Archives for 2012

Half of me would like to drop this in-camera histogram calibration project, since I’ve gotten it to the point where it works better for me than the Guillermo Luijk’s process, and is good enough for my use with iterations on the final step, but I’ve started down this road and I’m not going to quit… [Read More]

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]

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]

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]

In the preceding post, the histogram for the D4 had more spread to it than the one for the D800E. It’s not the camera. It’s the lens. The D800E looked at the monitor through a 200mm lens, and the D4 through a 100mm one. It turns out that, with my 30in NEC PA301W monitor, that… [Read More]