CarlsArt Newsletter

Inside This BONUS Issue:
Texture Tutorial - Photos to Textures #3: Color Correction
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URGENT NOTICE: I have a small amount of CDs available for only $47 (from $159)

Photos To Textures - Part 3
Color Correcting Your Texture

Why Color Correct?

Whenever a photo is scanned, or taken with a digital camera, the image usually is not perfect as is. Color correction is the process by which any color casts are removed, and the full range of brightness values are restored to the photo, that may have been lost or degraded by the capture process (photo or scan).

This is best shown as opposed to talked about. Often you'll take a photo and think that it's fine the way it is, and often it is acceptable. But I'm going to show you how to determine scientifically whether a photo or texture is utilizing it's full contrast range, and how to quickly and easily restore the photo if it is not.

This technique is not only for textures, but should be done for every photo you take. Rarely a photo will be fine, and not need correction. But in my experience, at least 80% of all photos can be improved by these techniques.

Here is a before and after of a photo in which I color corrected. This brings back the full range of lights and darks to the image. Note that not all photos need full dark and full light contrasts. High-key photos might not have black darks, for instance.

Original photo

Color corrected

Here's how to do it. Create a new "Levels" adjustment layer above your image (click the black/white circle icon on the bottom of the layers palette). Notice the histogram. This shows the number of pixels of each luminosity. This curve shows a peak in the middle of the range. This equates to the dark and light grays. If the image had full blacks and whites, this curve would extend all the way to the left (blacks) and right (whites).

Drag the leftmost arrow to the beginning of the curve. This sets the new black point to the darkest greys. Then, move the rightmost arrow to the end of the histogram curve. This sets the white point to be set to the lightest lights existing in the image.

This restores the image to a full range of lights and darks, and has a dramatic effect. You may wish to drag the center slider, the gamma slider, to lighten the overall image, or to darken it, without affecting the white and black points.

(On this note, I should mention that if you ever need to simply lighten or darken an image, NEVER use brightness/contrast, but use levels instead, by dragging the center gamma slider).

Next, if the image has an unwanted color cast, or if you wish to give it a color cast, choose a channel from the Levels dialog. In this case, I wish to make a "yellow brick road" texture. I choose the blue channel, and slide it's gamma slider to the right, which darkens the blue, and thus produces a yellow result.

After color correction, we are ready to go on to make the tile seamless. That's covered in my next lesson!

Carl

URGENT NOTICE: I'm giving away a small number of full CDs (City and Urban Exteriors) for only $47. That's 70% off the normal $147 price! I made a slight error when pressing the first run of CDs, and it turns out the HTML graphical guide doesn't work for MAC users on these CDs because the filenames all have greater than 8 characters. All textures are 100% usable, it's just that MAC users can't use my custom graphical browser. For PC users, the CD is 100% functional, it's just like the $159 version. Due to my screw up, I'm letting this lot go for only $47 each, and once they run out, the price goes back up to $147. Be sure to order today if you are interested.

• How to hand craft realistic bump maps
• Using alpha channels vs. transparency maps
• Making your textures seamless
• Creating Black and White textures
• How to Add Dirt and Grime in Photoshop
• Texture Maps vs. Procedural Textures: Pros and Cons
• And whatever you want to learn - just ask me, and if it has wide enough appeal, I'll develop a tutorial for you!
  

Your feedback is critical, as it drives the content on this site.Did you find this tutorial useful? Was it too advanced, too simple, or just right? What would you like to see here next? Send your ideas to me at carl@carlsart.com.