I am now spreading my color space net to include a wide variety of possible RGB working color spaces. I picked 13 for testing: IEC 61966-2-1:1999 sRGB Adobe (1998) RGB Beta RGB Bruce RGB CIE RGB ColorMatch RGB Don-4 RGB ECI RGB v2 Joe Holmes’ Ektaspace PS5 PAL/SECAM RGB ProPhoto RGB SMPTE-C RGB Wide Gamut… [Read More]
Archives for October 2014
Color space conversion errors with ProPhoto RGB — 15 bits
Now let’s look at ProPhotoRGB conversion errors with 15-bit quantization. I took all 16+ million colors in sRGB and converted them to PPRGB and back, quantizing to 15-bits per color plane after each conversion. The conversions themselves were performed algorithmically (no tables involved) with double precision floating point, and have errors on the order of… [Read More]
Color space conversion errors with ProPhoto RGB — 8 bits
ProPhoto RGB is not recommended as an 8-bit color space, but I thought I’d start there. I took all 16+ million colors in sRGB and converted them to PPRGB and back, quantizing to 8-bits per color plane after each conversion. The conversions themselves were performed algorithmically (no tables involved) with double precision floating point, and… [Read More]
New show at Sunset Center
As if all this color space conversion stuff weren’t enough, I’ve got a piece of a show opening tomorrow, under the aegis of the Carmel International Film Festival, and thanks to Officino Uno. It’s the Staccato series. We hung work today. Turns out we weren’t done. The curator decided she only had room for 6… [Read More]
8 bit color space conversion errors: sRGB to/from Lab
In the old 8-bit world, Lab had a bad reputation for causing posterization when photographers invoked even moderate editing moves. I thought I’d check out conversion errors from sRGB to Lab and back, with double-precision color space calculations, and quantizing to 8 bits per color plane after every conversion. I used this target image, which… [Read More]