Recap

So, in Part 1 of this 3-part series documenting my careful first steps in the area of infrared photography I discussed a few points that piqued my interest in IR photography. Some background details were described and I eventually sent of my K20D to be converted. Onto Part 2 we go!

He’s dead Jim!

After about a week or so of sending the K20D to Germany, I received the following message from the guy doing the conversion:

Today I have to come back to you with sad news. I did the conversion of your camera but there is a malfunction now. The camera does not tun on but reports an empty battery (blinking battery on the upper LCD). I have triple checked every cable connection and solder point, but I was not able to find the source of the malfunction. It seems to be a mainboard error, something that can happen when touching such “old” hardware.

Well so much for my breathless wait. However, my choice of camera may have been somewhat tainted as I found out while my camera was on its way. It finally came back to me how flawed the live view mode of the Pentax K20D really was. It did not rely on contrast detection AF but it would rather flip down the mirror, focus using the regular phase detect sensor, flip up the mirror before the shot. Kind of like touching your left shoulder with you right hand behind your back. Also, the K20D was not really great in the image noise department (anything over ISO400) and I had by now read up on ISO noise issues with IR conversions.

A change of plans, and camera model

And, yes, my contact came back to me almost immediately and offered to source me a replacement K-5 for a small difference of €80. A K-5 which of course is immeasurably more suitable for IR shooting due to its true live view contrast detect focus and superior noise performance. These improvements signaled the move by Pentax from Samsung sensors used in older models to Sony sensors. He said:

I think the extra money is worth it, because Color-IR (630 nm) is always very demanding on the noise performance of the sensor. By pushing the white balance to extreme values the noise will be amplified and becomes easily visible in the image. Just let me know what you prefer!

I agreed and a short week later, a Pentax K-5 together with charger and battery was delivered to my doorstep. First of all, it immediately felt so familiar to me as I owned the K-5 as well as its later incarnation, the K-5 IIs, for a couple of years. Only setback was a weak mainboard battery which caused the camera clock to reset every time I had the battery out for recharging. I quickly found out that this is not uncommon and can be “cured” by always having a second battery ready to pop in before the clock circuit capacitor got a chance to discharge too far. Some €36 later, that was all taken care of and my experimenting was about to begin in earnest.

Let’s talk software first

So, dealing with IR images invariably means a bit more processing is required because an IR image coming straight from the camera is pretty lifeless and looks weird, with some very flat colors and little detail.

Reading up in various places I started understanding the concept of swapping color channels, applying colour lookup tables (or LUTs as they are commonly called) and the distinct output of various IR filter types. From 550Nm (nanometer) wavelength which ends up a riot of bright colors and al the way to IR cutoff filters of 720Nm and more which result in almost monochrome images. I had selected the middle-of-the-road 630Nm to stay on the “safe side”. The color chart to the right of this paragraph and a good deal of guidance came from the website of the company which did the conversion of my camera, IRreCams in Germany.

I also read up on the importance of setting the correct white balance in the raw converter rather than in the camera as the latter will not be able to capture the extreme ranges required. Lastly, the already discussed noise beast reared its ugly head and I quickly familiarized me in the ways to control the beast (wherever possible). Luckily I have some experience in shooting high-ISO images and have a decent grasp of noise reduction methods, upsides and downsides.

To open-source or not to open source. Thàt is no question at all (to me at least)!

Shakespeare really had no way of knowing which horse I would bet on in his times, but I can assure you I had full confidence the image editing suite I have available to me is móre than capable of doing IR images justice. In some ways, this software will even outperform commercial software but in all ways it offers choice, tons of choice! Whether you decide to use one particular raw converter or another, one bitmap editor or another, one noise reduction software or another, open-source software users are spoiled for choice.

I decided on Darktable (version 3.8.1 at the time I started this blog, now up to version 4.0) for my raw conversions, channel swaps, white balance edits, color mapping (where necessary or helpful), contrast and clarity and loads more besides that. Darktable is capable of delivering a publication-ready jpeg image right off the bat.

For pixel edits, like taking out small dust spots, using GMIC for some artistic renderings, working with image layers, I have really nothing which can touch Gimp, now up to version 2.10.32 on my operating system. A true powerhouse, especially if decked out with all of the available plugins and scripts. Important ones would be liquid rescale, GMIC, resynthesizer to name but a few.

Lastly, Digikam and its builtin image editor Showfoto not only for tagging and rating images but certainly also for some edits for which I’ve yet to find a better replacement elsewhere. Especially the auto color adjustment and sharpening routines are great but it also allows HDR alignment and merging via align_image_stack and enfuse.

Next time, part 3, some examples and lessons learnt!

But for now, a sneak preview to the other part of my website which contains an album with IR images shot over the past few weeks. Have a look and let me know what you think!