mbroomfield
New member
I find it better (and simpler) to just use the long width of the image size to calculate FOV ratios between lenses and formats, even when changing format ratios (ie going from 2:3 to 3:4);
1) You don't "see" a diagonal FOV, you see it by the width of your image (different landscape to portrait of course)
2) Easy enough to do in your head
So to use your example;
35mm format width = 36mm
Shifted 4:3 width = 48mm
The FOV equivalent to using a 24mm lens unshifted on FF is
24*36/48 = 18mm
If you want to know what you'd get if doing a portrait
24*24/36 = 16mm
A little different due to the change in format ratio from 2:3 to 3:4
Hope this helps
1) You don't "see" a diagonal FOV, you see it by the width of your image (different landscape to portrait of course)
2) Easy enough to do in your head
So to use your example;
35mm format width = 36mm
Shifted 4:3 width = 48mm
The FOV equivalent to using a 24mm lens unshifted on FF is
24*36/48 = 18mm
If you want to know what you'd get if doing a portrait
24*24/36 = 16mm
A little different due to the change in format ratio from 2:3 to 3:4
Hope this helps
Ben,
I get the FOV equivalency by doing unsofisticated math. No scientists here.
If you’re shifting 12mm to each side, you get an image of 48X36 (4:3).
48X48= 2,304 +
36X36= 1,296 = 3600
Square root of 3600 = 60 (60mm is the image circle necessary for the capture)
We know the FF real image circle of 24X36 is 43.27
60 : 43.27 :: 24 : X
X = 17.3
17.3mm is the FOV equivalent for a 24TSmm lens when fully shifted.
If I’m mistaken, please anyone correct me asap. If there's a simpler way, I'd like to know it. Thanks.
Regards
Eduardo