R=100, G= 64, B=100 is close, but a bit too blue. I modified the Matlab program to create a target with finer steps: I added the fine-step image as a layer in Photoshop, over the coarse one, and filled the Linear Dodge layer with R=93, G= 0, B=85. Here’s the layer structure: I photographed it,… [Read More]
Archives for December 12, 2012
Testing for ETTR, part 13
I mounted a 135mm lens on my D4. That’s the longest lens I can use an still get the whole target square in the image. I took a picture of a random magenta square to see how tight the raw histograms would be: The Rawdigger histograms aren’t super tight, but that’s about all I can… [Read More]
Testing for ETTR, part 12
I’ve been working on ways to reduce the number of iterations required to calibrate a camera using UniWB, while requiring the use of only two programs by a user of this technique: Photoshop and Rawdigger. I first wrote a little Matlab program to generate a 10×10 grid of samples with a constant green value of… [Read More]