Venus – X-Pro Vari-Length Auto Extension Tube
X-Pro Vari-Length AF Extension Tube (available for Canon and Nikon) is the world’s first extension tube with adjustable length from 40mm to 56mm. Users could adjust across different magnification by turning the ring on the extension tube.
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Extension tubes are designed to enable a lens to focus closer than its normal set minimum focusing distance. Getting closer has the effect of magnifying your subject (making it appear larger in the viewfinder and in your pictures). They are exceptionally useful for macro photography, enabling you to convert almost any lens into a macro lens at a fraction of the cost while maintaining its original optical quality.
The extension tubes have no optics. They are mounted in between the camera body and lens to create more distance between the lens and film plane. By moving the lens farther away from the film or CCD sensor in the camera, the lens is forced to focus much closer than normal. The greater the length of the extension tube, the closer the lens can focus.
Current extension tube in the market are mostly in 3 tubes with different lengths. Users have to uninstall and install a different tube in order to enjoy a different magnification ratio.
Core Features
– Adjustable length design allows users to enjoy different magnification without installing extra extension tubes
– Compatible with Canon DSLR cameras and EF mount lenses and is optimized to work with Autofocus lenses.
– designed with all the circuitry and mechanical coupling to maintain auto focus and TTL auto exposure with most Nikon lenses given there is enough light (at f/5.6 or brighter) to activate the cameras AF system properly.
– Internal patent-pending anti-flare coatings minimizes any optical impact by the tube
– Metallic housing with lightweight design for durability and longevity