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Messages 121 to 130 of 387 (Total: 387) First | Prev | Next | Last
Subject 
Author 
Date 
Re: Tricks and tips 
Barry Wilkinson  2:45 18 Jan 07 
Re: Tricks and tips 
Miles  5:34 18 Jan 07 
Re: Tricks and tips 
Jorge Gasteazoro.   17:56 17 Jan 07 
Re: Tricks and tips 
Steve Nicholls  18:18 17 Jan 07 
Re: Tricks and tips 
Jorge Gasteazoro.   18:20 17 Jan 07 
Re: Tricks and tips 
Steve Nicholls  18:48 17 Jan 07 
Re: Tricks and tips 
Jorge Gasteazoro.   19:14 17 Jan 07 
Re: Tricks and tips 
Miles  5:44 18 Jan 07 
Flare factor for "old" lenses. 
Steve Nicholls  22:18 6 Nov 06 
BTZS Exposure and Development Question 
Paul  10:53 19 Oct 06 
Hi,

I recently photographed a scene that raised an exposure question of two in my mind, and I am hoping that the wise BTZS users out there might share their thoughts.

The scene was an old condemned house in bright afternoon light. There were not any large or significant shadow areas, but I metered a shadow on the lawn just out of the frame since this appeared to be the same as the smaller un-meterable shadows under the roof line and beneath the wooden shingles that covered the side of the house. The difference between the low and high EVs indicated a SBR of 9. That was higher than I expected, but I metered it several times and each time I got identical results. So, I based my exposure on the shadow reading and indicated appropriate development. As an experiment I took another shot assuming a SBR of 7 since it “felt” like a 7 stop scene. (I simply took the high reading and subtracted 2 stops from it and took that as the new shadow reading and based the exposure on it). The film was TMAX 400.

I developed both negatives for the appropriate times (in this case 7.25 minutes for the SBR 9 neg and 11.5 minutes for the SBR 7 neg). I have not printed them yet, but both negatives look very good. However, the SBR 7 neg has slightly more contrast and looks to be the one that will print the best based on past experience. Still, the differences are subtle. My questions:

1. Given that Tmax 400 has a very straight line, shouldn’t it be possible to take two shots of the same scene at different exposures and get essentially identical negatives by developing each for the appropriate time? I realize that the shadow values will be different, but shouldn’t it be possible to get the highlights identical?

2. Would this not be a good way to test development times? I know for example that 11.5 minutes works well for scenes where the SBR is 7. If I shoot the same scene as a 7 and a 9, with adjusted exposure, would it be safe to assume that my development times for a scene with an SBR of 9 is dialed in when the highlights look (and print like) those of the SBR 7 neg?

Thanks,
Paul

 


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