3 min read Photography

Image Processing examples

I've kept the photos on a different page so that they don't bung up the text/explanations.

Let's start with the minimal use of the script... dcraw converts the RAW file so that Imagemagick can convert it to a jpg file. Looks a bit red, & not quite what we are looking for. (Although this would be fine if the photo were a normal one & we were just converting to jpg)

dcraw -c /storage/emulated/0/IR/temp.dng | magick - /storage/emulated/0/Pictures/IR/column-nonIR.jpg
"Developed" from the RAW file, but without processing apart from conversion to jpg

Take that photo above & run it through a CLUT to convert to a black & white image, using the 'alias' of "set_clut.sh" (choosing the CLUT file & then using it on the RAW file)

dcraw -c /storage/emulated/0/IR/temp.dng | magick - /storage/emulated/0/IR/CLUT/CLUT -hald-clut /storage/emulated/0/Pictures/IR/columns-clut.jpg

Or, you could use 'set_IR.sh' alias to choose the colour changes to convert the RAW file to that fake aerochrome look that is on the first page.

dcraw -c -r 0.507 1.000 2.4492 1.0000 /storage/emulated/0/IR/temp.dng | magick - -modulate 100,150,-60 -color-matrix 0,0,1,0,1,0,1,1,-1 /storage/emulated/0/Pictures/IR/columns-IR.jpg
Fake aerochrome channel swaps (false colour)

Of course you could additionally use the same CLUT as was used earlier - you can see the difference in the image.

dcraw -c -r 0.507 1.000 2.4492 1.0000 /storage/emulated/0/IR/temp.dng | magick - -modulate 100,150,-60 -color-matrix 0,0,1,0,1,0,1,1,-1 /storage/emulated/0/IR/CLUT/CLUT -hald-clut /storage/emulated/0/Pictures/IR/columns-IRclut.jpg

Or you could keep the false colour look & apply a bit of fake lens distortion/lens correction instead

dcraw -c -r 0.507 1.000 2.4492 1.0000 /storage/emulated/0/IR/temp.dng | magick - -modulate 100,150,-60 -color-matrix 0,0,1,0,1,0,1,1,-1 -distort barrel 0.06335,-0.18432,-0.13009 /storage/emulated/0/Pictures/IR/columns-IRlens.jpg

Different photo, just so that we can distort it.

Serpentine lake

Well, that's a bit different (slightly over distorted, but you get the idea)

Proves the concept

One last example, this time a rough version of a "tiny planet", or maybe a tiny island (I didn't take this with a view to processing it like this, so the edges don't quite line up, but that gives you an idea of where the warping wraps. You could add an SRT distort added if you want to rotate the image).

dcraw -c -r 0.507 1.000 2.4492 1.0000 /storage/emulated/0/IR/temp.dng | magick - -modulate 100,150,-60 -color-matrix 0,0,1,0,1,0,1,1,-1 -distort arc 360 /storage/emulated/0/Pictures/IR/tinyplanet.jpg

There are a lot of options for making changes to the settings & the combinations of settings that are used on any given photo. These are just examples of the potential - the important thing is for you to experiment.

One last thing - the command lines here are the ones generated internally by the script. If you want to copy & run them directly then you'll need to add some quotation marks around the color-matrix & distort numerical parameters.

Andy