Close-up lens

In photography, a close-up lens or close-up filter is a simple secondary lens used to enable macro photography without requiring a specialised primary lens. They work identically to reading glasses, allowing any primary lens to focus more closely.

Close-up lenses typically mount on the filter thread of the primary lens, and are manufactured and sold by suppliers of photographic filters. Some manufacturers refer to their close-up lenses as "diopters", after the unit of measurement of their optical power.

While some single-element close-up lenses produce images with severe aberrations, there are many inexpensive high-quality close-up lenses capable of producing excellent images; there is essentially no loss of sharpness when using these.

ee also

* Photographic filter#Diopters and split diopters

External links

* [http://www.imaginatorium.org/stuff/cufilter.htm What is a close-up filter?]