Timeline for Why are f-stops not linear?
Current License: CC BY-SA 3.0
11 events
| when toggle format | what | by | license | comment | |
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| Jun 5, 2014 at 16:24 | comment | added | Kartick Vaddadi | Interesting. Thanks for the tip about off-camera flash, Michael. As someone who never uses flash, let alone an off-camera one, it's clear I have a long way to go :) | |
| Jun 5, 2014 at 5:15 | comment | added | Michael C | Most people who use it seem to think not, as no other system has caught on. And honestly, I don't think you can really consider yourself a photographer until you know how to use off camera flash. Until then you aren't creating images from light, you're just taking pictures. | |
| Jun 5, 2014 at 3:43 | comment | added | Kartick Vaddadi | Sure, but flash aside, wouldn't the proposed scale be easier? | |
| Jun 5, 2014 at 0:01 | comment | added | Michael C | @KartickVaddadi Which is much more complicated? Just memorizing the standard f-stop scale? Or memorizing the square root of every possible guide number for every possible flash? | |
| Jun 4, 2014 at 13:00 | comment | added | Kartick Vaddadi | So update the formula for flash guide numbers similarly. Change: guide number = distance x f-number to: guide number = distance x sqrt(f-number). | |
| Jun 4, 2014 at 11:57 | comment | added | Michael C | @KartickVaddadi "Needless to say, the formula to calculate exposure value in terms of F-number would be adjusted -- it would no longer square the F-number, since it's already squared." No it wouldn't with regard to flash guide numbers. | |
| Jun 4, 2014 at 4:33 | comment | added | Kartick Vaddadi | In case that was not clear, I am referring to the formula from en.wikipedia.org/wiki/Exposure_value#Formal_definition : exposure value = log base 2 (N^2 / t) where N is the f-number, and t is the exposure time. Now, with my proposed f-number, which is the square of the conventional f-number, the formula would change to log base 2 ( N / t). So the end result would be the same. | |
| Jun 2, 2014 at 12:32 | comment | added | Kartick Vaddadi | Needless to say, the formula to calculate exposure value in terms of F-number would be adjusted -- it would no longer square the F-number, since it's already squared. | |
| Jun 1, 2014 at 18:22 | comment | added | Michael C | Because then the same number would mean different exposure values at different focal lengths. | |
| Jun 1, 2014 at 3:51 | comment | added | Kartick Vaddadi | Thanks. My question was: instead of using the ratio between the focal length and the entrance pupil, why don't we use the square of this ratio? | |
| May 31, 2014 at 18:32 | history | answered | Michael C | CC BY-SA 3.0 |