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Infrared Image Processing

Recently I acquired an infrared converted camera. Somebody on Ebay converted a conventional Sony A5000 by simply removing the IR filter over the sensor. Unlike many professionally converted cameras, my IR camera does not have any IR filter over the sensor.

So without a filter over the lens images don't look that different from a conventional camera. But I've been using a 720nm IR filter. To the eye the filter looks black. But through the camera you can see an image. And surprisingly the daylight exposures are very similar to conventional photography.

One issue that is very much subjective about the use of digital infrared is how to process images. There's no way to be true to what you see, the IR world is magically different! For most of the IR work I've done so far, I've converted to grayscale. And unlike conventional photography, I'm ok with seriously moving those sliders around. Opening the shadows and pulling in the highlights to the extreme doesn't look as hokey as that aweful HDR look.

Here I thought I'd share just one image that I processed three different ways. First, is the black and white version. Please note, all the foliage in this photo is a lush green.


The second version is takes the BW version of with the same settings and applies a custom camera profile I built using Adobe's DNG Camera Profile tool. The reason for this is that by default, Lightroom and Photoshop (as well as Capture One etc.) won't allow you to move the color balance far enough. Basically out-of-camera the images are off the charts color balance wise. You can download my profile to test here. This file should be placed here: Mac Users:
Users>username>Library>Application Support>Adobe>Camera Raw>Camera Profiles>PC Users: (If you cannot see this path, you may need to unhide these files
Windows Vista, Windows 7, Windows 8, and Windows 10: C:\Users\Username\AppData\Roaming\Adobe\CameraRaw\CameraProfiles.



And another popular way of dealing with color IR images is "channel swapping". So I took the second image into Photoshop (there's no channel swap option in LR.) So in PS, I added a correction layer and took the red channel and zero'd out red and moved the blue to 100, visa-versa in the blue channel.


So what'da think?





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