FD Teleconvertor to double your zoom?

[Peldor]

I have been looking around on Ebay and see FD Teleconcertor adaptor that doubles your zoom by attaching between the camra and the lens. I would think this would work but at the expence of sharpness and contrast (also you probobly would lose a few F stops. So what do you guys think? Anyone ever use somthing like this?

 

[Digital Matt]

Assuming you have a Canon with an FD mount, yes they work ok. Like you mentioned you will sacrifice something, but if you have really nice glass a TC is often very usable. I'm not familiar with Canon FD mount lenses and accessories, but many people use a 1.4x TC with the EF 70-200mm f/4 and f/2.8 and say there is no visible loss of quality.

 

[ksmattfish]

(also you probobly would lose a few F stops

You typically lose 1 stop with a x1.4 teleconverter, and 2 stops with a x2 teleconverter. Teleconverters are usually designed to work with focal lengths 200mm and greater. With a good lens and a good teleconverter image quality still remains very high.

I've seen photos (on the web, not prints) of a photographer who stacks 3 and 4 teleconverters together to get extreme focal lengths. I'm sure the manufacturers wouldn't recommend this, but I thought it was interesting.

 

[Peldor]

So with a canon 70-210mm zoom it would be ok to use a doubler if i take the Fstop loss into consideration?

 

[Digital Matt]

Yes and there's no need to keep the fstop loss in consideration, because the TC's maintain full ttl metering, although depending on what lens and camera you use, you may not have autofocus or IS.