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Mr. Higgzbuffonton
!!Xsltv1VWxZT
>>240083 well, the math is fairly straight forward... from wiki, its about (focal length)f^2/(f-stop*CoC)...
CoC is -basically- (as far as is necessary to know) the size of a dot that is considered acceptably sharp.. For a 1.6x crop DSLR, this is about 0.018mm...
So, all you need now is focal length and f-stop.. since its focal lenght (squared) divided by f-stop*CoC, you could make a note of common f-stops times 0.018...
for example.. f/4 = 0.072, f/5.6 = 0.1008, f/8 = .144, f/11 = 0.198, f/13 = 0.234, f/16 = 0.288
you could just use that, but you'd need a calculator on the road when you decide on the exact focal length you want to use.. OR, you could take a lens, and write out the focal lengths and then divide that number by the numbers you got above^..
for example, I've gotten - 10mm, 12mm, 14mm, 17mm, and 20mm for one lens, and 18mm, 24mm, 35mm, and 55mm for another.
now from this you get, well, basically a chart like the above poster suggests, with your chosen values and chosen CoC size..
I only do this because all the charts I found had very specific focal lengths, all of which do not go lower than 17mm (I need 10mm, 12mm, and 14mm as I mentioned above)..
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