color correction with known references

mmccoo

Hi,

I have a bunch of pics that I'm trying to color correct and I'm thinking of a workflow that should be easier but I haven't found a tool that supports it.

I have a group of pictures from a party with varying lighting conditions. Because I have some of the same people in multiple pictures it seems I should be able to use them a cross references.

Say I have two pictures of the same person. In one of the pictures, I have known neutral. In the other, I don't. For the first, it's easy to fix with the eye-dropper. What about the other one?

Here's what I'm thinking. Once I have a corrected picture of that one person, I'd like to be able to select a color on their shirt and label it as X. When I go to the other shot, I should be able to tell it, "this is the same color as X, make it so.

Make sense?

Miles

SloYerRoll

mmccoo wrote:

Hi,

I have a bunch of pics that I'm trying to color correct and I'm thinking of a workflow that should be easier but I haven't found a tool that supports it.

I have a group of pictures from a party with varying lighting conditions. Because I have some of the same people in multiple pictures it seems I should be able to use them a cross references.

Say I have two pictures of the same person. In one of the pictures, I have known neutral. In the other, I don't. For the first, it's easy to fix with the eye-dropper. What about the other one?

Here's what I'm thinking. Once I have a corrected picture of that one person, I'd like to be able to select a color on their shirt and label it as X. When I go to the other shot, I should be able to tell it, "this is the same color as X, make it so.

Make sense?

Miles

Sounds good on paper. I don't think it's viable in real life though. With my limited knowledge base, I'd recommend setting white point on all your shots vs. this method. If you reference a skin tone, you'll never hit the mark unless you select the exact pixel shade on every picture. And even the shade of that pixel changes every time the person moved and the lighting changed.

That sounds like more trouble than it's worth to me.

jfriend

mmccoo wrote:

Hi,

I have a bunch of pics that I'm trying to color correct and I'm thinking of a workflow that should be easier but I haven't found a tool that supports it.

I have a group of pictures from a party with varying lighting conditions. Because I have some of the same people in multiple pictures it seems I should be able to use them a cross references.

Say I have two pictures of the same person. In one of the pictures, I have known neutral. In the other, I don't. For the first, it's easy to fix with the eye-dropper. What about the other one?

Here's what I'm thinking. Once I have a corrected picture of that one person, I'd like to be able to select a color on their shirt and label it as X. When I go to the other shot, I should be able to tell it, "this is the same color as X, make it so.

Make sense?

Miles

Several possibilities I can think of:

1. The brute force method. Put a color sampler on the person's skin in your original image with the good color. Switch to the second image. Put a color sampler in the same place. Tweak the colors until the color numbers from the second image match the first. Some people might find this one easier in LAB mode because brightness differences wouldn't affect the color numbers.
2. The Match Color feature. Photoshop has a feature called Match Color that might do what you want. See http://www.heathrowe.com/tuts/matchcolor.asp for one example. Search Google for "photoshop match color" for lots of other tutorials.
3. Group into similar lighting. Group your photos into batches with similar lighting (e.g. all photos taken in one particular location), figure out the representative white balance adjustment for each location, then just propogate that setting to all the other similarly located photos. This works particularly with a RAW workflow, but can also be done for JPEGs in some of the newer tools.