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You are here: Home / The Last Word / Testing for ETTR, part 21

Testing for ETTR, part 21

December 26, 2012 JimK Leave a Comment

Now we have two methods for UniWB that work just fine. One, the gridded search, requires only Rawdigger and Photoshop, and doesn’t make the user do any math beyond adding and subtracting integers. Newton’s method comes in two flavors. The simple monitor space approach takes a while to converge, but works well. The matrix-based camera space approach requires a spreadsheet to do the calculations, but converges fast. There’s a question as to whether the matrix that I came up with for the NEC PA301W and the D800E could be used for any monitor and camera. My guess is that it will provide faster convergence than plain monitor-space Newton’s method for almost all cameras and monitors.

Both the Newton’s method approaches can provide results whose accuracy is only limited by the repeatability of the screen shot numbers, which is better than the gridded search.

The Last Word

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