What circle of confusion should I use?

It depends on the sensor size and on how the picture will be looked at, and the second half is what most tables leave out. The traditional values assume a print of a certain size viewed from a certain distance by someone with average eyesight — assumptions from an era of contact sheets and enlargers. A photograph examined at full magnification on a high-resolution screen demands a much smaller circle than the same photograph as a postcard. Scale the value with the sensor as a starting point, then tighten it if your pictures are going to be inspected closely, and treat every hyperfocal figure as approximate until you have checked one at the size you actually publish.

Is focusing at infinity ever better?

Yes, whenever the subject that has to be perfect is far away. Hyperfocal focusing trades a little sharpness at infinity for a lot of depth nearby, which is a good bargain when there is a foreground worth having and a poor one when the picture is a distant range of hills with nothing in front of it. It is also the wrong tool when the nearest interesting thing is closer than half the hyperfocal — no single focus point will cover both then, and the answer is focus stacking or a different composition rather than a smaller aperture that only adds diffraction.

The Hyperfocal Distance Is Only as Precise as a Judgement Call

Published 10/16/2026 · 4 min read · Image & design tools

Antonio Delgado — Traditions & pastimes writer at OneKitly

Symbolism · Calendars

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In short

The hyperfocal distance is where to focus so that everything from half that distance out to infinity looks acceptably sharp. It is the focal length squared, divided by the f-number times the circle of confusion, plus the focal length: a 50 mm lens at f/8 with a circle of 0.03 mm gives 10.47 metres, and focusing there keeps 5.23 metres to infinity in play. The third input is the problem. The circle of confusion is a decision about how much blur counts as sharp, not a property of the lens, and 0.02 mm is as defensible a choice for the same sensor as 0.03 — it just moves the answer to 15.68 metres. A figure quoted to the centimetre rests on a number somebody picked.

A 50 mm lens at f/8 gives 10.47 m — or 15.68 m if you tighten the circle of confusion from 0.03 to 0.02 mm. Both settings are defensible and they differ by half.

The focal length matters twice over

It is squared in the numerator, so halving it from 50 mm to 25 divides the hyperfocal by roughly four — 10.47 metres becomes 2.63. The aperture only appears once, so going from f/8 to f/16 merely halves it, to 5.26. That asymmetry is why landscape photographers reach for a wide lens before they reach for a small aperture: the wide angle buys depth of field at no cost, while stopping down buys it at the price of a longer exposure and, past a certain point, of diffraction softening the whole frame. The small residual difference between 2.63 and a clean quarter of 10.47 is the focal length itself, added at the end of the formula and mattering only at short focal lengths.

Err on the far side

The two ends of the resulting zone are not equally forgiving. Focus a little beyond the hyperfocal and you lose a small amount of the near limit while infinity stays comfortably sharp; focus a little short of it and infinity goes soft, which in a landscape is the one thing a viewer notices immediately. Since the number itself rests on a circle of confusion you chose, giving yourself that margin costs almost nothing and removes the entire risk. In practice: pick the value, focus slightly past it, and check the far edge of the frame at full magnification before moving on rather than trusting the arithmetic on a small screen.

Aperture

Hyperfocal distance, one variable at a time
Focal length	Aperture	Circle of confusion	Hyperfocal
50 mm	f/8	0.03 mm	10.47 m
50 mm	f/8	0.02 mm	15.68 m
50 mm	f/16	0.03 mm	5.26 m
25 mm	f/8	0.03 mm	2.63 m

Worked with our own calculator

Hyperfocal distance calculator

Given

Focal length (mm): 100
Aperture (f-number): 16
Circle of confusion (mm): 0.06

Result

Hyperfocal distance (m): 10.517

These figures are produced by the calculator below, not typed in by hand — they are recomputed whenever the tool changes.

Run it on your own figures →

Frequently asked questions

What circle of confusion should I use?: It depends on the sensor size and on how the picture will be looked at, and the second half is what most tables leave out. The traditional values assume a print of a certain size viewed from a certain distance by someone with average eyesight — assumptions from an era of contact sheets and enlargers. A photograph examined at full magnification on a high-resolution screen demands a much smaller circle than the same photograph as a postcard. Scale the value with the sensor as a starting point, then tighten it if your pictures are going to be inspected closely, and treat every hyperfocal figure as approximate until you have checked one at the size you actually publish.
Is focusing at infinity ever better?: Yes, whenever the subject that has to be perfect is far away. Hyperfocal focusing trades a little sharpness at infinity for a lot of depth nearby, which is a good bargain when there is a foreground worth having and a poor one when the picture is a distant range of hills with nothing in front of it. It is also the wrong tool when the nearest interesting thing is closer than half the hyperfocal — no single focus point will cover both then, and the answer is focus stacking or a different composition rather than a smaller aperture that only adds diffraction.

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