Photography Calculators

Optics & depth of field

Depth of Field Calculator: Canon EOS R7 + Canon RF 70-200mm f/2.8 L IS USM

DoF is the band that looks acceptably sharp on a given print or screen. Plug the focal length on the barrel, the f-number you will shoot, focus distance and a CoC. If you focus at or beyond hyperfocal, the far mark is infinity — confirm with a test shot, not a live-view guess. This page is pre-filled for the Canon EOS R7 + Canon RF 70-200mm f/2.8 L IS USM (APS-C (Canon), 32.5 MP, 135 mm at f/2.8).

Inputs

Units
mm

Number on the barrel, not the 35 mm-equivalent printed on a crop body.

f/

f-number you will shoot, not the lens’s maximum.

m

Subject distance from the sensor plane. Imperial shows feet.

mm

≈0.030 mm full frame, ≈0.020 mm APS-C, ≈0.015 mm Micro Four Thirds.

Results

Hyperfocal distance
342.71m
Near sharp limit
2.98m
Far sharp limit
3.03m
Total depth of field
0.05m
Far limit is infinity
No

Yes when you are focused at or beyond hyperfocal.

Recommended gear

Calculation method

Hyperfocal H is f² divided by (f-number times CoC), plus the focal length, with focal length and CoC converted to metres. The near limit is focus distance times (H minus f) over (H plus focus distance minus 2f). If you focus at or past H, the far side is treated as infinity. Otherwise the far limit is focus distance times (H minus f) over (H minus focus distance), and total DoF is far minus near.

Exact formula

H = f²/(N·c)+f with f and c in metres. Dn = s(H−f)/(H+s−2f). If s≥H, far is infinity. Else Df = s(H−f)/(H−s), total = Df−Dn. Invalid if s ≤ f. Limits: Thin-lens, no focus breathing, no diffraction; CoC is a viewing convention, not a sensor spec; subject motion and focus-shift on zoom omitted.

Portrait vs landscape

At 50 mm f/1.8 and 3 m on full frame you have centimetres of DoF, not metres. Landscapes usually want hyperfocal or a focus stack. Portraits usually want the eyes in and the background out — do not chase a large total DoF number.

Live view lies

Magnified live view is not the same CoC as an 8×10 print. If the job matters, take a test shot at the taking aperture and check the file.

Frequently asked questions

Is this the distance on the lens scale?

It is distance from the sensor plane, the same reference EXIF uses. Barrel marks on old primes are close; many zooms are not. Tape the subject if the DoF is millimetres.

Why does far jump to infinity?

Once focus is at or beyond hyperfocal, the far plane of the CoC model is infinity. You still have a near limit. Stopping down does not magically sharpen a missed focus.

Which CoC should I use?

0.030 mm is the usual full-frame print convention. Pixel-peeping or a huge print wants a smaller CoC and will show less DoF. Pair this with the circle-of-confusion calculator if you are unsure.

Does crop factor go in here?

Not as a separate field. Use the real focal length and a CoC for that sensor. Putting a 35 mm-equivalent and a full-frame CoC on an APS-C body double-counts the crop.

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