John Schwaller and others have recommended a program called QImage for resampling images for printing. I bought a copy – it’s only 90 bucks – and tried it out. The program works sort of like a RIP, but without actually doing the rasterizing, since it only accepts files that are already rasterized. You can import images, perform some editing, crop, arrange images on pages, and print. Printing is accomplished through the printer driver, and is preceded by sharpening and resampling if desired. The resampling algorithms are many: pyramid, vector, Lanczos, Mitchell, triangle, Hermite, Bell, and bicubic, plus pixel resize (I think that’s the same as nearest neighbor), and two unique resampling functions that the program author calls Hybrid and Hybrid SE. The program has quite a few features, and it will take days to thoroughly learn it.
I printed out the test target using the default settings, which uses Hybrid interpolation with sharpening set to 5 out of 20, and resamples to 360 ppi:
The results are very good, favoring smoothness over sharpness compared to Photoshop bicubic (the white space between the two one-pixel gray lines is not as well defined), but producing crisp branches without causing the sky to become mottled. These are the best results so far.
Turning the sharpening off and selecting bicubic interpolation produces a result that is much softer than performing bicubic interpolation in Photoshop:
Before I figured out how to have QImage do the color management, I made two prints with the color management handled by the printer driver. The results are markedly inferior to letting QImage, or by extension, Lightroom or Photoshop, perform the color space conversions, particularly in the sky region of the photograph, where a lot of mottling and noise appears.
Hybrid, sharpening set to 5:
Bicubic, no sharpening:
Since I am now leery of printing from Lightroom when I need top-quality results, it seems that using QImage is a reasonable way to go.
Unfortunately, QImage is not available for the Mac, although it is supposed to run fine under Parallels.