Comparing Chromira (etc.) and Enlarged Neg Prints

[Richard K.]

Is there a website that compares a regular darkroom enlarger colour print with one printed from a digital file onto photo paper (Chromira, Light-Jet, etc.)?

Would you see a difference at say 20x24 size?

What dpi, bit depth etc. should a 120 colour neg be scanned at to produce a good 20x24 Chromira type print?

Is there a good source of information (either a book or web site) on this topic?

Thank you...

(I want to do a bit of colour work with my Mamiya 7 and am wondering if it's worth investing in a scanner to prepare files for printing 16x20 or 20x24 or whether regular darkroom lab prints will be good enough - like they used to be... )

[Jostie]

Hi
Speaking from experience, (as the head of digital imaging and work-flow in a UK based pro lab) I have set up various new continuous tone RGB photographic printers, (Lightjet, Chromira, Durst Theta etc) by first making an analogue darkroom print from a suitable large format colour neg then drum-scanning the neg and making a digital print, comparing the two and fine tuning the settings on the digital printer so that the two prints match.
There is never a 100% match between the two. This is not down to the printer, but due to the digitising of the negative during the scanning process.

Most, but not all of the differences that the scanner introduces (there will be more noticeable differences in a scan made on a consumer level scanner compared to one made on a well calibrated high end drum/Imacon scanner) can be corrected in Photoshop. The main difference that you are stuck with is the reproduction of film grain. The scanned images always appear to be less smooth (the grain is more defined which is more noticeable in areas such as a flat sky) than the optically printed version, not by much, but when compared side by side you will notice a slight difference.

Having said this, the advantages of being able to use Photoshop for your darkroom work against the limited set of adjustments that you have at your disposal in an analogue colour darkroom greatly outweigh these minor differences, so much so that 99% of my customers who still primarily shoot film will get drum scans and output digitally. After all, it is still going onto traditional, light sensitive, chemically processed, photographic paper.

[mortensen]

Interesting, Jostie! I've shot LF for a year and had my first ink-jet prints done a few days ago. They look good, but i hunger for analogue and light jet comparison. What lab do you work for?

[Jostie]

Hi mortensen
I work for a Lab on the south coast www.spectrumphoto.co.uk We were early adopters of the Lightjet which we have since replaced with a Chromira.

[Drew Wiley]

You can easily see the difference between the three different methods. But which one you like the best depends upon both the overall quality control, the specific
image, and your personal preferences. Direct optical prints are the most seamless,
though not many labs made good dupes; chromira can have a fine salt-and-pepper
graininess, and lightjet can have a slightly banding. Otherwise, you've got the whole complication of PS correction vs the various tweaks of direct printing.

[mortensen]

well, Drew, that's exactly the thing: I have no darkroom experience whatsoever (apart from developing BW myself). I wouldn't know which directions to give the lab or which contrast- and color corrections they offer. On the other hand, I've worked intensively with PS for nearly a decade...

thanks for your comment.