cgardner Offline Upload & Sell: Off
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Peter Figen wrote:
While the Zone System might be inconvenient for 35mm roll film, it worked just dandy for any 2-1/4 system with interchangeable backs. I remember running into Henry Gilpin in Tuolumne Meadows around 1978 or so and he had different backs for his Hasselblad marked with which type of development that roll would get. For 35mm, a lot of us carried three or four different bodies for the same reason. But I have to say that I really don't worry about it as much as I did back then. Having a great drum scanner seems to have leveled the Zone System playing field. ...Show more →
Adams also used a Hasselblad in later years but that wasn't something most could afford as they were very pricey. I carried two Nikon F bodies back in the day but one was usually loaded with color transparency film.
The tonal range constraint was always the print range not the negative for B&W and color negative films. Scanning eliminated that constrain but introduced a new one, the dynamic range of the sensor technology on the scanner. The first RCA and Hell scanners used analog photo-multiplier tubes. Digital CCDs made desktop scanners possible, but they couldn't match the DR of photo-mulitplier equipped drum scanner. CCD and CMOS ranges have improved in scanners and cameras, but they still can't record detail everywhere in a sunlit outdoor scene, what Adams defined as his "normal" contrast scene baseline.
To find "Normal" development you do a test like this one I did in 1971:
http://super.nova.org/TP/ZS_Test.jpg
1) Shoot the same subject in direct sun on four sheets or rolls of film, all exposed the same for the Zone 1 shadow detail.
2) Develop each roll for a different time. In that test the times were 6, 6.5, 7, and 7.5 minutes. On B&W film exposed the same is with those 4 rolls the increased development time creates more negative density in the middletones and highlights changing the contrast of the negative.
3) Make "standard" #2 prints - max black on film border. Compare prints highlights. It's difficult to see in the photograph of the prints but as development time increases the shadows stay the same, but the highlights get lighter. With 6 min the neg. was "thin" in the highlights to they get burned too much on the print by the time the shadows are exposed correctly on the print. At 7.5 min. there was so much density in the brightest highlights such as the sunlit building behind her that they lost detail. At 7 min development the neg range fit the print range perfectly.
For the OP: That's the type of test you need to do initially to find the optimal negative development time for the sunny day baseline I suggested above. If you scanning negatives rather than making prints you'd want to do a similar test to find what negative development time / density range matched the DR of the scanner by scanning the four negs. then finding which of the scans had a full range of detail.
Desktop scanners use the same CCD and CMOS sensors as a digital camera so they have the same DR constraints and you will likely find you need/want a "flatter" negative (one with less density in the highlights — shorter film developer time) for scanning vs. making silver prints in the enlarger. What has made Diafine developer very popular with those who shoot B&W and then scan is the fact the range of the negatives wind up within the range a scanner can handle automatically because that developer isn't time/temperature sensitive like conventional developers such a Microdol X.
Drum scanners are still round and in use by people like Peter who understand the difference the longer range of the photo-multiplier tube based sensor make. When scanning they can "dig" further into the shadows of a transparency to pull out the detail, much in the same way a "Fill" adjustment to a RAW file in ACR does.
The bigger advantage that comes with digital capture, or film capture then scanning vs. silver print on an enlarger is the ability to manipulate the mid-tones independently, which is HUGE in terms of changing how the image content between Black and White is perceived by the brain.
Full Range Digital Capture Conversion
http://super.nova.org/TP/TowelGaryBW.jpg
Same file with Levels middle slider adjustment
http://super.nova.org/TP/TowelGaryLighterBW.jpg
The "hard" vs. "soft" impression is a reaction to the overall tonal gradient Black vs White, but also the gradient between those end points and the middle gray zone. What the middle slider does is move the 18% Zone V tone value on the print to different places in the scene content "globally". That is to say if you change the mid-tone on the face, any similar tone in clothing or background will also shift. Sometimes that's a good thing, other times not, depending on the content and message of the photo.
Even using the ZS the best result you can achieve is recording the full tonal range from black to white. The tonal progression in-between is linear due to the linear DlogE response of the film and paper, which is patterned after the logarithmic response of the rods and cones in human visual system.
