Photographers can find a Leupold Base chart on the Leupold Optics website, www.leupold.com. A Leupold base chart is used to adjust the base of optical scopes on rifles and other firearms.
Although the Leupold bases are primarily made for firearm scopes, they are also used by photographers in digiscoping. Digiscoping is usually used for birding, animal watching and surveying land for hunters and hobbyists. In digiscoping, a long scope is mounted on a base to keep the camera still. Information about the Leupold Digiscoping Spotter Kit can be found on the websites of some photography clubs, such as the Los Angeles Silhouette Club.