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Marcus Carlsson
26-Oct-2006, 10:54
Hi, in the good old days I used the Zonsystem.
Now when I have turned semi-digital (I scan the negatives) I wonder how I can calibrate my gear.

This is the way I wonder if it's the way to do it:
I first take three images and expose them like this:
Zon 0
Zon V
Zon X

I develop it like the developer say for N
The reason for this is that when I then scan should be able to see in the scanning software where the lowest and highest point is.

The zon V is for later purpose which comes now.
After that I take a VI and VII and develops it with various time (to determin the N-1 and N-2).

To determine the right development-time I scan the images and set the lowest and highest values for the scanner.
And here comes my question.

Would I find the right time when the N-1 and N-2 gets the same value as the Zon V. And what should I set the middlepoint?

Should that be exactly inbetween Zon 0 and Zon X when I did the first scan?

I use Epson V700 if that matters and I uses Epson's scanning-software.

/ Marcus

Bruce Watson
26-Oct-2006, 11:15
My take on this is different from many. I've been using it for years now and have to say it works very, very well for me.

I use a modified zone system for scanning. First I do the traditional EI testing to determine film speed (0.1 over filmbase + fog). Then I test for my N development time. The twist here is that I optimize for scanning. Instead of a Zone VIII of 1.2 or 1.3, I aim for a Zone VIII of 1.0. This negative would be too flat for easy darkroom printing.

And that's it. I only use my N developement. I find no need at all for the old N+ and N- times. The reason is the way a scanner works. It takes whatever density range you have on your film, from 0.3 to 3.0+ and spreads that range evenly over its digital range of 0-255 (8 bits), 0-4095 (12 bits), or 0-65535 (16 bits).

The purpose of the Zone System and others like it was to try to make it easy to make a print from the variable subject brightness range of the scene you want to photograph. It used the film as an intermediary - the idea was to match a density range on film to the range that best matched the printing paper. Thus the plus and minus developments. This idea doesn't match up with anything in the scanning workflow. A scanner gives you an exact match to the paper over a wide range of negative density ranges. That's its job.

Think about it. Play with it. Try it out. For me, this is what the Zone System simplifies to. Literally, I expose for the shadows and let the highlights fall where they may.

I'd never do this for darkroom printing - it would be a nightmare. But it works really well for a scanning workflow for me.

Leonard Evens
26-Oct-2006, 12:06
What are you using to measure the results when scanning? Scanning software typically shows you values for R, G, and B in the range 0 to 255. These values are only indirectly related to actual densities, and the relation is not fixed. It changes with the scanning software's evaluation of the overall range and with gamma. It is hard that way to standardize what you are doing. Vuescan allows as an option the possibility of seeing the actual densities above base instead. I haven't compared it to a densitometer, but it does seem to be to give plausible values. the last time I used the Epson software, it didn't appear to have that capability.

If you can read actual densities, then you just treat the scanner as a densitometer. Develop so that specific zones yield the desired densities above base, just as Adams recommends in The Negative. but since you have more fredom when you work digitally, you need not use the same reference values as Adams did, because those were designed for enlarging on normal paper with an enlarger.

Without being able to read actual densities, you would need to standardize on black and white points and on gamma so that you always used the same values, and even then, if my experience is any guide, the results might not be consistent. Another problem with using the RGB values is that how they appear in terms of tonal values, either on your monitor or in your prints will depend on how the monitor or printer is calibrated. With so many variables, it is hard to keep things straight.

If you want a source which is standard with respect to densities, try getting hold of a step wedge. I got one made by Kodak many years ago, and I suspect they are still available from a variety of sources.

Ron Marshall
26-Oct-2006, 12:16
I basically do what Bruce has described. I only do minus development now when dealing with a large contrast range 12-16 stops.

Brian Ellis
26-Oct-2006, 19:36
I still use the zone system for exposure but I never plus develop and my normal time is 3/4 of my old normal time. I do still minus develop when it's called for.

