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xkaes
16-Feb-2017, 13:09
Anyone here ever use it? Here is a summary. It's pretty si

http://www.subclub.org/twozone.jpg

161301

Doremus Scudder
17-Feb-2017, 02:54
This is nothing more than what many (perhaps the majority of) Zone System users do: i.e., meter a shadow (and base exposure on that), then meter a highlight (and base development on that). The Zone System user pays less attention to Contrast Index and more to N+, N and N- developments, but the result is essentially the same; low-contrast scenes get more development than normal and vice-versa. Zone Systems user normally spend time testing their development schemes to ensure they do indeed give the desired contrast instead of just reading a suggested development time for a desired C.I. from the film's data sheet.

I'll admit that for "easily-metered" scenes, I do the same from time to time. For more complex scenes, however, I spend a lot of time metering the mid-tones and figuring out how much separation I want there, and then how I am going to deal with the resulting highlights...

Best,

Doremus

Greg
17-Feb-2017, 13:57
To put some perspective on the article. Richard Zakia I knew of but only in passing. Hollis Todd I had as a teacher at RIT. Think the course was named something like Photographic Densitometry & Processes. His Photo class was all technical based around his book PHOTOGRAPHIC SENSITOMETRY, a study of tone reproduction. We got to be very good friends. Hollis's world was one of graphs, step wedges, densitometry, and gray scales. Taking images.... no. He was a researcher and not a photographer. His Two Zone system was I'm sure created in the lab and not by actually taking photographs. I don't remember even taking one photographic image as part of his course work. To him the H&D curve was the holy grail. He was one of the best teachers I had ever had.

Jerry Bodine
17-Feb-2017, 17:29
What Doremus said, and I would add a comment. Most/all of us know that preservation of negative details involves giving adequate film exposure. We test a film/developer combo to determine an Effective Index (usually different from the manufacturer's published ISO speed) to insure adequate shadow exposure, and in the process of testing for N-minus (reduced dev time) we might discover a LOSS of film speed, thus losing shadow detail. We would know from our tests not only which dev times cause this loss but how much additional exposure is needed. Valuable information indeed. Then delving into the challenge of nailing down reciprocity effect is a whole different animal.

Steve Sherman
17-Feb-2017, 18:27
I would suggest the Zone System has not significantly changed over the years, it is a means to determine shadow values, give appropriate exposure based on one's style and then measure desired highlight values and give appropriate negative development again based on one's own aesthetic.
What has significantly changed for me is where those values are placed on the curve and to what density the highlights are developed to, the change in negative design is solely due to quality Multi-Contrast papers and how they respond to that design change.

Cheers, SS

esearing
21-Feb-2017, 06:29
I kind of do the same thing. With my spot meter I pick the darkest areas of detail then save to memory. Then I find lightest area and save it to memory. Then I use the average button to get a middle value. I record all 3 EV values on my note card with zones I-X marked and determine whether I want to place the dark section on zone 2 or 3 (usually), or by putting the average EV value on my desired fstop for the scene. Some of my older shutters also have quirky speeds so I have to compensate some with an estimated time and perhaps even adjust the f-stop .

Depending on the total SBR and how much detail is actually in the mid tones and highlights I may adjust development time but I am finding most of my scenes fall between 5.5 and 6.5 stops.
I need to do some experimentation where SBR is 3-4 stops or 8+ stops.