DIGITAL INFRARED COLOR PHOTOGRAPHY
PRESET COLOR BALANCE
If you just leave the camera white balance on sunny or use auto white balance
you will find your images are predominantly red and look something like the
bellow image:
What I like to do is create a custom preset white balance by taking a picture
of grass, this way grass and most other foliage will look much more neutral
and the red cast is more tolerable. Make sure to just have green grass covering
the entire viewfinder. If the camera said the image is no good keep adjusting
the compensation dial until it likes the image for the preset, I found on
the D70 a compensation of -2 to -3 stops works fine.
You should end up with pictures that look like this one bellow:

CORRECTING FLAT IMAGES
It is quite common with infrared digital photography
to end up with an image that is quite flat and low in contrast
and tonal range, like the example bellow:

As you can see it
is quite flat, but you can fix it in Photoshop by stretching
the tonal range by going to Image – Adjustments – Levels.
The histogram may look something like this:
Drag the left arrow (black) to the right until it just touches
the point were the curve starts and drag the right arrow (white)
to the left to the point were the curve starts. Here is a screen
grab of what you should have done:
What you have done
is stretch the compressed tonal range to the full range of pure
black and pure white, giving you a much more
contrast and “pop” to the image. The resulting image:
If you want more contrast
you could drag the black and white points in the Levels dialog
more inward, clipping some of the
information and even further increasing the contrast. At this
point if you would rather have a black and white image simply
go to Image – Adjustments – Desaturate. But if you
are interested in color infrared images then read on.
INVERTING CHANNELS TO CREATE A BLUE SKY
Using Photoshop we can swap the red and blue channels
to change the red sky for a blue one. Here is our image:

With the image open
select Image – Adjustments – Channel
Mixer. With the channel mixer open select Red as the output channel
and drag the Red channel slider until 0% is displayed. Then drag
the Blue channel slider until 100% is displayed. Here is the
screen grab:
Now select Blue as the output channel and drag the blue channel
slider until 0% is displayed. Then drag the Red channel slider
until 100% is displayed, Here is the screen grab:

Click ok and now you
should have a blue sky. You can further tweak the color and saturation
of the image by going to Image – Adjustments – Hue/Saturation.
The image should look like this:

CORRECTING CLIPPED HIGHLIGHTS
On occasion you may run into an image that has
strange looking cyan highlights, like the bellow example:
You can correct this
in Photoshop by going to Image – Adjustments – Hue/Saturation.
In the Edit menu select Cyan as the color to work on. Your cursor will change
to the color picker tool, find a patch of this cyan highlight in your image and
click on it with your picker tool. Now drag the Saturation slider all the way
to the left, making the cyan cast gray. The cast is gone but our highlights are
now a muddy gray, to make the highlights normal highlights just drag the Lightness
slider all the way to the right. Here is how the controls should look like:

The image should look like this:

Hope this tutorial was helpful in getting the most out of your digital infrared
photography.