29th March 2004, 05:59 PM
Confusion of terms
I am a little confused with lenses such as "Sigma 70-300mm F/4-5.6 Super APO Zoom Lens". I mean zoom/tele and macro are like opposite characterisitcs of a lens. How is it possible that a single lens be described as both?
29th March 2004, 06:09 PM
macro describes the reproduction ratio of the lens. it often is related to how close the lens can focus as welll as the its focal length...
a zoom lens is a lens that can vary its focal length...eg 24-85 or 17-35... as opposed to 50mm or 85mm
i recon that 85mm would be considered medium telephoto, 200mm being telephoto and 600mm should be super telephoto.
so there can be a lens that has all the terms in one...
29th March 2004, 06:56 PM
Yup it's possible. A telephoto macro lens give you much more working distance from a subject to get the same degree of magnification as compared to a short macro. For example, (pulling numbers out of the air here), to get a 1:1 ratio for a 50mm macro lens, your working distance maybe 10cm. To get the same 1:1 ration for a 200mm macro lens, your working distance would be rough 4 times as much, to 40cm. This is of course, very useful out in the field when you are chasing butterflies.