In general you're better off with a somewhat flat negative for scanning, which is why I no longer plus develop and why my normal development time is less than it used to be. While I think it's still desirable to get the best possible negative in the camera, I don't think that's as critical as it was with darkroom work. When printing a 21 step wedge in the darkroom you can only make a print that shows about 12-14 distinct steps. Where on the wedge the steps begin to merge and cease to be distinct steps depends on the contrast setting with variable contrast paper or on the paper grade for graded paper but no matter what you do a darkroom print of the wedge isn't going to show all 21 distinct steps (except with van dyke brown and perhaps other alt processes that I don't know about).

When you scan a 21 step wedge and print it on an ink jet printer it's possible to make a print that shows all 21 distinct steps. So you no longer have to deal with the limited range of traditional photographic paper and therefore making a negative that will "fit" within that range (one of the goals of the zone system) isn't the problem it used to be.

Kirk Gittings
26-Oct-2006, 19:47
I still do plus and minus developement (slightly underdeveloped for each), because I want a negative which will print well traditionally or digitally.

Bruce Watson
27-Oct-2006, 06:14
I still do plus and minus developement (slightly underdeveloped for each), because I want a negative which will print well traditionally or digitally.
What Kirk says is true. If you are ever going to print the negatives in the darkroom, optimize for the darkroom. Such negatives will scan just fine.

Only optimize for scanning if you will never take the negatives into the darkroom. Such negatives can be difficult to print conventionally.

sanking
27-Oct-2006, 06:39
I still do plus and minus developement (slightly underdeveloped for each), because I want a negative which will print well traditionally or digitally.

Same here. I always do plus and minus development with sheet film 5X7 and larger since I want to have the option of printing these negatives directly with carbon, kallitype or Pt./Pd. And I developer for a fairly high density range, about log 1.8. My LF negatives, which are developed in staining developers, scan very well so I don't find any reason for not plus and minus developing.

With medium format B&W film I just take an incident reading in the shadows and develop for about 15% less than N for scanning. These negatives are meant only for scanning as I don't print any more with an enlarger.

Sandy King

Kirk Gittings
27-Oct-2006, 06:56
Also I think there is particularly some benefit in the +2 range to developing that way. Adding a steep curve to a file causes slight noise geeraation in the transitional areas between the tones that are being stretched. This is not usually a problem UNLESS your aesthetic (like mine does) includes allot of manipulation which picks up on this noise and accentuates it. I have found the grain increase from +2 developement to be less objectable than the noise increase from applying steep curves.

Bruce Watson
27-Oct-2006, 07:58
Also I think there is particularly some benefit in the +2 range to developing that way. Adding a steep curve to a file causes slight noise geeraation in the transitional areas between the tones that are being stretched. This is not usually a problem UNLESS your aesthetic (like mine does) includes allot of manipulation which picks up on this noise and accentuates it. I have found the grain increase from +2 developement to be less objectable than the noise increase from applying steep curves.

I've scanned a couple of negs now (color and B&W) taken from scenes with SBRs of less than 2 stops. I can't see any noise at all in the final prints. How? Drum scanner. With my scanner (and most (all?) drum scanners from what I can tell) when I set my black and white points in software, the software in turn sets the log amp range in hardware. This results in a very low noise scan.

Now, if you are using a CCD scanner, particularly a "consumer flatbed" scanner, then I'll agree with Kirk that N+ developements become a lot more attractive.

Kirk Gittings
27-Oct-2006, 20:36
I largely agree with you Bruce and I should have included that caveat. Good drum scans have so little noise that the problem of noise accentuation with steep curves and subsequent tone manipulation is not much of an issue. It is mainly though not exclusively a problem with consumer level scanners. On flat scene that I know will need allot of manipulation particularly in the sky, I will do an appropriate + developement, then have a good drum scan made and proceed. Having said that your work does not appear to include allot of tone manipulation hence as I stated...........