If you want to see small gamut shortfalls in print, an easy way to do it is this:
1) download this printer evaluation image (it's a 40MB, Pro RGB tiff): http://www.outbackprint.com/printinginsigh...i048/essay.html
2) It is in Prophoto RGB and already sized to fit on a letter-size sheet, so save a native copy somewhere safe, then print it out properly using whatever your favorite paper and profile combination is -- I recommend Epson's Premium (or Canon's or HP's) Luster as it has a larger gamut than most matte papers and is readily available. Go ahead and use Epson's (or HP's or Canon's) canned profile for your printer if you don't have a custom one.
3) Now convert the test image to sRGB and print the sRGB version on the same paper using the proper paper profile -- the only difference is this time you'll be printing from sRGB converted to your paper profile, not Prophoto RGB to your paper profile as above.
4) Now compare the prints side-by-side. You should easily be able to see the poor rendering of the sRGB print on the greens and blues of the test patch squares just under the grayscale image in the test image. If you can't see any differences there, you are not printing properly or your printer/paper combo has an inordinately small gamut to begin with...
Cheers,
Thanks for the link to that test image, Jack. (You're not such a bad bloke after all .)
I've downloaded the image, printed the ProPhoto version next to the sRGB conversion (which I reconverted to the Prophoto profile for ease of printing since I'm on a 24" roll). I have to say that your test image merely confirms what I either knew already or suspected might be the case.
I know that Premium Lustre has a slightly wider gamut than Enhanced Matte. I have both profiles loaded in my system, but unfortunately for me, changing matte black ink on my Epson 7600 is too much of a hassle. I'll leave that chore till my matte black cartridge is empty, or my Enhanced Matte roll is finished (I use the South African method). I'd like to upgrade to an Epson 7900 but apparently my old 7600 has no resale value, and it's currently performing flawlessly (touch wood).
Some comments. First, I don't need to be convinced that ProPhoto RGB has a wider gamut than sRGB and ARGB and that Epson printers are capable of printing certain shades that are outside the gamut of both sRGB and ARGB.
The issue, in relation to Michael's rant, is whether such differences in shades of color, reproducible on the print with embedded ProPhoto profile, are significantly different to what one might see on the monitor. My view is, they are not, based on the performance of my own equipment and profiles (courtesy of Bill Atkinson - thanks! Bill).
Examining the differences between the two images on Epson Enhanced Matte, I see there are very few areas in the real-world sections of that test image where the Prophoto print is different. The differences are mostly apparent in the colored squares where a couple of shades of green and a couple of shades of cyan have merged into one shade in the sRGB image.
I've long been of the opinion that a major difference between sRGB and ProPhoto RGB is in the rendition of yellows. If we examine the autumn scene of the woods in your test image (at 100%), there's no doubt in my mind that, on both print and monitor, those yellow, fading leaves are more golden in the ProPhoto image. That difference, oddly enough, is not reflected as significantly in the yellow squares.
I should stress also that such differences are
more apparent on the monitor when proof setup is enabled, with either Enhanced Matte profile or Premium Lustre profile selected, in my situation.
The following crop of the colored squares from your test image shows the merging of the two shades of green and (separately) the two shades of cyan. The differences in the autumn woods' scene are only apparent in relation to my profiles for the Epson 7600. I tried to upload the two images of the autumn leaves with embedded Premium Lustre profile, to demonstrate the more golden effect of ProPhoto RGB, but failed. I presume the web cannot handle such profiles.
The image below has an embedded ProPhoto RGB profile. It's only meaningful in a program like Photoshop.
[attachment=16962:Colored_Squares.jpg]
Edit: Actually, the differences are so great that on my monitor those merged shades in sRGB, as opposed to the distinct shades in ProPhoto, are obvious without even opening the image in PS.