After my last blog, several people asked for information about using the Tint Wheels. The Tint Wheels can be very helpful to either introduce or remove color casts. They differ from the White Balance tools in that the latter alter the color cast of the entire image whereas the Tint Wheels affect specific parts of the tonal range. There’s a wheel for the shadows, the midtones and the highlights.

Most of the time I use the Color Balance sliders and/or eyedropper to adjust the color cast in my images. However there are times when that isn’t enough, particularly if I’ve shot under mixed lighting conditions. That’s when the Tint Wheels can be particularly helpful. Using the Tint Wheels I can adjust the warmth - or coolness - of the midtones independently from the shadows or highlights. Sometimes whites become too warm when there’s incandescent lighting and so you can decrease the yellow tint in the whites.

There are two ways to use the Tint wheels. The first is to manually click the center of the appropriate Tint Wheel and drag the circle towards the color you’d like to increase and away from the one you’re seeking to decrease. If you think of the Tint Wheel as a joystick, it makes it easier to use it. If you change your mind and want to reset a wheel to the default value, double click the center circle. Sometimes I want to add a little warmth to an image so I’ll move the highlight wheel slightly towards yellow. Depending on the image, I may also adjust the midtone wheel to make the midtones a little warmer.

The other way to use the wheels is via the eyedroppers which will cause Aperture to automatically neutralize the color cast in each of the three tonal segments. This is very similar to using the eyedroppers in Levels or Curves in Photoshop. To remove a color cast using the Tint wheels, begin by clicking the Black Tint eyedropper. The cursor will change to the Loupe tool and will display the channel and luminosity values so you can easily choose where to click. Click an area that should be nearly black. Aperture will remap the image to make that point neutral or as close to neutral as possible (all three channels will have nearly the same value.)

Repeat the process with the midtone Gray Tint eyedropper and the White Tint eyedropper. Note that you don’t have to select the absolute darkest pixel, nor the absolute lightest pixel. Choose a very dark, and as close to black as possible, pixel and a nearly white pixel and one that should be roughly a middle gray. You’ll see the position of the center circle change in the Tint Wheels. In the following example I used the Tint wheels to neutralize the image.

Tips:

1. When choosing the point to click with the Black eyedropper, make certain there are no bright pixels in the loupe because they can throw Aperture off. If there are, increase the magnification of the loupe or choose a different dark area.

2. To search for a pixel to click on with the eyedropper, click on the image and hold down the mouse while dragging the eyedropper around the image. If you want to try clicking on a different pixel after releasing the cursor, you must first reclick the eyedropper After each click, the eyedropper selector reverts to the normal cursor.