Digiscoping

This Article Features Photo Zoom

One of the biggest challenges photographing wildlife is having enough magnification. You want to fill the frame and utilize all of the resolution of your digital SLR, but for most of us that means having an extreme telephoto lens, which can be prohibitively expensive.

With digital cameras has come the opportunity to engage in digiscoping, a different kind of extreme telephoto photography. Digiscoping involves using a spotting scope as an extension of a compact digital camera’s existing zoom lens or, through the use of an adapter, to attach a D-SLR to the scope. The spotting scope itself is a portable telescope designed for viewing terrestrial, instead of astronomical, subjects. Offering magnifications between 20x and 60x, these scopes deliver more magnification than would be available to a photographer with an SLR and an 800mm lens.

How It Works
A high-end compact camera often includes a powerful zoom lens, typically in the 6x to 18x magnification range, giving a 35mm equivalent of up to a 500mm lens in some cameras. While good, it’s not really enough for photographing a distant wildlife subject. When a 3x or 4x zoom camera is placed onto the eyepiece of a spotting scope with a 60x zoom, the magnification increases to as much as 180x, or a 9000mm lens!

With the high cost of an extreme telephoto, digiscoping can be a powerful, cost-effective alternative for wildlife photography.

Spotting scopes aren’t usually designed to be used for photography, but they still can produce excellent images. Features like multi-coated optics and exotic glass elements deliver images with high color accuracy and contrast.

Optical Zoom. Your camera’s optical zoom is the first consideration for successful digiscoping. All cameras, when set to their wide-angle setting and held up to the scope eyepiece, will show the scope image surrounded by a dark circle called vignetting. If the camera has a 3x or 4x lens, you usually can control the vignetting by zooming the camera lens until you can see that the corners are as bright as the center of the frame.

Filter Thread. Not all compact cameras have threaded lenses to attach the spotting scope. Other adapters are available for cameras without a filter thread. For example, many popular adapters use the camera’s tripod socket rather than the lens barrel for mounting, reducing stress on the lens assembly.

D-SLRs equipped with a fixed-power 50mm (Normal) lens work very well behind most spotting-scope eyepieces. Another option for D-SLR users is a made-for-photography adapter that allows direct mounting to a spotting scope. These systems provide higher functionality and image quality, but less overall magnification. When photographing flying birds and active animals, digiscoping with a D-SLR has the advantage of being better at following the action than trying to use the LCD screen of a point-and-shoot camera.

Choosing A Spotting Scope
There are several considerations when evaluating a spotting scope. The first is the size of the front element. Often ranging between 60mm and 80mm, the front element’s size impacts the scope’s light-gathering capability. The larger the front element, the more light it brings into the scope, resulting in a brighter image, especially under low-light conditions.

The eyepiece determines the level of magnification. Most spotting scopes feature a user-replaceable eyepiece. You can choose fixed-powered eyepieces from 20x to 60x or a zoom eyepiece such as a 20-60x. Although the zoom eyepiece gives the obvious advantage of adjusting the magnification at the turn of a ring, a fixed eyepiece features a wider angle of view. A wide field of view is beneficial when searching for a subject through the eyepiece. Too narrow a depth of field can make finding a subject incredibly difficult and frustrating. At these image magnifications, image shake is a key problem; use a sturdy tripod, a high ISO setting and a balance rail to help control blurry pictures. Typically, an in-camera image-stabilization system doesn’t work for digiscoping.

Digiscoping has been gaining popularity for years as a viable method for getting extreme telephoto compositions of small wildlife. Birders, in particular, have taken the process to a science and have been able to capture amazing images. If your budget doesn’t allow for the extreme telephotos some wildlife photography requires, consider a spotting scope as an alternative.