extenders for ef-75-300mm

[luke]

i'm trying to find out the best solution to increase my telephoto capabiltiy for a ef 75-300, 1:4-5.6 lense, are there any compatable extenders, and if so what are the benefits? thank you

[ScottyP]

Check the forum on Photography On The Net (POTN).  There is a whole big sticky thread on there about how to circumvent the issue of no-autofocus-on-slow-lenses-with-teleconverters-mounted.  There were some folks that say a Kenko teleconverter (or at least some models) will not report itself to the camera, so the camera will continue to autofocus. 

Downsides include:

1.)  Image quality degradation by the TC,

2.)  Loss of a full stop of light on a 1.4x TC, and 2 full stops on a 2x TC,

3.)  Slower autofocus for sure, and

4.)  The possibility that the one you get won't do it the way some guy on POTN reports it did for him, and you have to return it.

Your image quality is likely to be quite poor if you can get that combo to work.  If you don't have $1,200 to spend on a 400mm f/5.6 lens, or thousands of dollars for a higher-end solution, consider buying a $420.00 "superzoom" (non-interchangable lens) camera to carry around for when you need the extra reach.  The SX 50 has the equivalent of a 1,200mm lens.  It will work pretty well in bright daylight, and the price is right.  Be sure to get a tripod with it for any shots in which you can't have a fast shutter speed; that kind of length makes it exceedingly difficult to avoid "camera shake."

[ebiggs1]

“... any compatable extenders, and if so what are the benefits? “

No, there isn't. They are not worth the money you waste on them. The Canon 1.4x is the only one I ever recommend and than only for it's specified lens'.

One exception I am experiencing is the Sigma 1.4x on the Sigma 50-150mm f2.8. I'll have to live with it for a while before I can actually recommend it.

[1611kjb]

Curious if you have found anything? I am using a Yongnuo YN Extender EF 2X III on my EF 70-200mm f/2.8L USM II and it works like a charm, as good or better than the Canon and 40% the cost (seems like less Chromatic Aberration at the edges). However, it won't work with the 75-300mm because it has those flat spots and the focal tube won't insert in the space (I'd just try cutting the space round so it would fit, but I'm sure I'd scratch the lens). I tried extension tubes but they also have been made with those flat spots (for no reason I can discern), so at worst I am looking for an extension tube with a round hole in the mounting so it will fit. I'd like to stretch it our to 600mm with a 2x.

'

[ebiggs1]

"I am using a Yongnuo YN Extender EF 2X III on my EF 70-200mm f/2.8L USM II and it works like a charm,..."

Depends on what your definition of "charm" is, I guess.