And if an engineer says, they won't work so well now optically, that doesn't necessarily mean they won't work EXCELLENTLY if one knows how to narrow down the parameters to better than what they consider average commercial conditions
What this engineer says has nothing to do with optical printers needing to use the correct film, film & paper processing control, using the right light source for enlargement, etc. What he says is that the spectral sensitivity of the paper does not match C41 anymore. It's also not about spectral peaks, but the match between the curve shape of a C41 negative and the three HD curves of the paper. Hence, any 'solution' that affects the entire image area all at once will not work. This naturally includes everything to do with film & paper processing, projection light source in enlarger systems and filter stacks. The only darkroom technique that can make a difference, is supplemental masking, because it's the only image-dependent correction technique.
But you were responding to an incorrect assumption of mschem to begin with, or maybe just a typo, confusing LED exposure systems
Yes, I noticed this, but let it slip to not complicate things. But to be more accurate, this is how I see it: exposure systems for RA4 paper break down in roughly two classes:
1: Optical projection systems that project a physical C41 negative onto a piece of RA4 paper. This can be an enlarger with a dichroic or LED light source, or it can be an automated machine like the first generation minilabs. Confusingly, these optical minilabs did/do have extensive digital controls, making them look 'digital' from the outside to the unsuspecting viewer. They're in the core analog systems, though: a color-filtered light source shines through a negative and a lens assembly to project a direct image of the negative.
2: Digital projection systems that expose RA4 paper in a pixel-by-pixel fashion. No negative is used, and the image is fully generated digitally. The light-forming element can be a chemical or semiconductor laser. They can even be tiny individual LEDs assembled in a bar,
but I do not know if this concept is used for RA4 machines. I only know that these LED print heads are used extensively in (color) laser printers - confusingly they're still called 'laser printers' even though they don't necessarily use lasers...Since this technology is capable of decent resolution, large formats (by staggering several LED arrays) and high throughput, it wouldn't surprise me if it's also used in some RA4 production printers. But again, I have not verified this suspicion.
All approaches that fall into class 1 require a tight matching of the spectral sensitivity of the paper used to a C41 negative, and that the negatives are of consistent quality. Color shift can be compensated, and as such, different brands of paper and film can be accommodated. Color crossover cannot be fixed, other than through supplemental masking with a film mask that's made with, and for use with, the original negative. Systems in class 2 essentially "don't care" if the RA4 paper matches the curves of a negative, since there's no negative in use anyway. In these systems, the translation of digital image data to the correct RGB intensities on the pixel level is done through LUTs and ICC profiles, as
@Mr Bill mentioned.
What did you conclude, koraks, from this about the future of printing opticallyin his opinion?
Well, he didn't "conclude" anything for the future other than simply stating the fact
in the present that optical printing is not a production environment reality that they cater for, since all their customers have long ago moved to digital.
Which papers was he talking about, all Fuji papers or just some and in which case what are these that home darkroom printers should avoid?
The FUJIFILM papers apparently use only two emulsion sets. One they call the 'amateur' emulsion and the other is what they call the 'professional' emulsion. The various papers hence break down into two classes, depending on which emulsions they use. Within these classes, the individual papers differ in terms of the thickness of the image-forming layers and the interlayers. I've written a small piece about interlayers here:
https://tinker.koraks.nl/photograph...importance-of-interlayers-in-ra4-color-paper/
This also shows how it's quite meaningful to have different papers with the exact same emulsions, because their performance is different. However, what does not differ is the spectral response, since that is inherent to the emulsion.
What I have yet to verify is if both emulsions have already migrated to 'digital only'. This was not said explicitly, although it was implied, and there was absolutely no mention whatsoever of any papers currently remaining fully compatible with optical enlargement. The way this engineer explained it to me boiled down to a very firm "that ship has sailed long ago". Again, I'll see if I can get a very explicit statement on this. Apparently it's a necessary step for the more skeptical among us to accept that the RA4 world really has moved to digital a long time ago and that any 'legacy' compatibility is not so much there intentionally, but mostly by chance. For instance, the fact that we still get OK results from optical RA4 prints is mostly because the emulsions were never re-engineered from the ground up - they were incrementally changed, and in the case of the magenta/green issue, part of the emulsion was simply left out because it was no longer necessary. The remaining combination in RA4 paper retains enough of a fit with C41 negatives to still work, in a way.
