What exactly does a telephoto lens do on a camera? like this one= http://www.amazon.com/Opteka-Telephoto-F...
like this one= http://www.amazon.com/Opteka-Telephoto-F...
Answers:
A telephoto lens magnifies the emblem your camera sees and make it appear closer. It's like a telescope or two of a kind of binoculars for your camera. The picture your camera would ordinarily take is greatly magnified so you can both see more detail surrounded by it and you don't have to be as close to the be reluctant to get a righteous picture. Telephoto lenses come in handy, for example, when taking photos of animals at the zoo. Rather than getting a picture of the animal in the posterior of the enclosure, you can zoom surrounded by on its body or face.
The lens you hold linked to appears to be a straight telephoto next to a fixed magnification. You might want to consider a "zoom" type telephoto lens which allows you to vary how much you magnify the picture.
Magnifies things.
This is not a true telephoto lens as the term is conventionally used contained by photography; it is a telextender or teleconverter. Front-mounted teleconverters like this one are mounted within front of existing lenses and are low-powered telescopes specifically intended for use with cameras. Different models can change widely in price, resulting logo quality, size and mass, and magnifying power. There is a tradeoff among these features, beside the more powerful ones producing better image trait being bigger and more expensive.
This model have more magnification than most commonly available ones, which tend to be in the 1.4-2x array and is comparatively inexpensive for that much magnifying power. Before buying one, I would look for some preview images on the network using this device to see if the image competence and contrast is good satisfactory for your purposes.
It allows you to look resembling you're closer to the object than you in truth are... the one you're looking at is pretty cheap though! This isn't a true telephoto lens. A true telephoto lens essentially magnify the image and mounts onto the lens mount of a camera.
This is in reality a lens filter, because it screws onto an existing lens' filter threads and won't work lacking a pre-existing lens already mounted.
A lens filter like the one you allied to essentially acts approaching a little telescope. However, since this filter is essentially a cheap-add-on, it's predictable to have little or no coating to cut reflections from the lens elements. Moreover, it's a generic design, to work beside as many cameras as possible, so it won't pass you maximum sharpness or contrast like a true telephoto lens would.
This extra would essentially take your digital camera and magnify the image--like looking through a telescope--to produce it appear closer to the camera.
However, with a cheap model resembling this, you will typically see:
1) distortions.
2) chromatic aberrations (color fringing)
3) reduced sharpness
4) reduced contrast.
Hope that help.