Jimís original point about the problems of making small inkjet prints was a perfectly valid one, and I for one will be very interested to know how he gets on with dye-sub printing as an alternative. Yesterday, though, I had a kind of Road to Damascus moment which will not entirely solve the problem but does make me re-think the whole issue.
I realised that I, like everybody else, have been trotting out this mantra that native resolution is 300 dpi for HP printers and 360 dpi for Epson. But then I remembered reading on Eric Chanís site that resolution for the Epson 3800 can be either 360 or 720 dpi, depending on the ďFinest DetailĒ switch. And somewhere else, I canít think where, I seem to remember a discussion which came to the conclusion that all the modern Epson photo printers are 720 dpi. So did that mean that even my good old R2400 actually had a potential output quality which I had never previously tapped into?
Now that Lightroom 3x has the ability to re-sample and output to print at 720 dpi, I could easily set up a quick trial. Remember that all my work is B/W, printed via the Epson ABW mode using Eric Chanís paper profiles. Whether that affects the results, I donít know. It shouldnít. For the test, I needed to create a situation where LR and the printer would be discarding information from the file, at least at 360 dpi, so I set up a small 5x4 ins print of a very detailed subject which was technically perfect (lighting, exposure, focus, no camera-shake). I then printed two versions at the highest-quality settings on the 2400, one from LR at 360 dpi and the other at 720.
Superficially, they look identical. But under an 8x loupe there is a clear difference, with more fine detail, smoother transitions and sharper edges on the 720 dpi version. In fact, I can even see the difference with the naked eye, because I have very short-sight and I can focus without my spectacles at around 6 inches. So the R2400 definitely does print at 720 dpi, otherwise it would simply have re-sampled the file to 360 and the prints would have been identical. Which presumably means that the 3880, 2880, 4880, etc can also do so.
Obviously, for most people printing large colour or B/W prints this is all pretty academic. At any sensible viewing distance, 360 dpi (or even 300 dpi for that matter) is quite enough. And as others have noted, you donít normally view your prints under a loupe. But for printing small prints it does make a difference. As I mentioned before, to include all the detail from my 39MP files at 360 dpi I would have to print at (more or less) 20x16 ins, or A2. But at 720 dpi I can print at 10x8 ins without losing any of the detail in my file. And below that, at 7x5 or 5x4 there is still a gain compared to using 360 dpi. Small prints are viewed at much closer viewing distances, and that little bit of extra smoothness is noticeable to me.