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Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Thu Jan 02, 2020 1:19 am
by jbradsh
I have your eos for efw adapter ("ZWO EFW-EOS for EFW and ASI1600) + mini-efw + 178 MMC.

I have tried attaching eos lenses and cannot get them to manually focus (my tamron 90mm does) and it appears looking on the internet that newer EOS lenses do not have a direct connection from manual focus wheel to focus mechanism (rather it controls the focus motor electrically) and so without an electrical connection to the lens at the time manual focus does not work. Your adapter has no electrical contacts.

I cant find anything on this support site about this so I assume people are having successes — am I missing something? Is there any ZWO workaround? (Except buying https://astromechanics.org/ascom.html)

(Yes, I have stabiliser and AF turned off on the lens.)
I have tried setting focus manually to infinity on a canon camera then moving it across to two gear but it didnt work. )
(I am trying to use a wide angle EOS lens — I have no other spacers in the link except those three components - lens / adapter / efw / asi178 - I presume this gives the right spacing from your manual diagram).

John Bradshaw

Re: Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Thu Jan 02, 2020 10:39 am
by Katherine.Tsai
This adapter does not support auto focus.

Re: Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Fri Jan 03, 2020 6:51 am
by jbradsh
I suspected that, It would be decent to have that in the description since it is almost impossible to buy manual focus lenses any more (except rokinin) and most of us would be expecting to use the canon lenses we have which if they are eos are pretty likely to be autofocus with a manual option that would be expected to work as such on an adapter for the purpose. :(

john bradshaw

Re: Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Fri Jan 03, 2020 12:12 pm
by Katherine.Tsai
Hi John,
I will convey your message to our devs.
Thanks for your feedback.
In astro photography we rarely use auto focus.:)

Re: Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Thu Jan 16, 2020 11:30 am
by James474789
jbradsh wrote:
Fri Jan 03, 2020 6:51 am
I suspected that, It would be decent to have that in the description since it is almost impossible to buy manual focus lenses any more (except rokinin) and most of us would be expecting to use the canon lenses we have which if they are eos are pretty likely to be autofocus with a manual option that would be expected to work as such on an adapter for the purpose. :(

john bradshaw
Most canon lenses work because they support full time manual focus. The STM lenses (which generally come bundled with the aps-c bodies) need power and do not therefore work.

Re: Manual focus doesn't work with EFW-EOS adapter unless there is power to the canon lens.

Posted: Tue Feb 11, 2020 7:20 am
by Katherine.Tsai
Sorry, we do not have that adapter.