Matching colors from one side to the other from scan

[R.Braverman]

Not sure this is the correct place to start this, so BY ALL MEANS move it to where it should be if necessary (as if you needed my permission ...)

As you can see, this is, well maybe you can't ...
OK, this is a scanned in photo, if you look the boat on the left is/has a bluish cast, while the right one is "greenish" (is my ignorance starting to show ...?). I think it's a reflection in the lens when it was taken, but obviously I'm not sure - at least that's what it appears to be..
This was taken 50 years ago, I know the fellow who took it, and he would NOT have screwed this up.
So as I can pretty much mask that area, how do I try to blend it's colors to match the right side?
A brief explanation; as I think most people do, I learn what I need as I need it, and this is the first time I've run into this.

Thanks.

 

[Rich54]

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.

• 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.)

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.

• 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.

• 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.

 

[thebestcpu]

Hi @R.Braverman
I will explain my approach, yet the first thing I wanted to point out is that the blue areas on the left are not a simple gradient, and not sure why it is that shape that directed me in the approach I took. The image below is a Hue map of the entire image and you can see that there are specific areas that are way off in Hue compared to the others:



So, I first decided how I would want to fix the image's white point, so I only had to work by hand on the smaller blue area. So I made the image a Smart Ojbect, and then applied the Camera Raw filter using the white balance eye dropper on the ship's hull on the right. So here is your starting image:



After applying the white balance eyedropper on the right ship, here is the result:


Now, I added a blank Layer and set the blend mode to color to match up the left blue areas to the right. I sampled areas on the right to paint on the left blue regions. For this example, since you are just asking for directions, I applied a mask and only worked on the boards of the fence of the walkway, the walkway, and the box that I marked with a sample point. I sampled the color to paint on the right and then painted on the left side.
I saved the selection of where I was painting and used that as the mask on a curves adjustment Layer to change the luminosity to better match from left to right (this is optional). The resulting image is below for those selected areas where I was matching the color:



So, given the odd shape area with the blue tint, that is the general approach I would take.
I hope this gives you a direction to consider.
John Wheeler

 

[R.Braverman]

Wow your responses/suggestions/tutorials are AWESOME!
SERIOUSLY!

I knew the answer to my question was going to lead into this area, an area I've nimbly avoided in the 20 odd years of using PS occasionally, and at times, avidly.
I've printed out everything and need to to read and reread through, so that I can get more of an understanding of the concepts you both are speaking of, then, I hope, can more easily put them to use.

The more I see that "odd shaped" area of blue, I'm beginning to think, as it is a photo not a slide, that maybe early on a small spill of water? Definitely not a reflection of the sun off the lens.

I hope you'll not mind when I post back some more questions about this.

Again - AWESOME!

 

[thebestcpu]

You're welcome @R.Braverman
Feel free to ask more questions. I am often around and there are a large number of forum members willing to help.
As far as the odd shape, hard to know. The embedded CMY colors of photos do have a tendency to fade and can do so unevenly if depending on how they are stored and what is up against them. Given the sharp lines at some points, it almost made me think some other sharp edge element was placed up against it or maybe even tape. It is somewhat a moot point since the color shift is there, and restoration would be needed no matter the source of the problem.
John Wheeler

 

[R.Braverman]

Now, I added a blank Layer and set the blend mode to color to match up the left blue areas to the right. I sampled areas on the right to paint on the left blue regions. For this example, since you are just asking for directions, I applied a mask and only worked on the boards of the fence of the walkway, the walkway, and the box that I marked with a sample point. I sampled the color to paint on the right and then painted on the left side.
I saved the selection of where I was painting and used that as the mask on a curves adjustment Layer to change the luminosity to better match from left to right (this is optional). The resulting image is below for those selected areas where I was matching the color:

Ok, re-read and promptly came upon something I don't know/understand: could you explain this a deeper? I don't (and this shows my naivety) how to use the sample point, in regards to sampling 2-3 points. That's not really how I wanted to explain it, but the more I look at it, the less I can clarify. I can't figure out how to make it clearer. My mind does function to clearly anymore, as I'm sure you've figured out by the simple fact that the photo itself is close to 50 years old.
At any time there are pages, links, sites that explain stuff I ask about TELL ME! I've look for this, but can't really find what I think you're telling me.

 

[R.Braverman]

Feel free to ask more questions. I am often around and there are a large number of forum members willing to help.

