A photographer determined to get the shot may overcome distance with a good telescopic lens. Also known as a telephoto lens, this camera attachment can capture distant subjects in detail. With a vast assortment of types to choose from, the photographer has to determine usual shooting needs. Comparing these requirements with lens capabilities, compatibilities, and magnifications is part of the solution. In addition, choosing the best telescopic lens involves size versus light transmission, stability, and price.
The telescopic lens draws objects closer, using the magnifying properties of curved optics. This type is also known as a telephoto lens and may be a fixed or zoom type; a zoom lens extends and retracts to adjust the rate of magnification. A good initial question is whether you would prefer to shoot wider or longer shots. With a 35 millimeter (mm) camera, a lens of 105 to 300 mm generally suits handheld shots; longer than this, and you may consider working with a tripod or image stabilization technology.
It's important to understand the maximum aperture you need. This will affect how much light can be processed through the tube, and whether flash would be necessary for more low light photography. A larger aperture usually provides more light and a shallow depth of field.
Another criterion is focal length. Ask yourself how far away and how large your subjects will typically be. This will allow you to choose a telescopic lens designed for optimal function at your preferred distances.
Consider whether you would prefer a zoom or fixed focal length telescopic lens. A zoom lens can offer versatility and fewer lens changes. The fixed focal length type, however, is faster. This might allow you to isolate subjects dramatically against a moving background.
Being faster than the zoom, the fixed length telescopic lens may better suit portraiture and moving photography. In contrast, a lens with multiple glass elements has a greater tendency to introduce lens flare. The more complex it is, the more versatility it may offer, and the more weight.
Additionally, a zoom lens constructed with multiple optics may be more prone to chromatic aberrations, or imperfections, than fixed lenses. With both types, sharpness plays a key role in performance. Degree of versatility combined with ease of operation will factor in. It's also useful to check manufacturer guides, reviews, and user reports to assess resulting image quality and performance before investing in an expensive lens. Weigh the balance between lens versatility, construction, and results, and shoot for distance.