85mm f1.2L II and 40mm f2.8 focus by wire

[symmar22]

Hello, just a simple question, about the focus by wire. If I got it right, it means that you can only manual focus the lens when the camera is powered and metering, right ?

So it means that as soon as the metering goes off, you can't focus manually any more until you half press the shutter again?

Do you know any other lens than the 85mm 1.2L (II) and the 40mm f2.8, who share the same focus by wire mode ?

I was about to buy the 40mm but this is an absolute NO GO for me, since I use manual focusing a lot. Any information would help....

 

[Loswr]

Yes, that's correct.

I expect it applies to the new EF-S 18-135mm f/3.5-5.6 IS STM lens as well, since it has the same type of AF motor as the 40mm f/2.8 pancake.

There aren't any other current lenses with electronic manual focus (aka focus by wire), but some of the older lenses, including a few of the superteles like the 500mm f/4.5, also had it.

 

[symmar22]

Thanks Neuro for your fast reply, do you confirm both 85mm 1.2L (I & II) use the focus by wire system ?
What about the new 24 and 28 IS ?

 

[Loswr]

The 85L I and II are both electronic MF. The new 24mm and 28mm IS lenses have regular USM AF, including full time manual focus.

 

[symmar22]

Many thanks for the explanation