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How do I calculate the aperture size and area You divide the focal length by the aperture/F-stop value. Infact, that's what the F-stop/aperture value is. It's a divider. Sometimes written as ƒ2.8 (as an example) but a lot of people leave out the vinculum and should be written as ƒ/2.8. Replace the ƒ with the focal length and that's the diameter of the ...


Your lens is a 35/2.8, but that doesn't mean the aperture is necessarily f/2.8. Just that f/2.8 is the widest it can be opened. The f-number is the focal length divided by the aperture diameter: f_number = focal_length / diameter So, solving for the diameter: diameter = focal_length/f_number. So, in this case your diameter is 35mm/2.8 = 12.5mm. If the ...


The aperture size is a property of the lens only and does not depend on the crop factor. It does depend, however, on the actual focal length of the lens (not the "equivalent" focal length). So you need to obtain the actual focal length by dividing by the crop factor. You can then calculate the size (diameter) of the aperture (strictly speaking the size of ...


So, it helps to start with knowing what a "stop" means. See What is one "stop"?, but, fundamentally, each stop is a doubling or halving of the exposure. So, given two shutter durations, you can find the number of stops between them by calculating the binary logorithm (log₂) of each, and subtracting. (If you don't remember your elementary school ...


For the standard set of shutter speeds (1 sec, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000), divide the higher shutter speed by the lower, and round to 0 decimal places if necessary. If the result is 2, it's 1 stop. If it's 4, two stops. If it's 8, three stops. If it's 16, 4 stops. See the pattern? If the shutter speed falls between ...

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