Bellows and Extension tubes for Digital SLR
Bellows and Extension tubes for Digital SLR | ||
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Those who own digital SLRs have all manner of accessories they can purchase to focus even closer. These all function by moving the lens farther away from the sensor, allowing you to reduce the distance between the subject and the lens. Bellows are accordion-like attachments that move along a sliding rail to vary the distance between lens and camera continuously over a particular range. Extension tubes are fixed-length tubes with a male lens mount on one end (to fasten to your camera) and a female lens mount on the other (to accept your camera lens). They provide a fixed amount of magnification but are commonly available in several different thicknesses. These extenders can produce sharper results than you get with close-up lenses, particularly when used with specialized macro lenses. The downside is that these attachments are expensive (as much as $100 or more) and reduce the light reaching your sensor by a factor of 2X to 4X or more (depending on the amount of extension). You'll probably have to make exposure readings in manual mode, too, unless you purchase a high-end extension tube set that couples to your camera's metering system. Unless you're taking a great many close-up photos, you probably don't need them. Extension On the CheapExtension tubes and bellows attachments for digital SLRs can be expensive. Some tubes may cost up to $160, as the newest kind that retains the autofocus and auto exposure capabilities of the macro lens. Bellows attachments can cost $300 or more. If you want to save a little money on these accessories, see if you can't pick up older non-automatic tubes intended for film cameras that use the same lens mount as your digital camera. An older bellows might be suitable for your new camera, too. Because close-up photography of non-living things usually proceeds at a slow and thoughtful pace, the need to focus and calculate exposure manually is not much of a disadvantage. Manual extension tubes can be purchased for a fraction of the cost of automatic tubes, and you can probably find a used bellows on eBay or at your local camera dealer. | ||