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The Russell RGB working color space
Plenty has already been written about the pros and cons of various working color spaces. ProPhoto RGB is very large, good for archiving raw captures, but inefficient for most actual output. Adobe RGB has been a practical standard for some time, but the gamuts of many modern printers now exceed it. Bruce Lindbloom has designed Beta RGB as a more efficient alternative, wider than Adobe RGB, but not as wide as ProPhoto RGB, and using D50 as a reference white besides.
I recently obtained and profiled a Canon PIXMA Pro9500 Mark II printer (10 pigments, a little brother to the 12-pigment imagePROGRAF iPF6100). Its gamut, and that of my old HP DesignJet 130, slightly exceed even Beta RGB, mostly in the cyans and blues. At the risk of turning this into, “working spaces are like opinions, everyone has one,” I adjusted Beta RGB and came up with what I call, for lack of anything better, Russell RGB. It basically extends Beta RGB out a little into the cyans and blues. Also, I have personally settled on a reference white of 5500°K for the time being, and so chose this as the reference white for Russell RGB. The gamma is the same 2.2 as the rest.
Below are plots created with Monaco GamutWorks. Red is Adobe RGB, blue is Beta RGB, and black is Russell RGB. The large gray plot is ProPhoto RGB for comparison. The green and yellow plots are of Ilford’s profiles for the Canon PIXMA Pro9000 Mark II (8 dye inks), Canon PIXMA Pro9500 Mark II (10 pigment inks), and the Canon imagePROGRAF iPF6100 (12 pigment inks), all on glossy photo paper (IGSGP11_CANP9000 Mark II_PPPGIIn.icc, IGGFS13_CANP9500 Mark II_PPPGIIn.icc, and IGGFS13Sheet__CANiPF6100_SGPPmmo.icc). My profile for the Pro9500, made with an i1Pro, is almost identical to Ilford’s. Click on the links at the right to move the slice up and down the L scale (JavaScript required).
Right-click and save RussellRGB.icc [492 bytes], or use Photoshop to create it yourself. To create a custom color space:
Edit – Color Settings
Display “More Options”
RGB: Custom RGB...
Click “OK”
RGB: Save RGB...
Save as RussellRGB.icc
Another option for a working color space is to select PhoPhoto RGB in the Color Settings dialog, then customize it by changing the gamma to 2.2 and the white point to 5500. I call this ProPhoto RGB 2.2 5500.