All converters screw on to an adapter, which, in turn, screws on to the camera body. Each lens has a lens power (i.e., 0.2x, 0.8x and 1.5x). When a converter lens is used with the on-camera lens, the combined focal length is the product of the lens power and the focal length of the on-camera lens. Recall that the on-camera lens has focal length in the range of 35mm and 420mm (35mm equivalent). If a 0.8X wide angle converter is used, the combined focal length is in the range of 28mm (=35mm×0.8) and 336mm (=420mm×0.8).
These converter lenses are of type * afocal. Parallel light rays entering an afocal lens are also parallel when they exit; however, the diameter of the exiting parallel light rays may be different from the diameter of the entering light rays. Thus, an afocal lens does not have focal length, or, its focal point is at infinity. As a result, afocal lens are only used for modifying focal lengths and other optical characteristics, and must be used with other prime lenses. This means afocal lenses are not supposed to be used alone.
Because converters are attached to the on-camera lens, creating a combined lens of modified focal length, the optical problems of the lens converter will be magnified by the on-camera lens. These include lens flare, ghost image, field curvature, aberration and so on.
These converter lenses cannot be mounted on to the camera directly. You will need appropriate adapter tubes. Click here for the details.
* Afocal - Describing an optical system in which an image is transferred without bringing it to a focus. Afocal photography, for example, involves pointing a camera, focused on infinity, into the eyepiece of a telescope whose image also appears at infinity. When an image is transferred as a beam of parallel light rays, the beam is termed an afocal beam.
| Wide angle Conversion
Lenses |
Fisheye |
0.2x |
0.38x |
0.45x |
0.5x |
0.6 |
0.66x |
0.7x |
0.75x |
0.77 |
| Bonica Wide angle Conversion Lenses |
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| Bower Wide angle Conversion Lenses |
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| Century Optics Wide angle Conversion
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| Epoque Underwater Wide angle Conversion
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| Ikelite Underwater Wide angle Conversion Lenses |
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| Intova Underwater Wide angle Conversion
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| Kenko Wide angle Conversion Lenses |
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| Lensbaby Wide angle Conversion Lenses |
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| Impact Wide angle Conversion Lenses |
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| JVC Wide angle Conversion Lenses |
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| Olympus Wide angle Conversion Lenses |
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| Opteka Wide angle Conversion Lenses |
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| Panasonic Wide angle Conversion Lenses |
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| Phoenix Wide angle Conversion Lenses |
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| Pro HD Wide angle Conversion Lenses |
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| Raynox Wide angle Conversion Lenses |
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| Sea & Sea Wide angle Conversion Lenses |
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| Sony Wide angle Conversion Lenses |
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| Sunpak Wide angle Conversion Lenses |
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| Vivitar Wide angle Conversion Lenses |
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| Conversion Lens Kits |
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| Conversion Lens Adapters |
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| Fisheye 0.2X |
Wide Angle 0.7X
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Wide Angle 0.8X
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Telephoto 1.4X
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Telephoto 1.5X
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Telephoto 1.7X
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Telephoto 2.2X
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| 7mm-84mm |
24.5mm-294mm |
28mm-336mm |
49mm-588mm |
52.5mm-630mm |
59.5mm-714mm |
77mm-924mm |
See Also
