is red in his hair and there is red in his face and lots of strong red in his cheeks plus that lone big red splotch on his forehead. Some of Photoshops tools will pose a challenge when trying to select and fix the anomalous areas. So let's use the Hue/Sat adjustment layer.

1. Add a Hue/Sat adj layer and select the Red channel. Drag the Saturation slider to the far left. Notice that the whole image is affected (no screenshot, but try it). Adjusting the Hue and Sat levels will impact the whole image and not get us to where we need to be. So what we need to do is the same as with the Dog photo. This time select the Red channel and drag those triangles together. Drag the Sat slider all the way to the left. If ou see any gray in the image just nudge the merged triangles over a little to the left or right until the gray completely disappears.
Now once again slect the + eyedropper and touch the redest part of Harry's cheeks and the bright red in his ear. After 2 or 3 clicks you should end up with screenshot 1 attached. (Dragging the saturation slider to the left just provides us with a visual guide so we can see what pixels are affected by the eyedropper.
Closing the triangles basically reduces the starting slection range to 0. So there are really no reds selected until you do so with the eyedropper. Moreover you are controlling the selection to a very tight range and so you are tightly controlling the colors that you will finally adjust.
BTW, the lips will lose color but don't worry about that for now.

2. OK, now you have isolated the strong red. Move the saturation slider back to the center (0). Drag the Hue slider toward th right to move the selected color from red toward yellow. I stopped at +12, but it is up to your taste. See screenshot 2.

3. This is where you usually click OK. However, I found that the image overall was a little too saturated. So I pulled down the channel window and selected the Master channel and lowered the saturation. See Screenshot 3. Now press OK.

4. When you are done, there may be an unavoidable casualty - the lips. Now we are going to fix it using a similar technique as we did last time with the layer mask. This image is different form the dog image in that we only need to fix the lips. So with the mask layer still active (and the square icon still white) take a black soft brush and paint over the lips- and your are done.

Are you are wondering why on the dog image we inverted the layer mask and painted with white? It really has to do with how much painting you want to do. With the dog image a lot of green everywhere else in the image was affected by the Hue Sat adj layer. Rather than painting it all black, it was faster to invert the mask, and just paint the legs with a white brush. For this image everything is ok except for the lips. So leave the mask white and just mask over the lips.

[MiningArt]

Thanks for the detailed explanations in this post.

[BobZZZ]

I used brute force. Duplicate layer make rough rectangular selection of green flare. ctl m to bring up curves Click a point on the green bit of the dogs leg to fix a point in each channel. The dogs foot is around 60 in RG&B so lift each point to get that sort of reading and jiggle till leg looks ok.

Then ctl d to deselect add layer mask paint white with soft brush 30% to reveal.

Still a bit low on contrast so dup top layer set to multiply and adjust opacity.

Last off the entire image has a green cast to my mind so curves adjustment layer on top and lighten the green channel a touch.