CatalinaUnderwaterPhoto.com

In part one we talked about the diferences between color correction and color adjustment, and about color casts. If we follow along with the reasoning in pt.1 we find color correction is an actual discipline. But does it concern the underwater photographer? Is there an advantage to applying color correction techniques the way a reproduction specialist might, as opposed to color adjusting as most photographers normally would? The answer to this comes back to the idea of a “color cast.”

When shooting underwater in natural lighting (everything here is about natural lighting photography underwater), the results are commonly similar to our example photos on the left hand side of these two posts. This is a color cast problem. Most photographers wouldn’t go there. “It must be the white balance, or maybe I can adjust it with HSB controls.” This is where most photogs would start and that’s fine — if you’re not underwater. But the science behind it all says differently. White balance is controlled by the light source, sunlight, tungsten, fluorescent, etc. So let’s think, the ocean is lit by the sun, problem solved, it’s not a white balance issue. It’s easy to set the camera to sunlight WB. The only difference between us being in direct sunlight is that we are under a body of water that is filtering the sunlight. Filtering it through a blue-green medium, adding a blue-green color cast to the whole environment and therefore the photo. See this post I found on scubaboard.com for an excellent detailed sciencentific explanation of this concept.

And so “fixing” underwater photos becomes just one big color cast problem. Hmm… Now look at the example photos on the right hand side of the posts. They are greatly improved from the originals. They have been “adjusted” using standard “correction” techniques, with one “move” in photoshop. To put it bluntly, you would never get natural looking results like this by using either WB controls or HSB controls not matter how many moves you made. The example photos are digital but the same holds true if you were scanning slides, most of the “correcting” could be done during scanning.

So sure, I’m concluding real world scanning and color correction techniques are more than relevant to underwater photography. In fact, that’s the cool thing about photoshop, the program was originally commercially distributed by BarneyScan as software to control their slide scanner through the earliest models of Macs. It’s earliest most basic controls are still the heart and soul of the program, the most powerful and useful to know.
(©2010 Daniel Mendoza, CatalinaUnderwaterPhoto.com. All Rights Reserved.)