Yea the deal is Canon has improved its permanence with the last Lucia inks. It is now between HP and Epson for color longevity while up there with Epson in gamut.
The color gamut, is more intense overall on the Canon and Epsons. For some people it can be significant, but for the work I do it has never been an issue because I just don't run into needing more saturation, even in the reds that were improved on the HPZ3200 over the Z3100. I'm not evaluating color models in color think, I'm making prints. But I'm not doing advertising work or making color match proofs for offset either. A lot of people do.
Hp has a much superior black density for monochrome work that is very visible on matte media. Canon beats it on the fiber gloss media but all are over 2.4 density there. The HP inks out perform the other two significantly in permanence on most all media for color work. For monochrome work Epson and Canon are excellent and beat HP for permanence, as long as you don't add too much color toning. The cyan inks that Epson uses for neutralizing carbon are also very stable, the magenta not so much. The reason for that monochrome stability is the Epson inks in particular are almost pure brown carbon (some say greenish-brown) and are not going to shift much if at all. The HP gray inks are primarily carbon, and are "cooled off" with other pigments when they are made, and encapsulated with a uv filter too, so that you can print out of the quad configuration and not use any color composite inks at all to neutralize them and still have a longevity >250 years in daylight. But all the HP Vivera inks, gray and color, are all designed to fade at the same rate, and that is their version of innovation. They are the only outfit that does that. Personally I like this as it allows me to tone to sepia, warm, selenium, or neutral, or even split tone, with no change in longevity in any of the channels. And I don't have to spray them with a uv spray because they already have that built into the ink itself. But according to Wilhelm's data, Epson can out perform the HP bw on some media by over a hundred years ( 350 years or so vs 250 years). But once again better not put too much color ink in the mix and he certainly doesn't spell that out. Which makes a difference no doubt. I believe QTR was the ultimate solution for turning off the problem color channels with Epson inks but Epson has shut that down on the latest Epsons like the 9900. Real smart Epson, duh.
One thing very strange though if you look at these Wilhelm postings for all of the inksets, is the significant disparity between the Wilhelm commissioned tests for Hahnemuhle and Canson on all these printers, and the Epson, Canon, and HP tests of the same or similar media with the same ink, that the printer manufactures commission. The printer company tests usually out perform the paper company tests with the same set up. Odd. That is one of the reasons why I trust Aardenburg Imaging far more than Wilhelm Research for accurate data. The criteria with Aardeburg is spelled out clearly so there is no hidden method for determining these figures.
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