Thus spoke German military strategist Helmuth von Moltk. He was apparently right about war. The obvious corollary certainly applies to photography.

And thus it is with my infrared trees series.

Let’s start with lenses. I started out with the LifePixel-modified Sony alpha 7, the Coastal Optical 60mm f/4, the Leica 28mm f/2.8 Elmarit-R, and the Zeiss 15mm f/2.8 Distagon ZF.2.

The 15 is too wide for most things:

The Coastal Optical is an especially nice lens when used with the LifePixel SuperColor filter, which passes both blue light and IR, since that lens can bring both bands to a focus at the same point. It is also very sharp, although that turns out not to be too important given the next point. I’m finding myself thinking pretty wide in this series, and thus I have to stitch a lot of images with the 60 to get one pano. This picture took 68:

The 28 seems to be the most generally useful focal length of the three that I’m using. However, I have a problem with the Elmarit-R. I shoot into the sun a lot in this series, using tree branches to partially, but not completely, shade the lens:

Under these circumstances, the Elmarit-R often has artifacts that are a lot of trouble to clean up. I am switching to the Nikon 28mm f/1.4 D, which is not as prone to this kind of thing.

I have been experimenting with adding visible light blocking filters in front of the lens, especially when working with the 28mm lenses. This serves to limit the bandwidth of the light that falls on the sensor, and makes it easier for the lens to achieve good focus without stopping down a lot.  I usually use the moderate cutoff wavelength provided by an R72 filter. However, now there’ s less light, and, at the ISOs a feel comfortable using, the shutter speeds are getting a little long. In order to deal with that, I bought another a7II, and sent it off to LifePixel last week for the installation of their standard IR filter. With the IBIS in that camera, I should be able to confidently use 1/15 second with the 28.

I know I said in an earlier post that I’d be ordering my IR cameras with an all-pass filter and providing filtration in front of the lens to achieve greater flexibility. I’ve since found out that, shooting into the sun the way I do, that any filter has a tendency to aggravate and flare or artifact problems.

On the stitching front, I had been using AutoPano Giga exclusively. However, I had some trouble when I was dealing with the Elmarit-R’s artifact that caused me to try PTGui instead. I like PTGui. I like its masking functions better that AutoPano’s. However, it needs more help to stitch to my satisfaction, so I’m concentrating on not having the artifacts in the first place, and have gone back to AutoPano in the main.

I started out trying to frame the sets of images in a regular fashion, relying on the fact that I was doing it all handheld to provide the irregular edges. Then I started deliberately changing framing and angles as I made the exposures. I now do that to some extent, but I’m relying on overshooting by a factor of two or three the number of pictures I need to get AutoPano to do a good stitch, and editing the image set in post to get interesting edges, and to have the right relationships between the objects in the image and the edges of the image.

I am not deleting the raw files, thinking that I may want to go back to them at some point. The downside is that, as I get more and more of them, it’s going to be harder to sort the wheat from the chaff. Lightroom is currently not much help here. There are rumors that the next version of Lr will have panorama capability. That might help a lot.