Help! New EF 70-300 L wobbles

[dsiegel5151]

Also, Brian

[thekingb]

Well, I emailed Bryan Carnathan to ask if his copy wobbles too, and he told me that he would get back to me. He is a really nice guy. We are lucky to have this site.


Wobble notwithstanding, I still can't get over the IS and look forward to some outdoor shots tomorrow. Here's a shot (not a piece of art; just a bad conditions test shot) that I took handheld, at night indoors, ISO 1600, f/5.6 at 300mm and 1/15s shutter on my 7D. It's not perfect if you pixel peep at 100%, but 1/15s at 300mm on a crop sensor? That's pretty awesome.


I guess worst case scenario is that it goes back to B&H and I order another one.


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[piiooo]

...I tried it out and it worked the same; e.g., autofocus worked throughout the whole zoom range of the lens (this was done in the store too, so lighting wasn't good by any standard). So, I bought the Promaster and sent the Kenko back (they were optically identical on my 300 f4L IS). I checked online and there are some other threads noting that some of the Kenko teleconverters retain autofocus capability on greater than f5.6 lenses without taping on the semipro and below bodies. However, I don't think this is true for all of them, so if you are interested in this combination, I would go to a store and try it out. Kind of makes me want to rent a 400 f5.6 and try the autofocus with the cheap teleconverter combination.

Thanks a lot for the research and info.

My question is, if Kenko can make an optically decent teleconverter that works on any EF lens and retain decent autofocus at f6.3, why can't Canon?

I think HDNiteHawk's conspiracy theory applies here as well. Third party teleconverters clearly prove that it is feasible, but such thing would be against Canon's marketing.

[Todd Ovick]

Brian,


I was with a friend of mine today who had bought one these lenses and remembered your post.


I tried to wiggle or wobble the barrel that extends and it did NOT wobble. It seemed to be pretty firm.


hope this helps..


Todd

[btaylor]

Sounds like it might be a return job there Brian. That

[thekingb]

Thanks everyone for your comments. The lens is going back to B&H on Monday. After some shots today, I