PYRO in, Digital Out

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At the risk of suffering the attacks so many people do when asking innocent digital questions on this forum, here goes:

I am a DEDICATED large format photographer. I pretty much always use HP5 and pyro, and sometimes TMX when I have to use Readyloads.

Here's the question: I no longer have a full darkroom. I process film in the sink and scan it or send it to a lab for someone else to print. About 90% of my work is scanned and printed on an Epson 2000p.

Do you think it matters any more if I still use pyro? If I developed my film in XTOL or something far safer, would a final digital outpout print look any different?

Maybe what I'm really asking is what you have learned, found, or tested that resulted in your adjusting your photography for digital printing? We always tested films and developers for specific papers or light heads. But what film/developer combinations work best for digital output?

Thanks for whatever insights you can share.

DH

-- Dennis Halloran (dhall@boilingpoint.com), April 09, 2002

Answers

I'd be inclined to look at it the other way around. If you are getting good results with pyro negatives on the scanner, staying with that combination gives you the greatest latitude for printing them (I'm tempted to say "for real") later on in silver, platinum, kallitype, etc. if you ever get the chance. You might optimise for current scanner/printer technology, but that seems unwise since in a week or a month it will no longer be the latest/best thing. In any case, I don't know of any theoretical reason for a scanner to have trouble with pyro negatives as long as you've got full control through the software for optimising from a presca

-- Carl Weese (cweese@earthlink.net), April 10, 2002.

Dennis, I haven't compared Pyro scans vs. Non-Pyro Scans, but I can say that I scan my PMK negs and they look great. I have been using a Nikon 8000 and the scans come out very nice and "rich". I would recommend that you scan these in RGB as you would the color work. This way you can take more advantage of the stain during Photoshop processing.

-- Dave Anton (daveanton@shaw.ca), April 11, 2002.

Dennis,

I have had this same question plus another: do you or anyone here have a particularly good method for dealing with the pyro green cast in Photoshop? For what its worth, here's what I do: scan as an RGB positive (i.e., a transparency) so as to avoid any additional cast by scanning as a negative. Then use various methods to convert to grayscale taking care to use less green in the mix. But I think it would be possible and perhaps desirable to devise a standard convert-to grayscale method in PS for each of the plus through minus developments one uses.

My answer to your question is that evidently I think it is a good idea to continue to use PMK because that is what I continue to do!

-- John Hennessy (northbayassociates@earthlink.net), April 11, 2002.


John,

I don't convert to grayscale. I scan as RGB transparancy, then invert, then desaturate. Somehow converting to grayscale made the dots worse more pronounced and left a cast in skin and more neutral tones. Desaturating just works better, for me.

dgh

-- David G Hall (me@davidghall.com), April 11, 2002.


I scan the Pyro negs in RGB and get a purplish pos. Then go to "adjust hue/ saturation" where I change the purple to a warm brown/black and then desaturate until it pleases me. You could shift the other way to make a cold blue/black and then de-saturate. I wouldn't change unless I could get the grainless skies I can with Pyro.

-- Jim Galli (jimgalli@lnett.com), April 11, 2002.


On the issue of dev/proc/film/etc when the intended target is digital output:

This is exactly the workflow what I'm doing using now.

It is a tricky issue, as was already mentioned, the 'sweet spot' of your scanner is likely to change (via upgrade) long before you decide to stop using a given film (well, unless big Yeller decides to 'let' you stop using it) - so you either have the choice of test/feedback/optimise your entire process for your current scanner, rinse and repeat every 18 months, or pick a target and live with the results. The problem here is that optimising for the total system can definitely give better results because digital systems suffer from aliasing (both tone and pixel).

The repeated optimisation for scanner changes may be reasonable for a someone that goes through 1000+ sheets in a year -- but it isn't quite as obviously reasonable for someone like me that exposes maybe 100-200 sheets in a year. How to think of this in wet chemistry terms... assume that HC-110 in 16oz bottles was the ONLY developer that you could buy. Now assume that every bottle you get has wildly different chemistry - to the point where you have to recalibrate time/temp for each batch of stock you mix. Would you bother to calibrate at all, or just take Kodak's word for the time and leave it at that?

On the theme of converting from RGB to grayscale:

I had to do this for a number of scans and asked around some folks I know that were very much into computer based color. For what it is worth, they told me that the best way to convert in Photoshop is to convert the image from RBG colorspace to Lab colorspace (this conversion is not available in the LE version of Photoshop, btw) and then seperate the channels, then keeping only the L (luma) and working with that. I was much happier with the results than just doing the RGB->grayscale Or 'desaturate and leave in RGB'. I did not really look at grain issues with this, just the tone placement.

Good luck!

-- Tundra Slosek (tundras@draconis.com), April 12, 2002.


I have been using pyro with HP5 and FP4, scanning it in RGB like the other folks here. The theoretical advantage of pyro is that you get the stain more in the highlights, and paper is more sensitive to the blue light (inverse of yellow). I have found that by adjusting the colors pre-scan and using more blue, I get the same effect of "creamy" highlights with slightly greater "range" -- the resulting scans can almost look like platinum. However, since the negative density range is below that of most scanners, the non-blocked up aspect of pyro is less important. One could probably do the same thing using curves. However, as others noted, I do some contact printing as well and like to keep options open.

-- michael waldron (michael@cadogan.net), April 12, 2002.

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