When making a prints under the enlarger one can selectively dodge and burn to achieve as difference similar the second lighter / softer looking version above, but there is no ability to "globally" shift the midtone values as was done above digitally with simple Levels correction. Adams wound have given his left nut for a "Levels" or "Curves" adjustment knob on his camera or enlarger
Having done all the modern analog processes of capture and reproduction in the past and now doing them much more easily and faster with far better control digitally the only thing I can't do better today than I did in the 70s with B&W and the ZS is reproduce the full range of a "normal" 10 f/stop outdoor scene with a single exposure.
A digital camera appears to cope with relatively flat lighting effectively because few things are in shadows and the shadows are small and usually behind the objects in the photo as in this shot.
http://super.nova.org/TP/DR_FlatLight.jpg
But turn the camera 180° in the same light with the same exposure for the highlight detail and you get this result...
http://super.nova.org/TP/DR_Backlight.jpg
It is exactly the same technically in terms of capturing the tonal range of the scene, but perceptually it looks grossly underexposed because the content that is most important and familar, the towel and card, are not exposed "normally". Had I instead exposed by metering the gray card and reproduced it accurately, the limited range of the camera sensor would have blown the sunny highlights by about 2-3 f/stops.
Why does this happen? A "normal" scene like that (in ZS parlance) has a Zone 1 - 9 range of 10 f/stops. My digital camera can only record 7 stops with Zone 1-9 detail. Zones are not f/stops they are tonal definitions on print and scene. All scenes and prints have 11 zones: 0 max black on print/dark void in scene, to 10 white paper base/specular highlights.
Choosing to "peg" exposure to retain detail in the Zone 9 whites of the towel results in the camera recording everything darker that Zone 9 darker than normally perceived by eye when it scans around and adapts to highlight and shadow brightness.
http://super.nova.org/TP/HSS/_MG_5034_Zones.jpg
Because there is no way to make my camera sensor longer to fit the 10 f/stop range (as I could with B&W film by reducing development time to match the print range) I must find ways to alter the scene range to fit the sensor. One way to do that is by adding not one, but two flashes to light the foreground...
http://super.nova.org/TP/HSS/_MG_5035.jpg
That's not a perfect solution because flash falls off in intensity much faster than the natural light and the background remains .3 to 3 stops underexposed in Zone 9 - 0 in the shaded background. The solution to that problem is cropping.
http://super.nova.org/TP/HSS/_MG_5035_Cropped.jpg
The less of the underexposed background that is included in the shot the less the viewer will notice or really care that it is underexposed.
The point of these examples is to show one can achieve as much or more situational awareness with a digital camera with histogram and clipping warning and a full range subject / target as was obtained in the "good old days" hauling a view camera or four 35mm bodies and spot meter around. The most valuable part of the Zone System is the "System" part — the systematic breakdown of scene and print in terms of tonal scale and understanding how tones in the scene wind up reproduced on the print or scan of negative.
A basic axiom of process control is: "Control is only as accurate as the ability to measure the process." In that respect I think doing B&W without a 1° spot meter and the ZS approach to knowing the scene range at capture would be a confusing waste of time because until you gain situational awareness of how the range of the same location changes on sunny, partially cloudy, overcast days, or how the direction of the lighting changes the perception of contrast in flat, cross and backlight you won't understand the problem or be able to control it predictably.
B&W has limits, just like digital. But instead of sensor range it is print range. A #2 print paper (filtered or single grade paper) has a range of about 10-stops. That is to say you need to control development to match scene range and wind up with negative with a .3 x 10 = 3.0 density to make a perfect print on #2 paper if using the Adams ZS as he explains it.
With roll film not using the ZS but instead developed always to the same time "normal" time need to produce a good #2 print on a sunny day (i.e. same "normal" baseline as ZS) you will wind up with the optimal 3.0 density range on sunny days, but on overcast days the same scene might produced a 2.7 negative density range. If trying to dig the detail out of a shaded doorway of a sunlit white building you might meter a 12 stop difference between Zone 1 and 9 and wind up with a 3.3 density range. To get full range prints for the 2.7 or 3.3 density range negatives you will need to switch paper grade/contrast via. filtration.
The part of the workflow that will make you a better photographer technically is the spot metering / pre-visualization. That's how you realize there is a problem and understand how to fix it. The problem (too much contrast outdoors) hasn't changed, but the ways to fix it have. That's why I never leave the house without a flash on a bracket and a second one in my shoulder bag and keep the sun over my shoulder when I'm not able to use the flash to change scene range to fit sensor.
Old dogs can learn new tricks.
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