Basically the change of focal length is only considered as a change of angle of view. APS-C sensor has a crop factor of 1.6 of the full frame sensor. ie Anything viewed with the APS-C sensor will be cropped 1.6 times the Full frame sensor. Hence 300x1.6 = 480 mm. Crop factor just means that for a certain focal length the fov on an APSC camera is identical to having a lens with 1.5x that focal length on a full frame camera. It has nothing to do with whether it's a full frame lens or an APSC lens. An APS-C 200mm will have identical fov to a full frame 200mm. The only difference with an APS-C lens is the An APS-C size sensor measures 25.1mm × 16.7mm and consequently has a diagonal measurement of 30.1mm. That’s significantly smaller than the full-frame sensor’s diagonal (43.2mm). If you use this lens on a full-frame DSLR, the corners will be left unexposed and therefore appear very dark. The only change comes when you mount a APS-C lens on a full frame body or vice versa. It seems like people on the internet are confused and and keep saying APS-C lenses have a 1.5 crop ratio vs Full Frame, so for instance a 50mm APS-C lens has less a field of view compared to a 50mm Full frame lens.. but they are the same. The corrected forumula is: FOV (rectilinear) = 2 * arctan (frame size/ (focal length * 2 * (m+1) )) Where "m" is magnification. At infinity m=0, so the first formula applies. A 50mm lens focused at infinity has a horizontal field of view of about 39.6 degrees for a full frame 35mm camera. p5aDVr. So this lens on an APS-C camera will have the same field-of-view as a 52.5mm lens on a full-frame (i.e, 135 format or 35mm - don't get confused with the format being the same as the focal length - it's just a coincidence) camera. Well, the first answer is that the focal length on the 36×24 camera is double the focal length of the m4/3 camera (50mm vs 25mm) so the full frame camera requires more light to get the same exposure on its larger sensor. That’s why the virtual aperture is larger. This also helps us explain why we have f-stop numbers in the first place. A zoom lens lets you use a variable focal length. The Canon EF 70-200mm f/2.8L IS III USM is a zoom lens. It lets you work at a focal length of 70mm, 200mm, and anywhere between. A prime lens operates with a fixed focal length and low aperture value. For example, an 85mm, f/1.8 lens has a focal length of 85mm and an aperture of f/1.8. 3 days ago · The G1 X Mark III packs a 24.2MP APS-C sensor, but unlike the fixed focal length Fuji and Ricoh APS-C cameras on this list, Canon’s top-line compact stands out by sporting a 3x 24-72mm-equivalent zoom lens. The f/2.8 max aperture is also impressive, but that’s only at 24mm - by 72mm it’s shrunk to a more modest f/5.6. To find the equivalent angle of view for a lens on a crop sensor body, simply multiply the magnification amount by the focal length of the lens. The two most common crop sensor sizes are APS-C and Micro Four Thirds, which have a 1.6x and 1.5x crop factor respectively.

full frame vs aps c focal length