This one took me some time to (1) muster the courage for and (2) work out: https://tinker.koraks.nl/photography/on-a-color-mission-comparing-two-ra4-color-papers/
It goes into a question that has played in my mind for a few years, but that I never really answered very thoroughly: what really is the difference between entry-level Crystal Archive paper vs. the more premium DPII for optical enlargement? The blog post above attempts to answer that question. It features some 'clinical testing' involving step tablets as well as real-world samples of comparison prints. It's way too much to quote here, so please have a look at the link if this subject interests you. I'll quote part of the conclusion I arrived at here, and will include a few of the dirty pictures from the blog.
Density plots for DPII (solid line) and Crystal Archive (dotted), for cyan (top left), magenta (top right), yellow (bottom left) and makeshift-grey (bottom right).
Color space/gamut plotted as a (horizontal) vs b (vertical) out of Lab for the dmax CMY patches; the larger gamut is DPII.
Example prints on Crystal Archive (top) vs. DPII (bottom); same negative, same color filtration, 20% longer exposure for the CA:
(Kodak Ektar)
(Kodak Ektar)
(Kodak Vision3 250D in ECN2)
The blog also goes into questions about crossover insofar as I hadn't addressed those in an earlier blog, as well as the notorious phenomenon of the brown, mottled blacks of Crystal Archive. For the latter, I have what I believe is a pretty watertight explanation.
It goes into a question that has played in my mind for a few years, but that I never really answered very thoroughly: what really is the difference between entry-level Crystal Archive paper vs. the more premium DPII for optical enlargement? The blog post above attempts to answer that question. It features some 'clinical testing' involving step tablets as well as real-world samples of comparison prints. It's way too much to quote here, so please have a look at the link if this subject interests you. I'll quote part of the conclusion I arrived at here, and will include a few of the dirty pictures from the blog.
What to make of all this? First and foremost: there are differences between these papers, but in the grand scheme of things, they’re subtle. From an objective quality viewpoint, DPII is the better paper: it offers higher saturation, a larger gamut, deeper blacks and has no mottling issues. It also is coated on a thicker base, but whether that’s better, of course depends on what you’re after.
This is also true in general: while the objective advantage is to DPII, subjectively, you may prefer CA over DPII for certain purposes. The higher saturation of DPII also means that it’ll more readily emphasize color casts, and it’s overall a more ‘punchy’ look. So if you’re looking to print something in very neutral or more subdued hues, CA is an easier paper to work with. On the other hand, if you’re printing something that relies on areas of solid black or otherwise very deep or saturated tones, DPII is the better choice.
Last but not least: the printed examples below demonstrate in my view very clearly that both of these papers (and the in-between variants like CA Supreme) are by all means suitable for optical/analog enlargement of C41 color negatives as well as ECN2 negatives.
Density plots for DPII (solid line) and Crystal Archive (dotted), for cyan (top left), magenta (top right), yellow (bottom left) and makeshift-grey (bottom right).
Color space/gamut plotted as a (horizontal) vs b (vertical) out of Lab for the dmax CMY patches; the larger gamut is DPII.
Example prints on Crystal Archive (top) vs. DPII (bottom); same negative, same color filtration, 20% longer exposure for the CA:
(Kodak Ektar)
(Kodak Ektar)
(Kodak Vision3 250D in ECN2)
The blog also goes into questions about crossover insofar as I hadn't addressed those in an earlier blog, as well as the notorious phenomenon of the brown, mottled blacks of Crystal Archive. For the latter, I have what I believe is a pretty watertight explanation.
