This is a blend of a normal visible-light image and an IR image of the same scene at the Missouri Botanical Garden.
Both shots: Canon 20D, Tamron 28-300 @ 28mm, tripod, WB=daylight.
Visible image: ISO 200, 1/100 sec @ f/11. Minor exposure tweak in ACR.
IR image: added Hoya R72 filter, ISO 400, 10 minutes @ f/22. Reduced exposure 1 stop & reduced noise in ACR.
PSCS2: Converted the IR image to B&W, boosted contrast, burned the corners a bit, then sharpened selectively. Added the color image as a layer and set it's blending mode to "color", with about 60% opacity to keep the light, airy feel of the IR image. Then a slight crop for composition.
The 20D/R72 combination is a cheap way to try out IR, but takes a lot of patience; there's so little sensitivity left that exposures are VERY long, and with the in-camera noise reduction on the processing time is doubled. I usually do a test exposure at ISO 3200 and the lens wide open first, verify the histogram, then count off stops as I reset to a less noisy ISO and the aperture I really want to use. Exposures (on a bright sunny day) tend to be in the 10-15 minute range. Make sure the battery's charged before starting!
All comments & critiques welcome!
Chris









