What is a Teleconverter?
A teleconverter is a small optical device that is attached to your lens to reduce the ‘vignetting’ effect – the loss of sharpness at the edges of your image caused by the barrel distortion of most lenses.
It has three parts: a lens, a prism and an aperture control ring. The lens is the main part; the prism creates a virtual image of the subject and refocuses the image onto the camera sensor. The aperture control ring works like a ring on a regular lens to let you adjust the depth of field (the range of distances in front of and behind the focal point where objects appear to be sharp).
The teleconverter is normally used to extend the effective focal length of a lens. That means that by attaching it to the end of your zoom lens, you will be able to change the angle of view of the picture without actually changing the length of the lens.
For example, a 50 mm lens on a 35 mm camera body will produce a 35 mm film image, which is equivalent to a 75 mm lens on a 35 mm camera body. So, if you attach a 100 mm lens to a 35 mm body, you will be effectively using a 75 mm lens. This would mean that the picture you took will look similar to a picture taken with a 100 mm lens on a 35 mm camera body. In other words, you would be using the same focal length, but the angle of view will be smaller.
A teleconverter will not allow you to zoom, however it does provide a sharper image and makes the subject more clear. If you have a wide angle lens such as a 14 mm f/2.8 or 20 mm f/1.7, you can achieve the equivalent of 35 mm on a full frame camera (full frame = 36 × 24 mm). Teleconverters are available for many lenses including the standard 28 mm, 50 mm, 70 mm and 105 mm.
Teleconverters are made in several different sizes. Smaller teleconverters are ideal for street photography as they add minimal depth of field and have a smaller size. They are usually suitable for 18–55mm focal lengths. Larger teleconverters are more useful for landscape photography and require a greater range of movement. They are usually available for 100–200mm focal lengths.
In addition to teleconverters, there are specialised lenses available for extreme close up photography. Some examples include a 1:1 macro lens, a 50 mm f/1.4 or a 85 mm f/1.8. They allow you to get closer to your subject, making details clearer and helping you create unique images.
For those who want to get creative with their photography, a teleconverter is a great option. If you are taking a landscape photograph, you may want to experiment with the new lens to see how it affects the overall look of the image. For those of us who like to take photographs of architecture, the teleconverter allows you to capture the cityscape more clearly and clearly.
Here’s how to attach a teleconverter to your lens:
First, attach the lens to your camera body. Then, screw the attachment ring on to the end of the lens. Then turn the aperture control ring so it is facing away from you. At this stage, the image should not be visible. Attach the teleconverter by turning it so that the prism faces towards you. The image of the subject should now be visible. Turn the aperture control ring to the position you want to use and take the picture. To remove it, reverse the process and remove the attachment ring, then unscrew the teleconverter.
If you want to use a different teleconverter, make sure you change the aperture control ring so that it is facing away from you before attaching it to the lens.