Brewing over Barrettgreg
An infrared shot of Barrett Lake without channel swapping.. For all the detail try large size.
I have been taking IR photos since 2006 and only recently figured out how to reliably get deep rich blue (or red) sky and white foliage like this:
Everything needs to line up perfect.
1. Get a custom white balance off of a white road line painted on the road in the most full harsh midday sun possible. A sheet or card of white paper is NOT white in IR. Neither are leaves. White road line paint by design is. By that I mean it produces a even reflection of all wavelengths without strong absorption bands, including the IR spectrum. Consider it an almost perfect white body reflector. Plus they are almost always on a road near where you shoot and you can get a custom white balance for those particular conditions and time of day. Try not to get run over getting this white balance. I almost did :-(
2. Smog and air pollution is your friend. On really hot muggy and thick hazy days is when the sky becomes the most harsh and bright possible. Harsh bright = good. This is the kind of day where you have to have sun glasses just to see or drive. This is the kind of sky that returns the rich blue IR sky when RB channels are swapped. This is also how to get the rich red, orange, and yellow hues. Days with nice clear blue sky are the worst, avoid shooting on those days. In IR a nice clear blue sky is dark like night.
3. Angle and time of day of the sun. Shoot between 9-11 morning and 3-5 afternoon and try to always shoot with an angle toward the sun and with full bright harsh sun shining on the scene and subject. This is kind of difficult in practice. Often I shoot with the sun just right outside the edge of the frame. I step a few feet away and hold my hand out and create a shadow on the lens to prevent flare. I'm on a tripod so this in not a problem. This is a right on the edge kind of thing, sometimes my hand ends up barely showing in the edge of the picture.
If everything works out, then the foliage will come out near pure white and the sky will cast fairly red in the original camera file. When you do, you can push the saturation way over the top like +350% and then tweak the hue and color mixers to get this result.
With the saturation pushed so high chroma noise and banding can become a huge problem. The last secret is to use a powerful multi spectrum noise reducer like noise ninja or neat image to remove and smooth everything back out.
Hope this helps,