I recently decided to upgrade from my current infrared-converted, taking advantage of Kolari Vision‘s Anti-Reflective coated glass. In the process, I once again considered my filter choices. Although I had some decent results from a 665nm filter from another infrared conversion house, I was not satisfied with the overall results and had Kolari Vision swap the 665nm out and install a 720nm filter. I always thought the 720nm filter provided the best overall balance of bright white vegetation and false color processing capabilities, but admit suffering from occasional bouts of ICE –Infrared Color Envy. Some of the photos taken with the 590nm filter are well rather gaudy. But I have also come across some that are jaw-droppingly gorgeous.
I have occasionally found ways to boost the false colors of my 720nm photos and have seen an extra splash of color from others using the same filter. Before settling on the 720nm filter (again), I decided to challenge my preexisting notions regarding the 720nm’s ability to process false colors.
My current Kolari Vision 720nm IR filter combination provides great results, but the false colors are rather limited, apart from the blues. The series below is representative of my standard 720nm processing technique.
RAW File With Custom Lightroom Profile:
As you can see below, pushing the Yellow Slider in the Hue/Saturation Control does very little to the color of the vegetation. Admittedly, I could change the White Balance setting to increase the yellow saturation, but I happen to like this look.
Here is the final image after a layer of Silver Efex using the Luminosity Blend Mode. I find this look quite appealing for most of my IR photography.
2) Infrared Filter Selection
As you can see from Kolari Vision’s filter guide (other conversion companies’ filter examples are similar), fans of brightly colored IR photos will likely opt for the 590nm. There is little to suggest the 720nm might also yield some of the same splashy colors as the 590nm filter. These charts also show the relative ease of getting good whites out of any of the filter choices.
Charts such as the one above should always be considered as general guides. Different vegetation reacts differently to IR light. In some cases, it is nearly impossible to affect the color of some vegetation, even after desaturating and boosting the luminance associated with the yellow slider in Photoshop’s Hue/Saturation Control. If you have taken IR photos of evergreens, you know what I mean.
Of course the beauty of any IR filter lies in the eyes of the beholder, particularly if he/she is paying for the conversion. Each IR filter represents a trade-off (more false color options / duller whites or brighter whites / less false color options). The trick is finding out how to produce the widest latitude of results for the IR filter of your choice and quickly adjust your IR workflow process as needed.
The Starting Point – White Balance
The first step is shooting in RAW and having a Solid White balance setting in your camera. The next step is creating a White Balance setting in Lightroom with enough latitude to mimic the White Balance setting in your RAW file (assuming you are using for managing your photos). I covered this in a previous article on post-processing infrared photographs.