Back in the early 90's I was involved in programming, feeding and caring for BBS systems, so I've been involved with "forums" and discourses for a while. A lot has changed, obviously, but ONE thing that hasn't, is I've noticed ESPECIALLY when dealing with Photoshop, almost more than any other S/W, the more advanced users are MORE than happy to help those of us who are new or non-avid users of the program, but want to learn.
I'm on another forum, whose name escapes me at the moment, and they are the same.
I just wanted to make sure that you two and any others I run into, that I'm deeply grateful for the help. These particular photo's are precious to me so it means a hell'ava lot.

 

[thebestcpu]

Hi @R.Braverman
I have noted your appreciation and appreciate it!

This first picture is after I set the white point on the boat of the right and we are ready to paint colors over the off-color left side.
Note that in the Layer Stack shown I have a blank Layer that is active and the Blend mode is set to color.

You use the Eye Dropper tool (shown by the right green arrow) to select a good color you want to paint over on the left side. In this case, I was sampling the wood color of the upper rail of the fence. Note that it is already sampled as the foreground color chip now shows the color of that fence board (left green arrow)



Now, you select the brush tool (which will use the foreground color chip) and paint over the top railing on the left side. In the image below, I use the green arrow to where the brush tool is where I have partially painted from right to left partially over the board and you see it has taken on the color sample from the right side.

Sometimes, it is helpful to make a selection around the areas you want to paint so as not to paint in places you don't wish to touch with that color.


.
You can continue that process, sampling on the right and painting on the left.
I hope that clarifies this step.

Also, note that the images were taken with my iPhone instead of a screen capture so the "tool" would clearly be shown. That is why there is a pattern in the image.
John Wheeler

John Wheeler

 

[R.Braverman]

OK:
1. I misinterpreted what you said. I though you were picking 2-3 spots and dealing with them all at once, I didn't realize it was one step/area at a time. My hand isn't that steady, even with the Wacom.
2. The way you're proposing, means a section item at a time, correct? If I didn't get that wrong, it would appear to me to be a pretty intense operation, eh?
3. I just did the fencing, saved the image and went to see if I could do the "rope" box (that's not what's it's called but I'm lost right now) and the fencing is back to it's blue color - I missed a step - right?
4. I just looked into the image and there are too many areas on the left that have no corresponding area on the right. For instance, look at the calm water on the left in front of the boat, and then look for another area of calm water that's correct.

 

[thebestcpu]

Hi @R.Braverman
Getting the most precise result can take a bit of time.
Some less precise ways can be considerably less work, which I will show one approach.

We will use the Hue Saturation Adjustment Layer and selectively change only a range of colors.

You can see from the image below that I picked a range of colors in the blues.

Here is a link to a YouTube video on how to selectively adjust colors with the HS Adjustment Layer:

I clicked on the white portion of the hull of the left ship to make the selection, yet one could also manually adjust that color range for fine-tuning.

I used the Photoshop Color Sampler tool and selected the wood fence on the left and right. In the Photoshop info panel, those selections are shown at the bottom of that panel (shown). It initially shows the numbers in RGB, but I click on the RGB text and change it to HSB.

Now, you can see both sides of the image's H, S, and L values. Then you move the HSL Adjustment Layer sliders until the the left and right numbers match up.

Since it is adjusting just the blue range of colors, the rest of the image is not changed much, and the left side becomes a lot closer to the right. If you look carefully, there will still be some differences. You can play with the color range being adjusted and/or the amount of the adjustments.

It won't be as perfect as painting, yet a lot less work.

Just another approach to consider.
John Wheeler

 

[R.Braverman]

A duh moment:
Look at what I upp'd, that area was part of something else and got stuck/overlaid etc on top of this image, parts of it are transparent. If you look behind parts of it, you can see what is really there.
I think this changes (possibly permanently) things.
What say you?

 

[thebestcpu]

Hi @R.Braverman
On the other hand, all I see are parts of the image with the wrong color/tone, which would lead to the approaches I mentioned.
If something in the image plainly does not belong, there are always other options to replace what is there.
Part of this is deciding how much you can put into restoring the image with some significant learning curves involved. I, too, come across images that I can enjoy without restoration when they are beyond my own skill set.
Alternatively, post the full image on the Free or Paid Photoshop Requests forum for someone else to take on the restoration.
Only you can put a value on what path is worth taking.
That's my take
John Wheeler

 

[R.Braverman]

You're right on everything in that post.
I need to see what I can do, and what I'm willing to do.