Coupling ring (photography)
A coupling ring is used in photography to connect two lenses via their filter threads . This method is a cost-effective alternative to macro lenses in order to achieve comparable magnification scales .
If macro lenses are not one of the first purchases when setting up basic photographic equipment, macro images can be created in this way with two existing lenses and a relatively inexpensive coupling ring, and older manual lenses in particular can continue to be used. The lens attached in the retro position acts like a close-up lens , whereby the lens usually delivers better optical performance.
Some experiences and recommendations for macro photography with coupling rings are:
- Prefer fixed focal length lenses over zoom lenses
- Since the lens cannot be controlled via the camera in the retro position, you have to focus manually.
- If the opening of the retro lens is smaller than that of the lens on the camera side, vignetting is possible. The aperture should be opened to the maximum.
- The achievable image scale is the ratio of the focal length of the lens on the camera side to the focal length of the retro lens.
The coupling ring differs from the retro ring (reversing ring) in that it has two external threads for the filter thread of the lenses, while the retro ring has an external thread for the filter and a connection to the camera bayonet.
See also
Alternative equipment for macro photography:
- Macro lenses and magnifying glass lenses are special lenses for macro shots that are corrected for close-up areas
- Bellows and intermediate rings to increase the distance between the lens and the camera, so that the photographer closer to the subject approach can
- With retro rings (reversing rings) normal lenses can be connected to the camera upside down (with the front lens on the bayonet)
- Close-up lenses are screwed in front of the lens like filters and are another way of taking macro shots.