Crossing a microscope with a camera gives you a micrograph, a tiny photograph that allows artists and scientists to show the beauty inaccessible to the naked eye. Every year the Small World competition run by optics giant Nikon celebrates this hidden world. This year the winners range from an anglerfish ovary to the sex organs of plants via a rusted old coin.

Heiti Paves of the Tallinn Institute of Technology, Estonia, won the competition with this image of a thale cress (Arabidopsis thaliana) anther magnified at 20x. The thale cress is an important species used in the study of plant genome traits. It made history in 2000 when it became the first plant to have its entire genetic code sequenced and now stands as a model species for understanding the molecular biology of many plant traits.

This section of flower stem from a spiny sowthistle was photographed by Gerd Guenther of Dusseldorf, Germany. Guenther used a "dark field" microscopy technique whereby the sample is illuminated, but only light that is scattered by objects will reach the camera. This gives a brightly lit sample contrasted against a black background.

Working at the Institute for Microstructural Sciences in Ottawa, Canada, Pedro Barrios-Perez took this image of a wrinkled photoresist – a photolithographic emulsion used in semiconductor manufacture. This image was captured at a magnification of 200x using a "bright field" technique whereby the object is illuminated from below and observed from above. Barrios-Perez also entered the competition in 2008, gaining an honourable mention for another image of a photoresist.