Extensions vs. teleconverters

[Michael Bottoms]

Hi...
Though I've had some success with my photography over the years, I've never used extension tubes or teleconverters... I would like to extend my current longest lens--Canon 70-300 F4.5 (from memory). Can I use either of the above to increase my magnification? Can you suggest a product that is reasonable in cost, but will work with the Canon lenses. I have an EOS 20D. Thanks.
B:confused:

[Jon]

Are you hoping to focus tighter on close-in objects or to get "closer" to distant objects? Extension tubes and teleconverters have different purposes.

[Michael Bottoms]

I guess I hope to view distant objects up closer.

[Jon]

A teleconverter then; but Canon's and Sigma's won't fit your lens. Check out this sticky (http://photography-on-the.net/forum/showthread.php?t=41922).

[TomHuckWa]

I have the canon 2x tele, but it only works on my 70-200 f2.8 IS none of my other lenses. I use this combo on one of my 20Ds.

[runninmann]

If you own the Canon EF 70-300 f/4.0-5.6 USM IS, I believe you will be satisfied with the results from this lens paired with the Kenko Pro 300 DG 1.4X T-con. I used this combination and achieved acceptable results.

[Michael Bottoms]

Thanks to everyone...
A lot of information there... Sounds like this Kenko 1.4 might work for me... I'll investigate further
B