Last Updated on January 23, 2022
Teleconverter & Extension Tubes – Beginner Guide
The teleconverter is a Lens?
The Teleconverter is a unique conversion lens which multiplies 2X, 3X the effective focal length of any SLR, DSLR lens. One end has a female mount to accept the camera lens, and the other a male mount to fit the camera body.
The Teleconverter doubles the effective focal length of the lens. In combination with a second converter, the effective focal length of the lens can be increased by 4X, 5X.
For example, when you have an F2.8/135mm telephoto lens, with a single converter you will have an F5.6/270mm lens. By the use of two converters, it becomes F11/540mm as well.
Read more: 3 Reasons To Use Vintage Lenses
How to Use the Tele Converter
- Remove the camera lens from the camera body.
- Mount the teleconverter on the camera body in exactly the same manner as required by the camera lens.
- Mount the camera lens, normal or telephoto, on the teleconverter just as though the teleconverter were the camera itself.
- Check that the meter coupling, on both camera and lens, is properly connected to the teleconverter.
- You should check both settings(converter and lens) before using in order to ensure the proper operation of the automatic feature.
- Once the converter and camera lens are properly mounted on the camera, focusing is accomplished just as normally would be the converter not mounted on the camera.
- The camera shutter speed should be adjusted in the same manner as before attaching the teleconverter. However, you should keep in mind that when the image is magnified by the teleconverter and lens combination, which also magnifies any movement in the camera(use the tripod and high shutter speed). This also applies to macro photography.
- To remove the teleconverter, first, remove the lens/converter combination (holding the converter) from the camera. Then separate the converter from the lens and refit the lens to the camera.
Fits directly between the camera body and automatic lens and maintains the fully automatic operation of any auto lens.
The diaphragm of the lens is synchronized automatically through the auto converter.
Fit between the camera body and a standard lens and provide a range of magnifications up to 1:1. In the same way as a teleconverter.
It increases the focal length of the prime lens, but it also provides an additional and variable extension for increased magnification.
Short Version of the Teleconverter
What is an Extension Tube?
An extension tube is a hollow, light-tight tube that fits between your lens and your camera mount. It comes as a set of 3 tubes of different lengths which singly or in combination makes it usable in 7 different lengths.
It moves your lens further from the camera, and the front element closer to the subject. The closer you can focus, the more magnification you get.
The Extension tube’s function is to provide an additional variable amount of extension between the lens and the camera body. This added extension becomes necessary when an increase in the focusing range of the camera lens is desired, as in close-up photography.
How to Attach the Extension Tube to the Camera
- Attach to the camera or detach in the same way as attaching or detaching the camera’s master lens.
- The tube set consists of various size tubes which may be used individually or in combination.
- With Nikon type of tube, be sure to attach master lens only after the tube has been properly attached to the camera body.
Compatibility of Lenses
- Suitable lenses are from standard to semi-telephoto as well as macro(micro) lenses.
- Wide-angle and zoom lenses are also suitable, but depending on how the lens is combined with the tube distance between the lens front and the subject may become extremely close.
Exposure and Shutter Speed when using Extension Tube
Exposure is determined by the proper combination of shutter speed and F stop. The shutter speed, of course, remains unchanged by the addition of the extension tubes, but the F value varies whit the amount of tube extension.
The F value(Aperture) of the lens is calibrated and is completely accurate only the lens is focused at infinity. With a tube, the lens is extended beyond the point at which exposure compensation can be neglected, making it necessary to apply the proper exposure correction factor.
Tips on using Extension Tube
- In close-up shooting, as the subject’s depth of field becomes shallow, never forget to stop down the lens.
- Take care that when the image magnification ratio increases camera shake is also liable to increase. The use of tripod or cable release is advisable.
- In the case of a TTL camera, the backflow of light from the viewfinder will have a stronger effect on light metering when the extension tube is attached than when shooting with the lens alone.
- The focus is adjusted by changing the distance between subject and camera.