In Davids Defence
With Digital copy work the first thing that is done is a white balance followed by a grey scale neutralization.
This gives fantastic control over colour balance and I am sure this is true advantage for colour accuracy of copied work.
I have done both methods and prefer the digital systems for this type of work. The ability to get into each stepwedge and colour balance
is the key.
Histograms and white balance add to the 'betterment' of analog and such theoretical underpinning should be INCLUDED here when such is pertinent. I think that that is a healthy balance to achieve for an 'analog' forum and, thus, prevents creation of an 'absolute' one which denies and segregates digital (any and all reference) from mankind.
There is much to learn from both that will help each 'capture' become more understandable. - David Lyga
Another glaring misdemeanor : Lightjet printers use RGB lasers, not CMY.... But I've got the best of both worlds : optical enlargers RGB.
David, I reckon even if the pictures had been made on film to begin with, they still would have ended up as digital prints. Certainly with architectural work, shooting large format for the movements and then scanning for precise colour control seems to be a no brainer. The most sensible option is using large format cameras with digital backs. On a practical level, optical prints for this type of work wouldn't make sense. Can't imagine you'd find many purist architectural photographers seeing as it's a commissioned job, rather than a fine art. When he insisted the capture "must be digital" I suspect it's less to do with 'accuracy', but control of colour. This type of work depends upon precison, not painterly subtle hues.
Oh bull shit. This is just another thread to talk about digital. I don't believe that is what APUG is about and not why I'm here.
Color purity in analog is based on chemistry. Color negative films are the best capture medium and color prints from them by any means (including scans and digital prints). Digital systems capture color reasonably well and have software to fix any problems. The real problem comes in grain and sharpness. Digital fails.
As far as image stability, analog films last for years while digital storage is rather fugitive. Analog prints are quite stable, and the prediction now is for Endura and CA prints to last for up to 200 years depending on storage. Digital prints are an unknown quantity at this time due to a number of issues. So, one cannot say.
"Color negative films are the best capture medium ..."
Coming from PE, this is rather confirming and even amazing. He is saying that chemistry is better than digital, at least in a theoretical sense; and that assertion is very uplifting for analog.
And, yes, batwister, 'control' is the underpinning of digital's 'legitimacy' especially with conservancy that must be 'hue true'. - David Lyga
Ron - as you should know, "predictions" of print life based upon brief accelerated-aging torture tests are basically shoot-from-the-hip extrapolations based upon calculators with a great big BS Coefficient buttons. The best of the chromogenics, CAII, is by Fuji's own estimation
expected to have significant yellowing due to residual couplers within fifty years. That doesn't stop me from printing it. I certainly won't be
around another fifty years to find out, anyway. Let's just say the consensus is, that chromogenic prints have indeed dramatically improved
in recent years. But in terms of initial capture and color accuracy, I'd say we've lost the most accurate chrome films, namely tungsten films
and Astia, which were the best under controlled copy conditions. With the current neg films, I'm finding Ektar to actually be more accurate
than Portra 160 in terms of hues and shadow accuracy, though at a disadvantage in terms of latitude. Always something new to learn, it
Batwister - what on earth makes you think optical prints cannot be every bit as precise and controlled as digital ones? Just because the
current nerd generation can't function apart from an IV-drip of high-fructose corn syrup doesn't mean it can't be done, and be done even better! In terms of production schedules and certain kinds of architectural and forensic photography, digital in the high-end sense has some real advantages, but no absolute quality advantage. Sloppy work is sloppy work regardless. Sitting on one's butt punching buttons won't
change that. One still has to learn the tools intelligently, regardless of what those tools are in the first place.
I have had the opportunity to take the ICIS short course in image stability in 2006 and also to talk at length with Henry Wilhelm about the very questions you mention above. I have also been through the Image Permanence lab at RIT with Henry. Here are some of my thoughts.
1. Are you measuring dark or light stability?.
2. What is the temperature and humidity you will keep the images stored at?
3. What pollutants are present in the air?
4. What is your altitude and latitude?
I have seen direct comparisons of Kodak, Fuji, Agfa and Konica products side by side and I observe some interesting discrepancies. Fuji measures their light keeping at 500 fc (they win under these conditions) and Kodak tests at 200 fc (they win at these conditions). AFAIK, EK solved the yellowing problem back in the 60s. No material can stand up to UV or to some air pollutants such as SO2.
BUT, in comparisons with digital image stability, even prints, the chromogenic products win hands down. Added to the mix is image spread in inkjet prints. They dyes are low molecular weight and even though they are supposed to be anchored, they wander. This fact is hard to find on Wilhelm's web page, but it is (or was) there for all to see. And, of course there is the problem of magnetic image deterioration! None of that in film.
As for color accuracy and latitude, noting is better than the Eastman Color Negative films in both daylight and tungsten. But we cannot easily use it as this family is an MP film.