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Tuesday, June 24, 2014

The Spectrum Of B&W

IR What I Am • Faux Infrared • IR Filters • Cameras Converted To Infrared • More Than IR

Labels: ColumnTech Tips

Let It Go! The spring flower displays at The Butchart Gardens on Vancouver Island, British Columbia, look like the grounds of a "Frozen" ice palace when captured in infrared using an IR-converted Canon EOS-1DS Mark II and EF 24-105mm lens. The exposure was 1⁄180 sec. at ƒ/16 with an ISO of 200. (Yes, we're grandparents to princesses.)

IR What I Am
I love the look of infrared photography; it's such an interesting black-and-white interpretation of landscapes. Digital sensors are especially sensitive to infrared light, which is invisible to us, but degrades color images. However, images perceived in infrared light alone can be extremely creative. Blue skies intensify to nearly black, foliage is rendered a ghostly white, and a full tonal range is present with unexpected black-and-white renderings based on original colors. I once captured infrared images with IR film, but in the digital age, there are more options: inexpensive post-capture software (faux infrared), external filters and, for those with true commitment, camera conversions.

Faux Infrared
Any RAW color image can be "converted" in post-capture software to approximate an IR look. Some images lend themselves well to this Photoshop exercise, while other images don't come close. It's hard to predict the end result, so you just have to experiment. Russ Burden's OP "Tip of the Week" article at www.outdoorphotographer.com/how-to/tip-of-the-week/bw-adjustment-layer-explore-infrared.html#.U5XSlijYMso uses an IR Adjustment Layer. If you're into nostalgia, Steve Patterson takes it all the way to approximate the look of the old IR film, with a bit of softness and grain, in his tutorial at www.photoshopessentials.com/photo-effects/infrared-photo/.

If you want it done quickly and easily, just purchase Fred Miranda's Photoshop action at www.fredmiranda.com/shopping/DI for $8.50.

IR Filters
I've worked on my DSLRs with Singh-Ray's I-Ray infrared filter (www.singh-ray.com), which passes infrared wavelengths from 700nm to 1100nm, and Hoya's R72 and RM90 infrared filters (www.hoyafilter.com), which pass infrared rays above 720nm and 900nm, respectively. Place one of these very dark filters over your lens, and the only light that will reach the sensor will be IR wavelengths. If only it were that easy!

All of today's DSLRs and compact digital cameras have a filter over the sensor called a "hot mirror" or "cut-off" filter. Its purpose is to impede IR from getting to the sensor, which, as noted above, degrades a normal color image. In fact, some IR does get through, and because of this small amount of available IR, filters like the Singh-Rays and Hoyas will give you a real IR image. Be warned that the exposure will be long and a tripod will be necessary. With my Canon EOS 5D Mark III and an EF 24-105mm lens and the Singh-Ray I-Ray, I needed an ISO of 3200 and a 15-second exposure at ƒ/8. A Canon EOS 70D had identical exposure times. My colleague Robert Agli used a Nikon D800E and needed 15 seconds at ƒ/8 and an ISO of 800. These aren't recipes for quality images.

If you want better quality and more versatility in infrared capture, the best choice is a camera converted to specifically take IR.


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