Here the first in a potential series of 'Mythbusters' dealing with topics of potential interest to photographers. :munch:
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Mythbuster "You have to expose for the shadows and develop for the highlights"
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Myth or Fact?
Let's follow Bill and Sam through a "Fred Picker Inspired" basic photography course to find out.
Both students load their identical, perfectly functioning cameras with identical TMY and shoot a series of test exposures, sharing the instructor's Pentax spot meter.. Bill listens closely to the instructor and makes a series of Zone I exposures at EI 6, 12, 25, 50, 100, 200 and 400.
Sam gets confused with the aperture dial, and makes a series of Zone VIII exposures at IE 6, 12, 25, 50, 100 and 200 and 400.
They develop their properly labeled film for 6 minutes in the same tank.
Bill listens to the instructor and zeros the densitometer on his "film-base-plus-fog" and identifies the frame that has 0.1 log more DENSITY. The frame he winds up with was the Zone I frame shot at EI 200.
Sam gets confused and zeros the densitometer to his FOGGED ( daylight-exposed) film base, then chooses the frame that has 0.1 log units more TRANSMISSION. The frame he winds up with was the Zone VIII frame shot at EI 12.
With their new exposure indexes, Bill (EI 200) and Sam (EI 12) both make some Zone VIII exposures on two rolls of film each. Sam gets confused with the aperture ring, however, and makes exposures that have eight stops LESS exposure (essentially Zone I). Both develop their properly identified film in the same tank for 6 minutes.
Bill and Sam head to the darkroom to test the development time. Bill places a piece of blank film-base-plus-fog into the enlarger and makes a test exposure. He identifies the first strip that is totally black and records the exposure.
He then places his Zone VIII exposure (shot at ei 200) in the enlarger and exposes it for the same time as indicated in his black test exposure. He covers 1/2 of the paper during the exposure. He processes the print and notices a totally white sheet of paper. He concludes his Zone VIII is too dense and makes a note to decrease development of the next roll by 20%.
Sam gets confused and places a piece of FOGGED (daylight-exposed) film base in the enlarger and makes a test exposure. He identifies the first strip that is totally white and records the exposure.
He then places what he thinks is his Zone VIII frame in the enlarger. It really is a Zone I exposure shot at EI 12. He gets confused and exposes 1/2 of his test paper to white light, then exposes the other half to his Zone I frame at the indicated time. He processes the print and sees a totally black sheet of paper. He remembers correctly the instructor saying that if there is no difference in the two sides of the test print then decrease development. He makes a note to decrease development of the next roll by 20%.
Bill and Sam take their second test roll that they had previously exposed above. They realize they are both decreasing development by 20% and the develop their properly identified film together in the same tank for 5.5 minutes.
Bill repeats his Zone VIII frame test and gets a test print that is half pure white and just begins to show some density on the other side. He concludes that his development is correct and he is ready to start shooting pictures.
Sam repeats his Zone VIII frame test (which he actually shot at Zone I) and gets a test print that is half pure black and is just slightly lighter on the other half. He remembers the instructors saying that if you can just barely see the difference in the two sides of the print that the development is correct. He concludes that his development is correct and he is ready to start shooting pictures.
The instructor stands outside in bright sunlight holding a gray scale. Both Bill and Sam photograph him at the same time with their tripods next to each other. Bill uses the spot meter to measure the shadowed face of the instructor and places it on Zone III at EI 200. He makes his exposure (1/200th at F16). Bill then checks the sunlight white shirt of the instructor and it falls right on Zone VIII. He concludes the scene should work well with the development time he had just established.
Sam gets confused and uses his spot meter to measure the sunlight white shirt of the instructor . He places the shirt on Zone VIII and makes his exposure at EI 12. His exposure is 1/12th of a second at F16. He then checks the shadowed face of the instructor and it falls right on Zone III, so he concludes the scene should work well with the development time he had just established.
Again they develop their properly identified film together for 5.5 min. and go to the darkroom to make their best prints. They both submit their best prints to the instructor, but they forget to put their names on the back of the prints.
They turn in their notebooks to the instructor and he sees that Sam got it all backwards. He EXPOSED FOR THE HIGHLIGHTS AND DEVELOPED FOR THE SHADOWS!
Obviously, the instructor would be able to tell which print was Sam's and which was Bill's.
