Reply to thread

If you want to adjust the left half of the image to match the green color cast on the right, here's one way.

• Temporarily open a Black & White adjustment layer.
• Go to Window>Info to open the Info panel, which allows you to hover your mouse over any part of the image and get a precise read-out of the RGB value of that spot.
• Find an area on the hull of each boat that has the same (or nearly the same) luminosity. Use the color sampler tool to mark those two spots, as I did below where the red arrows are pointing. The spots I selected have an RGB luminosity of 189 on the left and 190 on the right, which is close enough.

[ATTACH=full]149023[/ATTACH]

• Discard the B&W adjustment layer, and the Info panel will now display the actual color read-outs for points 1 and 2. The goal is to change the RGB value of point #1 to match the individual red, green and blue values of point #2, using a Curves adjustment layer.
• If you don't know how to do this, I've attached a tutorial here. Once done, you can use the mask in the curves adjustment so that the change affects only the left half of the image. (Personally, I would use the gradient tool to smoothly mask the entire image from left to right.)

[MEDIA=youtube]gwAFvd69ikI[/MEDIA]

Another Way

That said, I believe a better way to deal with color casts is to set the black, white and gray points and then make further adjustments based on clues from the image. Here's one approach:

• Open a Curves adjustment layer. The histogram shows that the image is washed-out with no dark pixels present. Move the black slider to the right, as shown here, to bring back the dark values of the image.

[ATTACH=full]149028[/ATTACH]

• Now set the Gray point, which is often a good way to deal with color casts.
• If you don't know how to identify the Gray point, here's a tutorial. (Note, for setting the Gray point, a Curves or Levels adjustment layer are equally interchangable.)
• My gray point is on the hull on the left where the red arrow is pointing. Use the Gray eyedropper in the Curves adjustment to set the gray point, which gives you this.
• To me, the left half of the image now looks natural, but the right half possibly still needs work.

[ATTACH=full]149030[/ATTACH]

[MEDIA=youtube]6l4EplCecbM[/MEDIA]

• On the right side of the image, it seems likely that the "No Diving" sign should have white text. But if you hover over the white areas of that sign using the Info panel, the RGB values are not identical and are particularly deficient in the blue channel.
• Similar to what you did above, select a spot of that text using the color sampler tool, open a Curves adjustment, and set the text to a neutral color with RGB values of roughly 200, 200, 200.
• Apply a right-to-left gradient in the layer mask so that this new curves adjustment affects only the right half of the image and smoothly fades away as we move to the left.
• Lastly, I boosted the overall saturation of the image to arrive at this final result.

[ATTACH=full]149034[/ATTACH]