Pass the towel, please.....

Another test shot, taken with a 500mm catadioptric lens (A.K.A. "mirror lens", "Reflex lens" or "Cat. lens") which uses mirrors instead of glass. These lenses are much smaller and lighter than the equivalent "normal" lens and they also cost a fraction of the price. They have a fixed aperture which is usually f8.0 (although the one used in this example is f6.3) and they have to be focussed manually. They provide a high magnification at a low(ish) price.... (Approx. £150-£200 / $233-$311) but they can be difficult to use without a tripod or other support, especially in poor lighting conditions. The resolution is not as good as the equivalent "normal" lens but they are much more convenient and will usually fit in a jacket pocket. This photo is not a great example of what these lenses can do as it was taken hand-held in dull weather conditions with the sensitivity turned up to ISO 400 to allow a faster shutter speed. In good lighting conditions, however, the results should be much better (see video below).

These lenses do not record most of the EXIF information (details below).

Camera: Nikon D300s
Lens: Samyang 500mm f6.3 catadioptric "mirror" lens.
ISO 400
Shutter speed 1/320 sec.

More information about these lenses & video here:
www.youtube.com/watch?v=6rRT6-aL6DM