Unfortunately it sounds as if this Fuji person is essentially saying that those with enlargers will not be able to make even OK prints so they have no future as far as he is concerned. Is he reflecting the Fuji view?
Again, it's not about the future, it's about the present. He didn't say anything about "OK prints", though. He said that you'll get colors alright, but that it will never be possible to get the full performance out of the paper in terms of gamut and color accuracy using an optical projection setup. I don't quite agree with this, because he left out the possibility of supplemental masking, but I also realize that this technique is beyond what most of us are capable and willing to do. This certainly is true for me.
What someone finds an "OK print" is subjective. That's why I keep saying that if one is happy with the prints they make, then that's all that matters. I've printed on papers for a few years that I have now learned are technically not fit for the way I use them. Do I think any less of the prints I've made? No. Does it stop me from making more? Certainly not. It only makes me realize that I'm seeing only part of the performance these papers are capable of. I was gifted a small sampler box with a 4x6" print on every paper they produce. I can tell you right away looking at those that in terms of accuracy and gamut, those prints are far beyond the quality level I will ever be able to make in my darkroom with the same papers - and using the same Fuji chemistry, in a roller processor, at the correct temperature, etc. etc.
As to "the Fuji view": the Fuji view is to make money with RA4 paper as long as they can. Paying customers all use digital exposure. That's the market they cater for.
If so what does he believe the home printer of RA4 paper has to do that enables him to print at home?
I don't know how this guy feels about it - not very strongly either way, I think, because his interest is in producing a paper that works great in the way it's intended to work: digitally exposed.
My personal opinion on this is that there are two things people like you and me can do to enjoy RA4 paper as it is today:
1: Enlarge in the darkroom and accept the results for what they are. They can still be gorgeous and worthwhile/fun to make, even if they can virtually not be made to look dead-accurate anymore and you may not be able to exploit the full gamut that the paper is capable of.
2: Use these papers the way they're intended, i.e. digitally exposed, and enjoy the full performance they have to offer. A wide range of commercial printing services are available where you send in your files and you get the prints in return. Pick any good lab you fancy. Personally I'd pick one that actually tells me what paper I'll be getting, because I happen to find that important. Fortunately, several labs cater to a more demanding crowd. Download the correct ICC profiles, calibrate your monitor and have loads of fun.
How many people here use LED heads or Laser/LED digital printers with color negative paper?
See above for the distinction between light sources. Don't confuse LED heads like the Heiland enlarger light source with a digital exposure system. They're different animals. As said, LED solutions like the Heiland system don't solve the problem.
I don't think there are many people here who use a true digital system. There's maybe one or two who appear to have half a foot in a commercial print operation; perhaps they're active users in the sense that they actually get near the equipment that makes the prints. But since Photrio leans very heavily towards analog and away from digital, I take it as a matter of course that there has never been much interest (and often even not much acceptance...) in digital output.
When it comes to amateur photographers
indirectly using digital printers - well, millions, evidently. Pretty much anyone who has their digital snapshots / photos mailed to them as prints uses these systems through a service provider. And why not? It's a great way to get really good color prints. It's in fact a very hard to beat way to make excellent color prints in an affordable way and with a minimum of fuss.
Don't get me wrong - I'm really passionate about darkroom printmaking. I'll keep doing it, also using RA4 paper - as long as it remains accessible and as long as I have the time and space to do so. But I'm also a realist in the sense that I understand a little bit about how this industry operates, and that doesn't mesh well with romantic and archaic ideas of how this used to work a couple of decades ago. The world has moved on; what's the point in trying to remain stuck in the past?
A week or two ago I had a visitor (he also registered on Photrio recently) and we made some nice RA4 prints from negatives he brought. He has since successfully printed several more, in his own (new) darkroom. I never asked his age, but I firmly put him below 30. 