Archives for 2016

This is the 26th in a series of posts on color reproduction. The series starts here. In discussions on DPR about analyzing Macbeth chart photographs, someone whose opinion I respect raised the issue of repeatability of the results. I thought I’d start with the basics, and made a series of 16 photographs of the chart… [Read More]

This is the 25th in a series of posts on color reproduction. The series starts here. I’ve cleaned up the u’v’ plot from yesterday a bit, and have done CIELab and CIELuv chromaticity representations of the three-way camera/profile/raw developer comparisons. Here they are:     I added the color shadings to the Lab and Luv… [Read More]

This is the 24nd in a series of posts on color reproduction. The series starts here. I spent most of yesterday and today setting up for chromaticity plots with one reference and two arbitrary profiles, cameras, and/or raw developers. It doesn’t sound like that big of a deal, but it turned out to be the… [Read More]

This is the 23nd in a series of posts on color reproduction. The series starts here. Yesterday, in what some may see as an exercise prioritizing form over function, I added two chromaticity diagrams to the Matlab code, xy and u’v’. Here are some samples, for Lr Adobe Standard Profile development of a 3200K lit… [Read More]

This is the 22nd in a series of posts on color reproduction. The series starts here. Some profiles and the default settings of some raw converters have nonlinearities built into them. A case in point is Lightroom process version 2012 and the Adobe Standard profile, which together apply nonlinearities separately to the RGB planes, resulting… [Read More]