A teleconverter lens, such as the ones Canon provides for their various lines of cameras, is a lens attachment that will extend the focal distance of the lens you are using. Since telephoto and zoom lenses can be very expensive, a much more cost-effective teleconverter lens will give you between 1.4x and 2x the focal distance to shoot subjects that are far away. When you have a teleconverter lens attached, there are several precautions you should take to avoid some of the attachment's drawbacks.
Use with Long Focal Length Prime Lens
You will get the best results from a teleconverter lens you use it with a prime lens that has a fairly long focal length to begin with. When using it with wide angle or zoom lenses, images tend to loose sharpness and quality.
Use a Tripod
A longer focal length will make any movement of the camera even more exaggerated, giving your blurry images due to the camera shaking. It is best to use a tripod when shooting with a teleconverter lens to give you a steady shot and a clear picture. At the very least, you should turn on the image stabilization setting in your camera.
Shoot with Good Light
When a teleconverter lens is attached, you camera will lose one to two stops, meaning less light enters the camera when taking a shot. This will limit your ability to shoot objects in low light. This will not provide a problem when shooting outdoors on a sunny day, but if it is cloudy or you are indoors, you may need to set up another means of lighting your subject.
Set Focus
With the loss of a few stops, your camera may not be able to use the auto focus function. Some cameras require an f-stop of at least f5.6 to use auto focus, so if you lose that stop when the teleconverter is attached, you will have to manually set the focus.
Avoid Shooting Into Light
Since a teleconverter magnifies your standard lens, it will also magnify any deficiencies in the lens, including chromatic aberrations and lens flares. Avoid shooting directly into light sources, as the lens flares produced may render the image useless. As a general rule, use the best lens possible with the teleconverter to get the best results.
Tags: teleconverter lens, auto focus, best results, focal distance, focal length, lens attached
