04-11-2012, 08:15 AM
[quote name='Frank' timestamp='1334127274' post='17428']
Thank you, Wim. I see it better now. As far as I understand, the Zone System technique itself does compress the DR, what it does in the recording process is to "map" the tone of the scene onto the film (more or less) in a way designed by the photographer. So, when you say "Using Zone System techniques it is possible to get 15-16 stops recorded at about 10 stops (or less) on film" I guess you also mean using the GND filters to compress the DR. Am I right?
So, if GND filters (or digital HDR) are used, the DR that can be recorded by films/sensors are extended. Without these DR compression techniques, the "intrinsic recordable DR" of modern digital sensors indeed already exceeds the "intrinsic recordable DR" of even B&W films, if I understand your comments correctly.
Best regards,
Frank
[/quote]
Mr Adams did not get 15-16 EV from 10EV film. He used black and white film, which (depending on which type/brand/era) will have upto 14EV. But that 14 (or 10 or whatever) EV is what can be measured after development. and that is then at a set development time. After the development, that is than that. No way to get more DR in post processing. However, Mr. Adams did something quite particular during development of the film. He used large format cameras, so he had large format negatives. He developed parts of one negative in different durations. So, lighter parts in the photo he let develop for a different time than darker parts. This then resulted in the film showing highlights darker than with normal development and deep dark lighter than with normal development, extending the DR.
In post processing (putting that negative as positive in print on paper) one then has to compress that very large DR into a very narrow DR. This is done by letting parts be exposed longer (burning) and parts be exposed shorter (dodging) during exposure of the photo paper. One does this by putting cut outs over the paper as masks.
Thank you, Wim. I see it better now. As far as I understand, the Zone System technique itself does compress the DR, what it does in the recording process is to "map" the tone of the scene onto the film (more or less) in a way designed by the photographer. So, when you say "Using Zone System techniques it is possible to get 15-16 stops recorded at about 10 stops (or less) on film" I guess you also mean using the GND filters to compress the DR. Am I right?
So, if GND filters (or digital HDR) are used, the DR that can be recorded by films/sensors are extended. Without these DR compression techniques, the "intrinsic recordable DR" of modern digital sensors indeed already exceeds the "intrinsic recordable DR" of even B&W films, if I understand your comments correctly.
Best regards,
Frank
[/quote]
Mr Adams did not get 15-16 EV from 10EV film. He used black and white film, which (depending on which type/brand/era) will have upto 14EV. But that 14 (or 10 or whatever) EV is what can be measured after development. and that is then at a set development time. After the development, that is than that. No way to get more DR in post processing. However, Mr. Adams did something quite particular during development of the film. He used large format cameras, so he had large format negatives. He developed parts of one negative in different durations. So, lighter parts in the photo he let develop for a different time than darker parts. This then resulted in the film showing highlights darker than with normal development and deep dark lighter than with normal development, extending the DR.
In post processing (putting that negative as positive in print on paper) one then has to compress that very large DR into a very narrow DR. This is done by letting parts be exposed longer (burning) and parts be exposed shorter (dodging) during exposure of the photo paper. One does this by putting cut outs over the paper as masks.