hyperfocal distance
& depth of field calculator

Select your Format
35mm (7 x 11 Print) 645 (8 x 10 Print)
6x6 (9 x 9 Print) 6x7 (8 x 10 Print)
6x9 (7 x 11 Print) 6x12 (6 x 11 Print)
6x17 (4 x 12 Print) 4x5 (8 x 10 Print)
5x7 (7 x 10 Print) 8x10 (8 x 10 Print)

These calculations are based on acceptable quality for the above print sizes, viewed from approximately 13 inches.
Enter the Focal Length of your lens
Enter an f-stop

Set your focus in feet to This is your Hyperfocal Distance.
Depth of Field extends from feet in front of your lens to infinity.
For calculations in meters click here.

Following are Hyperfocal Distance and Circle of Confusion calculations using standard 35mm format;

Since a normal human eye can resolve 5 lines per millimetre at a distance of 25cm, and the diagonal measurement of a 7 x 11 print (for an uncropped 35mm frame) is 330mm, then;

Diagonal of print in millimetres
Diagonal of film format in millimetres
x 5 = Resolution Factor

35mm film's diagonal measurement is 43mm, therefore the Resolution Factor = 38.372

Resolution Factor
= Circle of Confusion

The Resolution Factor enables us to calculate the Circle of Confusion of .026 for 35mm.

Focal Length 2

Circle of Confusion per Format x Aperture
= Hyperfocal Distance

The Circle of Confusion for 35mm is .026, so if your 35mm format lens has a focal length of 50mm and the aperture is set to f8, then the Hyperfocal distance is 12019mm (12 meters or approximately 39.4 feet).

So, if you're using a 35mm camera with a 50mm lens and you set your aperture to f8 and your focus to
39.4 feet (or 12 meters), subjects that are between half this distance (19.7 feet or 6 meters) and infinity,
will be acceptably sharp on a 7 x 11 print.

WebPage Copyright © 1998- G. Morris Photography