Photography Calculators

Sensor & focal length

Angle of View Calculator: Canon EOS R5 + Canon RF 70-200mm f/2.8 L IS USM

This page is pre-filled for the Canon EOS R5 + Canon RF 70-200mm f/2.8 L IS USM (Full Frame, 45 MP, 135 mm at f/2.8). Crop bodies see a tighter angle than full frame on the same barrel.

Tight angle of view on the Canon EOS R5 + Canon RF 70-200mm f/2.8 L IS USM

135 mm on the Full Frame Canon EOS R5 (36 × 24 mm, crop 1) sees 15.2° × 10.2° (18.2° diagonal). Head-and-shoulders and compressed backgrounds; a crop body makes this barrel even tighter.

The Result is indicative and educational. It does not constitute a design, a technical opinion or medical advice and does not replace calculations or verification by a person with the appropriate qualifications and authorisations. Before purchase, installation or use in practice – in particular in electrical installations – the Result should be verified by a qualified specialist. Details: Terms of Service, point 4.

Inputs

Units
mm

Barrel focal length at the focus distance you will use.

mm

Active sensor width, left to right in landscape.

mm

Active sensor height. Flip these if you shoot portrait.

Results

Horizontal angle of view
15.19°

Left-to-right angle in degrees.

Vertical angle of view
10.16°

Top-to-bottom angle in degrees.

Diagonal angle of view
18.21°

Corner-to-corner angle, the number most lens specs quote.

The Result is indicative and educational. It does not constitute a design, a technical opinion or medical advice and does not replace calculations or verification by a person with the appropriate qualifications and authorisations. Before purchase, installation or use in practice – in particular in electrical installations – the Result should be verified by a qualified specialist. Details: Terms of Service, point 4.

Example products

Product links are Affiliate Links to Amazon websites. Using them does not cost you anything extra, and if you make a purchase we may receive a commission. Details: Terms of Service, point 5.

Calculation method

For a rectilinear lens the angle that a sensor dimension subtends is twice the arctangent of half that dimension over the focal length. Do it once for width, once for height, and once for the diagonal (hypotenuse of the sensor). A 50 mm on 36 mm-wide full frame is about 39.6° horizontal. Units of millimetres cancel; do not mix in crop factor on top of a crop sensor size.

Exact formula

α = 2 arctan(dim / (2f)) in degrees. Diagonal dim = √(w²+h²). Limits: Rectilinear thin lens; fisheye mapping, distortion, focus breathing and pupil shift omitted.

Cinema sensors

Open Gate, 16:9 and anamorphic desqueeze all change the recorded rectangle. Use the active pixel area in millimetres, not the stills full-sensor spec, if you are framing video.

Focus breathing

Unit-focusing primes and macros narrow at close focus — a unit-focusing macro at 1:1 sees only about half its infinity angle. Many internal-focus zooms do the opposite and shorten as they focus closer. Treat the infinity angle as a starting point and test at your real distance.

Frequently asked questions

Why is this narrower than the box says?

Ads quote diagonal on full frame, often at infinity. Close focus, a crop mode or an APS-C body all shrink the angle. Type the sensor you actually record.

Portrait orientation?

Swap width and height. ‘Horizontal’ then uses the short side of the sensor: a vertical frame is narrow from left to right and tall from top to bottom, so the vertical angle becomes the wider one.

Fisheye?

Fisheyes are not arctan. An 8 mm circular fisheye can see ~180° by design. This calculator will under-read; do not use it for fisheye coverage.

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