Here you have a universal depth-of-field calculator and a learning tool for your photography. The two rows allow you to make immediate comparisons between lenses and formats, and to see how focal length, focusing distance, circle of confusion, hyperfocal distance and subject magnification relate to depth of field. You may also be interested in my Field of View Calculator and Shutter Speed Calculator.
| Film Format Dimensions | |||||||||||
| Format | 35 | 645 | 6x6 | 6x7 | 6x9 | 4x5 | 8x10 | ||||
| Short x Long (mm) | 24x36 | 41.5x56 | 56x56 | 56x69.5 | 56x84 | 96x120 | 200x250 | ||||
| Some Digital SLR Dimensions | |||||||||||
| Format | Nikon APS-C |
Canon APS-H |
Canon APS-C |
Fuji APS-C |
Sony APS-C |
Sigma Foveon |
Pentax APS-C |
Olympus 4/3 |
|||
| Short x Long (mm) | 15.8x23.6 15.6x23.7 |
18.7x28.1 | 14.8x22.2 15x22.5 |
15.5x23 | 15.7x23.5 | 13.8x20.7 | 15.7x23.5 15.6x23.4 |
13x17.3 | |||
| Compact Digital Dimensions | |||||||||||
| Format | 1/3.6" | 1/3.2" | 1/3" | 1/2.7" | 1/2.5" | 1/2" | 1/1.8" | 1/1.7" | 2/3" | 1" | |
| Short x Long (mm) | 3x4 | 3.42x4.54 | 3.6x4.8 | 4.04x5.37 | 4.29x5.76 | 4.8x6.4 | 5.32x7.18 | 5.7x7.6 | 6.6x8.8 | 9.6x12.8 | |
| from Wikipedia "Image Sensor Format" article | |||||||||||
| Decimal/Inch Conversion for Feet Calculations | |||||||||||
| Decimal | .083 | .167 | .25 | .333 | .417 | .5 | .583 | .667 | .75 | .833 | .917 |
| Inch | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| f/stop Chart | |||||||||||||
| Full | 1 | 1.4 | 2 | 2.8 | 4 | 5.6 | 8 | 11 | 16 | 22 | 32 | 45 | 64 |
| Third | 1.12 | 1.58 | 2.25 | 3.18 | 4.49 | 6.36 | 8.99 | 12.71 | 17.98 | 25.43 | 35.95 | 50.84 | 71.91 |
| Half | 1.19 | 1.68 | 2.38 | 3.37 | 4.76 | 6.73 | 9.51 | 13.45 | 19.03 | 26.91 | 38.05 | 53.81 | 76.11 |
| Third | 1.26 | 1.77 | 2.52 | 3.56 | 5.03 | 7.12 | 10.07 | 14.23 | 20.14 | 28.48 | 40.27 | 56.95 | 80.55 |
| Full | 1.41 | 2 | 2.83 | 4 | 5.66 | 8 | 11.31 | 16 | 22.63 | 32 | 45.25 | 64 | 90.51 |
| bottom row shows true f/stop numbers for f/stop at top of next column | |||||||||||||
Directions
Depth of Field: To calculate depth of field, choose feet or meters, 35mm/FX, APS-C/DX or a custom circle of confusion for other formats (see below), enter the lens focal length, f/stop and focusing distance in the corresponding fields and the calculator will provide you with near, far and total depth along with the hyperfocal distance and subject magnification when you click the button.
f/stop-Focus Distance: To calculate the f/stop and focusing distance for a specific depth of field and lens combination, choose feet or meters, 35mm/FX, APS-C/DX or a custom circle of confusion for other formats (see below), enter the lens focal length, near and far depth you want to keep in focus, and the calculator will provide you with the f/stop and focusing distance to use along with the hyperfocal distance and subject magnification when you click the button.
Details
Feet, Meters: Choose feet or meters. Default is feet.
ROW 1, ROW 2: This is where you set the format or circle of confusion you want to evaluate in the corresponding rows below. Choose 35mm/FX, APS-C/DX or a custom circle of confusion. The default is for the APS-C/DX format and an acceptable maximum circle of confusion of .017mm, which will work fine for all APS-C sensors. See instructions below to use the calculator with other digital and film formats.
Focal Length: Enter the actual focal length of the lens to be evaluated.
Lens f/stop: The f/stop number to be evaluated or to use.
Focus Distance: The distance from the front of the lens to the subject. This is actually supposed to be the front nodal point, which isn't the very front of the lens, but a little behind that. For most applications, the difference isn't important.
Near Depth: Distance from the front of lens to the nearest area to be in focus.
Far Depth: Distance from the front of lens to the farthest area to be in focus.
Total Depth: Distance from near depth to far depth.
Hyperfocal Distance: Focusing distance that will provide the greatest depth of field for the focal length and f/stop combination being evaluated. Everything from half that distance to infinity will be in focus.
Subject Mag.: This is subject magnification. It is the size the subject would be on the film/sensor in relation to its actual size. For example, if Subject Mag. showed 0.1 the subject would record at 10% or one-tenth (1/10) its actual size. A 10-inch square would record as a one-inch square on the sensor. It is not a necessary part of a depth of field calculator. I put it there as a learning tool when you are making comparisons.
Custom CoC
To use the depth-of-field calculator with a format other than 35mm, FX or DX, enter the short side of the format in millimeters in the Circle of Confusion Calculator. For example, the format for 35mm film is 24mm x 36mm. You would enter 24 in the calculator to find the circle of confusion to use. You will find some film and digital formats listed in the charts.
The Standard CoC is fine for general picture taking, especially if you seldom make prints larger than 8" x 12". It would still work fine for larger prints as long as you viewed them from no closer than the diagonal of the print.
The Critical CoC would probably be more appropriate if you regularly make prints larger than 8" x 12", especially if you intend to view them up close or if you regularly crop your pictures. You will see a little more detail at the near and far limits of depth.
The default CoC for the calculator 35mm/FX and APS-C/DX formats is for critical use.
You can use the calculator to compare the computed results from the critical and standard CoC numbers and then run some tests with your own equipment to decide which works best for you.
You can find a little more information about circle of confusion here.
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