topic Re: Canon 300 2.8 stops focusing in EF & RF Lenses

Canon 300 2.8 stops focusing

smrooker — Tue, 10 Sep 2013 00:23:06 GMT

I have a used Canon 300 2.8 non is that I bought used. Tack sharp, great lens. But if you change from horizontal to vertical, it shuts off. in the repair shop now, they can't figure it out. any thoughts?

Re: Canon 300 2.8 stops focusing

ebiggs1 — Tue, 10 Sep 2013 14:13:05 GMT

Yes, send it to CPS.

Re: Canon 300 2.8 stops focusing

trulandphoto — Mon, 23 Sep 2013 16:52:56 GMT

Sounds like it might be a fault with the AF/MF switch or the wiring so that it is switching without you moving the tab. Canon service would be your best bet.

Re: Canon 300 2.8 stops focusing

TCampbell — Mon, 23 Sep 2013 19:21:04 GMT

Ouch... I happen to own one of these and can vouch for the fact that it is _not_ supposed to shut off AF when you rotate it.

If the shop can't figure it out... I'm wondering who you sent it to. Is this at a Canon repair facility??