Right?
(prints to follow...)
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Mythbuster "You have to expose for the shadows and develop for the highlights"
*****************
Myth or Fact?
Let's follow Bill and Sam through a "Fred Picker Inspired" basic photography course to find out.
Both students load their identical, perfectly functioning cameras with identical TMY and shoot a series of test exposures, sharing the instructor's Pentax spot meter.. Bill listens closely to the instructor and makes a series of Zone I exposures at EI 6, 12, 25, 50, 100, 200 and 400.
Sam gets confused with the aperture dial, and makes a series of Zone VIII exposures at IE 6, 12, 25, 50, 100 and 200 and 400.
They develop their properly labeled film for 6 minutes in the same tank.
Bill listens to the instructor and zeros the densitometer on his "film-base-plus-fog" and identifies the frame that has 0.1 log more DENSITY. The frame he winds up with was the Zone I frame shot at EI 200.
Sam gets confused and zeros the densitometer to his FOGGED ( daylight-exposed) film base, then chooses the frame that has 0.1 log units more TRANSMISSION. The frame he winds up with was the Zone VIII frame shot at EI 12.
With their new exposure indexes, Bill (EI 200) and Sam (EI 12) both make some Zone VIII exposures on two rolls of film each. Sam gets confused with the aperture ring, however, and makes exposures that have eight stops LESS exposure (essentially Zone I). Both develop their properly identified film in the same tank for 6 minutes.
Bill and Sam head to the darkroom to test the development time. Bill places a piece of blank film-base-plus-fog into the enlarger and makes a test exposure. He identifies the first strip that is totally black and records the exposure.
He then places his Zone VIII exposure (shot at ei 200) in the enlarger and exposes it for the same time as indicated in his black test exposure. He covers 1/2 of the paper during the exposure. He processes the print and notices a totally white sheet of paper. He concludes his Zone VIII is too dense and makes a note to decrease development of the next roll by 20%.
Sam gets confused and places a piece of FOGGED (daylight-exposed) film base in the enlarger and makes a test exposure. He identifies the first strip that is totally white and records the exposure.
He then places what he thinks is his Zone VIII frame in the enlarger. It really is a Zone I exposure shot at EI 12. He gets confused and exposes 1/2 of his test paper to white light, then exposes the other half to his Zone I frame at the indicated time. He processes the print and sees a totally black sheet of paper. He remembers correctly the instructor saying that if there is no difference in the two sides of the test print then decrease development. He makes a note to decrease development of the next roll by 20%.
Bill and Sam take their second test roll that they had previously exposed above. They realize they are both decreasing development by 20% and the develop their properly identified film together in the same tank for 5.5 minutes.
Bill repeats his Zone VIII frame test and gets a test print that is half pure white and just begins to show some density on the other side. He concludes that his development is correct and he is ready to start shooting pictures.
Sam repeats his Zone VIII frame test (which he actually shot at Zone I) and gets a test print that is half pure black and is just slightly lighter on the other half. He remembers the instructors saying that if you can just barely see the difference in the two sides of the print that the development is correct. He concludes that his development is correct and he is ready to start shooting pictures.
The instructor stands outside in bright sunlight holding a gray scale. Both Bill and Sam photograph him at the same time with their tripods next to each other. Bill uses the spot meter to measure the shadowed face of the instructor and places it on Zone III at EI 200. He makes his exposure (1/200th at F16). Bill then checks the sunlight white shirt of the instructor and it falls right on Zone VIII. He concludes the scene should work well with the development time he had just established.
Sam gets confused and uses his spot meter to measure the sunlight white shirt of the instructor . He places the shirt on Zone VIII and makes his exposure at EI 12. His exposure is 1/12th of a second at F16. He then checks the shadowed face of the instructor and it falls right on Zone III, so he concludes the scene should work well with the development time he had just established.
Again they develop their properly identified film together for 5.5 min. and go to the darkroom to make their best prints. They both submit their best prints to the instructor, but they forget to put their names on the back of the prints.
They turn in their notebooks to the instructor and he sees that Sam got it all backwards. He EXPOSED FOR THE HIGHLIGHTS AND DEVELOPED FOR THE SHADOWS!
Obviously, the instructor would be able to tell which print was Sam's and which was Bill's.Right?
(prints to follow...)
