15 October 2010

I See in Infrared, Part I

My first foray into infrared photography (IR, for short) was ‘some’ years back in the film days. I tried a few rolls of Kodak’s b/w negative and color transparency films. The results were, well, interesting and as a budding hobbyist I found handling and usage quirky. Not an auspicious beginning.

Fast forward 25 years and by 2005 I had been shooting DSLRs for a little over a year. I remember cruising some online photo forums and seeing these completely captivating false-color landscape images and wondering what in Hades these were. They were odd, strange even, but still compelling. Further digging yielded that they were in fact digital IR photos. I started searching on the web how to get into this and found a number of very good sites. Do a Google search for “digital infrared photography” and many of these sites are still there offering the same great advice on digital IR. (In particular, the Eric Cheng and Andrzej Wrotniak sites were a big help to me.)  


First, a very brief IR primer. What we call infrared photography is really near-IR imaging. The distinction is important. Many folks think of infrared in terms of giving off heat. Thermal imaging is in fact long-wave infrared and is not of interest in our photographic explorations (there is a very good article on Wikipedia that discusses the different types of infrared radiation.) What we are capturing with near-IR cameras is a narrow part of the electromagnetic spectrum just beyond visible light. This corresponds to the wavelength range of 700 nanometers (nm) to 1400 nm. (Compared to the visible light range of 390 nm to 750 nm, and ultraviolet range of 10 nm to 400 nm.) Most digital camera sensors are sensitive in varying degrees to UV, visible and IR light. To control the usually undesirable effects of infrared radiation, manufacturers will install IR blocking filters over the camera sensor while UV effects are controlled via lens coating and the addition of after-market UV/haze filters. In order to photograph in infrared we need to circumvent that IR-blocking filter somehow. Or, do we…?

Many early digital point-and-shoot cameras were to some degree sensitive to the IR spectrum. After some research (check out

Jen Roesner’s site) I picked up my first Canon G1 (3.3 megapixels!) – which was by then quite long in the tooth (manufactured in 2000) – a lens adapter and a Hoya R72 (720 nm) filter. Because the IR-blocking filter was still in place a tripod was still necessary as even on super bright days, exposures were still measured in the low tenths of a second (at best). But what a world was opened up!

At first, what I call false-color IR imaging was of interest to me and my IR images mainly featured muted magentas and blues as I tried swapping channels and performing other feats of IR wizardry. But soon the pureness of B/W became the way I saw my infrared world. During this period of exploration I purchased a number of used IR-sensitive point-and-shoots including the very sensitive Olympus C-2020-Z (2.1 mp!) and the Nikon Coolpix 950, as well as deeper 780 nm and 830 nm filters. The Olympus produced a few really stunning images (one of which I still sell and is included with this post: the white reeds and water shot), while I was never happy with the performance of the Nikon. But, my go-to IR camera was the G1 and it traveled everywhere with me including trips overseas to France, Japan, Czech Republic, Scotland, Italy, and Iceland, where stunning images of landscapes and cityscapes were created.

Of the three filters I carried with me – a Hoya 720 nm, a Tiffen 780 nm, and a B+W 830 nm – the Hoya was the easiest to work with, as it included the lower end of near-IR waves as well as a bit of the high-end of visible light (in the red channel). On bright days though the deepest filter, the B+W, could and did produce truly startling images. The downsides to this mode of IR exploration – older point and shoot cameras coupled with lens-mounted filters – was that I always needed a tripod and just about any shots with motion, were going to produce blurs. And, of course, there was also the in-camera limitation of small sensor size + few megapixels = low resolution output + greater chance of noise.

Of course I knew about IR-conversions (wherein the internal blocking filter is removed from the sensor) for Nikon and Canon DSLRs, but being a lone-wolf Pentax shooter I was out of luck. Fuji (temporarily) saved the day for me and elevated my IR photography to the next level. More on that, in The Next Phase post.


No comments:

Post a Comment

Note: Only a member of this blog may post a comment.