Quote Originally Posted by DREW WILEY View Post
A common misconception. Modern RA4 papers being "optimized" for digital laser printing does not in any manner make them less suitable for
direct optical printing. In fact, they've been simultaneously improved in this respect too. The relevant spectral peaks are identical in either
application. I won't go into the details, but I routinely print these kinds of papers in my own optical darkroom, and the results are superb.
Some do actually have issues, for example Crystal Archive seems to suffer from green (highlight) /magenta (shadow) crossover. For digital printing it doesn't matter at all because they supply the paper with calibration data so it always comes out of the lightjet looking good, but you get issues under the enlarger.

For lack of (Portra) Endura sheets, I've found the Aristacolor paper to be pretty good for optical enlargements. I haven't done side-by-side comparisons, but I've found it a bit easier to print with than FCA. I suspect it is Supra Endura but don't know for sure.