Extension tubes - whats your say?

[Nabil-A]

I was just wondering what the general consensus is regarding extension tubes and their use in extending the focal length. Any opinions on when they are more useful than having a second lens alongs for example, money well spent, practical or rather combersome to use, image quality versus a dedicated telephoto lens etc.

At $500 or so australian dollars for the canon 2x extension tube, i can quickly see that buying a second lens is probably the better way to go.... but curious anyway as im probably missing something.

[LightRules]

Don't confuse ETs [extension tubes] with TCs [teleconverters]. It seems to me you are really referring to TCs because you mention "extending focal length". That said, looking at your current lenses in your sig, I wouldn't use a TC on those lenses. You should really use TCs only on excellent, longer teles, and best with long primes but do-able with good tele-zooms.

[Nabil-A]

no i was referring to tubes - extenders, not teleconverters

as seen here

http://www.centre.net.au/Canon_Extender_EF_2x_II_Lens_0007T3.html


not that im planning on getting one... but wondering what the go was..

[robertwgross]

This thing that you are looking at is a Canon 2x teleconverter. It is used only on some long Canon lenses for doubling the effective focal length of those long lenses. It will not fit on many lenses. In general, it costs two stops of light. This is not an extension tube.

An extension tube is more like a spacer that goes between any lens and the camera body. It has no glass in it. It acts by changing the effective close focus distance of the lens.

Those are two separate things and should not be confused.

---Bob Gross---

[thomascanty]

Like Bob said, that's a teleconverter not an extension tube. Also, it will not fit on any of the lenses you have listed in your signature.

[Nabil-A]

Like i said i was only researching what it was not looking to add a sophisticated L prerequisite item.

But thanks anyway.

[J.A.F. Doorhof]

Tubes are used for lowering your focus distance, for example to make macro more easy (getting your lens closer).
Extension TC's are used for getting more zoom distance, getting your OBJECT closer.

The canon TC's can't be used on anything other than Canon L lenses.
There are TC's from 3rd party suppliers like tamron/sigma etc. they work an almost all lenses.

Best is to use them on zooms with an aperture of f2.8 or maybe f4.0 above that you will loose AF.

[pturton]

no i was referring to tubes - extenders, not teleconverters

as seen here

http://www.centre.net.au/Canon_Extender_EF_2x_II_Lens_0007T3.html

not that im planning on getting one... but wondering what the go was..

Check the Teleconverter Frequently Asked Questions thread at the top of this forum.
http://photography-on-the.net/forum/showthread.php?t=41922

Canon calls their teleconverters "Extender" and the extension tubes "Extension Tube" which can lead to some confusion since everyone else refers focal length extenders as teleconverters (TC).

The Canon Extender EF 2x Mk II (teleconverter) works well with Canon's telephoto prime "L" lenses and will fit some "L" zooms as well but image degradation is considerable with the zooms.

Ocasionally I will use my 2x TC but more often I use my 1.4x TC which has less image degradation and only loses 1 stop of light.

Paul
http://www.iaw.com/~pturton/

[Nabil-A]

Thanks all,

I feel like such a noob considering the info was always under the EOS read first sticky....