Here you have a universal shutter-speed calculator that will allow you to calculate action stopping or blur producing shutter speeds for any film or digital camera. You simply have to enter the size in millimeters of the short side of the film or sensor into the 'Short Side' field. Always use the actual focal length of the lens for the calculations. You may also be interested in my Depth-of-Field Calculator and Field-of-View Calculator.
| 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 | |||
| Film Format Dimensions | |||||||||||
| Format | 35 | 645 | 6x6 | 6x7 | 6x9 | 4x5 | 8x10 | ||||
| Short x Long (mm) | 24x36 | 41.5x56 | 56x56 | 56x69.5 | 56x84 | 96x120 | 200x250 | ||||
| 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 | |||||||||||
| Millimeter/Inch Conversion | ||||||||||||
| Millimeter | 25.4 | 50.8 | 76.2 | 101.6 | 127 | 152.4 | 177.8 | 203.2 | 228.6 | 254 | 279.4 | 304.8 |
| Inch | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
Directions
Shutter Speed: To determine the shutter speed to use to stop action, enter your format's short side in the 'Short Side' field, lens focal length in the 'Focal Length' field, focusing distance in the 'Focus Distance' field, and the subject's speed in the 'Subject Speed' field. Click the 'Shutter Speed' button, and the calculator will show you the denominator of the shutter speed fraction needed to stop the action in the 'Shutter Speed Fraction 1/' field.
Print Blur: To determine how much print blur will be produced by a specific shutter speed for the format, lens, focusing distance and subject speed, fill in the appropriate fields and enter the denominator of the shutter speed in question in the 'Shutter Speed Fraction 1/' field. Click the 'Print Blur' button, and the calculator will show you the amount of blur produced in a print in which the short side of the format you are using is enlarged to 8". See more details below.
Details
Feet/MPH - Meters/KPH: When Feet/MPH is checked, the Focus Distance is in feet and the Subject Speed is in miles per hour. When Meters/KPH is checked, the Focus Distance is in meters and the Subject Speed is in kilometers per hour.
Subject Motion: The direction of the subject's motion in relation to the camera also determines how much blur you will see. The default for the calculator assumes that the subject is moving parallel to the camera's back (film plane). In other words, the subject would be moving directly from one side of the frame to the other as you look through the lens. This direction requires the fastest shutter speed to stop the motion.
Short Side of Format: The amount of blur you see in a print is determined by the speed of the subject, shutter speed, lens focal length, focusing distance, and degree of enlargement. The calculator's print size is based on enlarging the short side of the format to 8". For example, the short side of a 35mm or full frame digital camera format is 24mm. If your format has a ratio of 2:3, like 35mm, FX and many DX cameras, it would yield and 8"x12" print. If your format has a ratio of 3:4, like many consumer digital cameras, it would yield an 8"x10" print. The relative sharpness will appear about the same to you even with greater enlargements as long as you don't view the print from closer than its diagonal.
Print Blur: The default print blur is .5mm (one-half of one millimeter). This means that if you were holding the camera still while the subject moved through the frame, the shutter speed indicated by the calculator would allow the subject to move .5mm in an 8"x12" enlargement. The subject would appear frozen to most viewers.
• If you need the moving subject to be indistinguishable from a still subject shot with the camera on a tripod, you will have to use a print blur between .2mm and .25mm. However, if you try using those blurs you'll see that extremely fast shutter speeds are needed.
• Most photographers create more than a .5mm blur when they hand hold a camera at the suggested reciprocal of the focal length. For example, if you take a picture of an absolutely still subject and hand hold a 35mm camera with a 200mm lens attached at 1/200 of a second, you'll probably create more than a .5mm blur in an 8x12-inch enlargement.
• Print blurs between .5mm and .7mm will yield acceptably frozen subjects for most viewers.
• You can't use 0 as a print blur, but you can try .001.
• When you pan with the subject, the print blur of the subject will be less than indicated by the calculator. The background then blurs.
• For a totally blurred background when panning, enter a print blur number that is from half to the full length of the print. For example: an 8x12-inch print would have totally blurred backgrounds with print blurs from 152.4mm to 304.8mm.
Shutter Speed Fraction 1/: The number in the text block is the denominator of a shutter speed. For example, if 500 is in the block, it means 1/500 of one second.
If you want to calculate print blur using times greater than one second, divide 1 by the number of seconds you want to check and enter the result in this text block. For example, if you want to calculate print blur for a 2-second exposure: 1 divided by 2 = .5.
Shutter Speed Seconds: The number in the text block is the shutter speed in seconds. For example, .002 would be the same as 1/500 of one second. If you happen to use a very slow subject speed and a very large print blur, you will see full seconds in this text block. Try calculating a shutter speed for a 35mm format camera with a 50mm lens at 20 feet from a subject moving 3 MPH with a print blur of 200mm.
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