It is a method of taking photographs through the combination of a spotting scope and a digital camera.  According to a photography method called “collimation,” the digital camera photographs the images magnified by the spotting scope.  And unlike SLR cameras, digiscoped images will not blur due to mirror shock.

The focal length of a digiscope system is calculated by multiplying the focal length of the digital camera by the magnification of the spotting scope.  For example, when a 3X zoom digital camera with a 114mm focal length (35mm equivalent) and a 30X spotting scope are combined, the effective focal length will be 3,420 mm (114 x 30).  A digiscope system renders unbelievable focal lengths and super telephoto images.

If you have a spotting scope and a digital camera, you can try digiscoping right now.

Press the digital camera against the eyepiece of the spotting scope as shown in Fig.1 to the right (This is digiscoping).  Holding a camera to the eyepiece like this is difficult, images may be blurred and the alignment of the optical axes may be hard to obtain, but this will give you the general idea of what digiscoping is.

If you only have a spotting scope or digital camera take it to your local retailer of optical products to try out digiscoping.  You will quickly see the attractiveness of digiscoping and the telephoto images that can be achieved.

The most serious problem when digiscoping is “vignetting” (dark corners in the image).  “Vignetting” can sometimes be eliminated with the right combination of an eyepiece and a digital camera, but with some digital cameras the vignetting will not disappear.

To confirm the amount of vignetting a camera will have, hold the camera to the spotting scopes eyepiece as shown in Fig.1.  “Vignetting” may be reduced or eliminated by changing the eyepiece as shown in Fig.2 and Fig.3.