Your Camera’s Sensor Size when Photographing Dogs

By Kim Rodgers and Sarah Sypniewski from Dog Photography For Dummies

In order to make the most of your dog photography images, you should be aware of your digital SLR camera’s crop factor (sensor size). Although all digital SLRs have larger sensors than CDCs, not all digital SLRs have the same exact sensor size, and most have a sensor size that’s physically smaller than 35mm film.

The lenses that are used in digital photography are the exact same lenses that were created to be used with 35mm film, so when you pair these lenses with a new technology (digital photography) that sports a smaller-than-35mm-film sensor, it only records the middle part of the image coming through the lens that overlaps the sensor.

The overflow that runs off of the sensor (but that would have fit on 35mm film) is essentially cropped out — hence the term crop factor. The crop factor of your digital SLR (1.3x, 1.5x, 1.6x, and so on) is the multiplier that represents the ratio of how large the camera’s sensor is compared to the size of 35mm film.

For any given lens you purchase, the focal length (or angle of view that the lens is capable of) is perceived as being magnified when it’s paired with a cropped-sensor digital SLR camera because the sensor is only seeing part of the image.

Basically, all you need to know is that unless you buy a top-of-the-line, full-frame digital SLR camera with a price point upwards of $2,500, your digital SLR has a crop factor that you should always consider when buying a new lens.

The following image, for example, was photographed with a full-frame camera at a focal length of 17mm. If you take that same exact lens and put it on a camera with a 1.5x crop factor, the field of view in the final photo is narrowed to what you see within the pink dashed line.

Essentially, this means that wide-angle lenses aren’t as wide as you may think on your cropped-sensor camera. At a focal length of 17mm, your image looks as if it were shot at 25.5mm (17 x 1.5 = 25.5).

17mm, 1/100 sec., f/10, 1000

Having a cropped-sensor digital SLR isn’t a bad thing by any means; it’s just something to be aware of if you start purchasing various lenses.

Although CDCs technically have very large crop factors, CDC users don’t need to be concerned with them. CDCs don’t come with interchangeable lenses for starters, so whatever lens is paired with your CDC is what you’re stuck with. These lenses also already compensate for their extreme crop factors and are usually translated into 35mm-equivalent focal lengths so you’re not left doing the math.