David's response just came in, it is below in blue. Have any of you had any issues using photo black for printing on epson premium matte canvas before? The friend I bought the printer off of never had issues with it and from what I've read online, it shouldn't be an issue.
Again: sorry about the delay. There are possibly two different things going on here.
First, there's the target print itself on canvas, which has an unusually light black. You're getting L in the 26 range, which means there just isn't as much density in the shadows as there would normally be. For comparison (I have an Epson 7900 and I haven't done any work on canvas, myself, but I have other measurement files from customers that have used canvas in the past) As with fine art matte papers, canvas typically has measured L values for black in the upper teens, not the mid-to-upper 20's. (Two different canvas measurement files that I have for Epson printers; and one of this is an Epson 4000 with the much older Epson inkset; has L = 17 for the black patch) The result is a much more limited gamut; the difference in gamut volume going from an L in the high teens to L around 26 is typically a 30% decrease in overall gamut volume, which is not a great thing.
To improve this: there's nothing you can do about the canvas itself, and you're using Epson inks, so you can't do better than that. The only question is: are you -sure- that you're using a media settings that's going to give you matte black ink? (The measurement file is noted with "Radiant Paper White" as the media setting, which would give you the correct black ink). IF you were using a media setting for a glossy/luster paper by mistake, it would explain the weak black and shadows. (Typically this is what happens when people try to avoid switching between photo and matte black in older Epsons, like the 4800/80 and probably also the 9800/80, and they end up printing with photo black ink on matte papers - which will always lead to poor results/weak blacks, no matter what Epson would have them believe) If you -are- using matte black ink, then there may be other media settings that will give you darker blacks, more density, and the gamut would improve.
So with all that said, I did some testing with your sample of the image in Photoshop, to see if I'd see the same banding in the softproof that you're getting in the physical print. If I leave black ink simulation turned off: no, I'm not seeing it. If I turn it on, then interestingly enough, I'm seeing stratification in those areas that's similar to what you're getting in the prints, although still not quite as bad. So that still tends to point to the limited gamut you're getting in your target print as potentially being the cause for this.
The second possibility (by itself, or in combination with the above) is the number of patches. You're using the 225 patch target, and if the response of the printer on canvas isn't sufficiently modeled by that, (if it behaves unpredictably enough "between" the samples provided by those patches) then the profile won't give you accurate results for the colors that fall "between the cracks" and the softproof also won't be as indicative of what would be going on when you actually print through the profile. In general, I'd probably have recommended using more patches when profiling canvas, in any case. So I think the other thing you should do is print and measure the 729 patch target (use the single page target, and print it large enough so that you'll get decent sized patches to measure) and start using that instead of the 225.
So for the next round of tests, my recommendation: (and then we'll see what happens):
- Make sure you're using matte black (if for whatever you're using photo black, switch to matte black)
- You "should", I hope, be able to make a target print where the black measurement has a lower L value, hopefully, much lower. I'd be looking to see 20 or less.
- Print and measure the 729 patch target; attach a new measurement file to the ticket; and also do a test print.
One other thing (I'm sure you've got Photoshop set correctly for printing, but just in case):
- What's your Photoshop RGB Working Space set to?
- In the Photoshop Print dialog, you're using Document (not Proof) when printing, correct?
