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| 1:1 image taken with Canon 30D and Canon EF 100mm f/2.8 Macro USM Lens |
The photo above was taken with a Canon macro lens on my Canon 30D camera. The size of the sensor on that camera is 0.59 x 0.89 in. Using a Canon 100mm macro lens set at 1:1, I was able to photograph about .85 in of the metal tape measure.
According to Canon USA, an image taken at life size records the subject at actual size on the film or digital sensor. "For example, if it has a diameter of 1 in., it will occupy 1 in. of your actual slide or negative. With a digital SLR, at 1.0x magnification, the image projected onto your camera’s sensor will likewise be the same size at the sensor plane as the actual subject itself."
This relationship is described as 1:1, because the subject is reproduced on the sensor or film at its original size.
The Photographic Society of America describes macro photography as life size (1:1) to 3 times life size (3:1).
In the photograph below, George Washington has been recorded on the Canon 30D sensor exactly the same size as he appears on the $1 bill.
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| 1:1 image taken with Canon 30D and Canon EF 100mm f/2.8 Macro USM Lens |
35mm film and full sized dslr sensors are 0.94 x 1.41 inches. Using the Uptons' definition, a close-up photograph would be of an object 9.4 x 14.1 inches or smaller.
Most non-professional dslr cameras have a sensor similar to the 30D - 0.59 x 0.89 in. By the Uptons' definition, a close-up taken with most dslrs would be of an object 6 x 9 inches or smaller.
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| 1/2 life sized image 1:2 image taken with Canon 30D and Canon EF 100mm f/2.8 Macro USM Lens |
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| 1/2 life sized image 1:2 image taken with Canon 30D and Canon EF 100mm f/2.8 Macro USM Lens |
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| 1/4 life sized image 1:4 image taken with Canon 30D and Canon EF 100mm f/2.8 Macro USM Lens |