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02-07-2014, 06:44 PM   #1
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Anti-shake focal length settings

When you guys set the focal length on non-AF lenses, do you use the engraved focal length of your lens or the cropped, 1.5X, focal length? For example, you mount a 50mm Pentax-M prime... do you set the focal length to 50, or its cropped equivalent of 75mm?

Not a trick question. I would have set it to 50mm, but it occurred to me I was wrong once.

02-07-2014, 06:51 PM   #2
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The camera makes the required conversions of motion magnification. Set the NR to the focal length on the lens. If you use 300 when the lens is 200, you will cause motion blur as the camera over corrects.
02-07-2014, 08:08 PM   #3
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FL is a lens characteristic and got nothing to do with the camera body. In short a 50mm is a 50mm no matter if it's on a mini-sensor, large format, laying on the table or when you look through it with the lens.
02-08-2014, 09:20 AM   #4
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QuoteOriginally posted by VisualDarkness Quote
FL is a lens characteristic and got nothing to do with the camera body. In short a 50mm is a 50mm no matter if it's on a mini-sensor, large format, laying on the table or when you look through it with the lens.
True enough, but the apparent motion on the output from a 16x24mm sensor is 150% of the apparent motion at a given output size from the 24x36 sensor. This is not because of the lens, the camera body or sensor size, but because of the increased magnification of the output product, printing a 24x16 inch print from 35 mm film, requires magnification of 16x; to print from APS-C the magnification is 24x. The apparent size of the shake is greater on the output from the smaller sensor.

02-08-2014, 09:26 AM   #5
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Wouldn't just lo love to meet the guy that came up with the concept of "crop factor" or "35mmm equivalent" and string him up by his thumbs?
02-08-2014, 09:44 AM - 1 Like   #6
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QuoteOriginally posted by Parallax Quote
Wouldn't just lo love to meet the guy that came up with the concept of "crop factor" or "35mmm equivalent" and string him up by his thumbs?
Actually, it is not his thumbs that I would string him up by ....
02-08-2014, 10:29 AM   #7
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