[Michael Piziak]

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My question about this system. See the image in the link at the end. In my reading, this is a historically technologically significant invention.
Question is, is that autofocus "thing" around the lens, is it apart of that lens, is it a part of the camera, or is it it's own device that one puts on the lens ?

https://en.wikipedia.org/wiki/Pentax_ME_F#/media/File:Pentax_ME-F.jpg

Addendum: link to it's historical significance:https://en.wikipedia.org/wiki/Pentax_ME_F

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Last edited by Michael Piziak; 01-19-2023 at 03:58 PM.

[pschlute]

Question is, is that autofocus "thing" around the lens, is it apart of that lens, is it a part of the camera, or is it it's own device that one puts on the lens ?

Hi Michael. The ME-F and the lens SMC- AF Zoom 35-70 2.8 had to be used together to get autofocus. The lens itself could be used on other cameras but would only autofocus with the ME-F. It was very revolutionary for the time....1981

There are a lot of batteries involved and they don't last very long ! I took this image with my ME-F and 35-70 autofocus lens almost 5 years ago.....

[pschlute]

This is the camera and lens.....

[Michael Piziak]

This is the camera and lens.....

Thanks.
So it is part of the lens.
I see them now sold on the auction site: SMC- AF Zoom 35-70 2.8 for sale | eBay

[bdery]

Yes, the AF "thing" is part of the lens. But that's misleading because the camera and lens have to be joined for AF to work. The lens won't focus on any other body

[TwoUptons]

I seem to recall there was going to be a 50mm of some flavor that autofocused as well, and the fact there was a f3.5 setting on the camera hints at probably a longer telephoto...

As an aside, there were several companies that made standalone autofocus lenses in the late 80s/early 90s.
I have a Vivitar 70-210 that will autofocus very happily when connected to nothing, and it works a treat on my K1000. It also works on the ME-F, which is a little weird...

The 35-70 lens is actually really good. I've shot with it on the K1 (in manual focus), and the results are quite good, though the ergonomics are a disaster.

The thing that's really impressive to me is that, as bad as the AF is on the ME-F by today's standards, if you look at the cameras that came out in the next couple of years, none of them were any better... it took getting to the next generation of AF (SF-1/X, N2020/501, EOS 650, Maxxum/Dynax 7000) for it to really be usable.

-Eric

[j0n4hpk]

Thanks, guys. I used to have one of those for a little while, but no 35-70mm AF lens.

[AsahiRaccoon]

Hi Michael. The ME-F and the lens SMC- AF Zoom 35-70 2.8 had to be used together to get autofocus. The lens itself could be used on other cameras but would only autofocus with the ME-F. It was very revolutionary for the time....1981

There are a lot of batteries involved and they don't last very long ! I took this image with my ME-F and 35-70 autofocus lens almost 5 years ago.....

That's a very nice shot!

---------- Post added 02-03-23 at 11:52 PM ----------

This is the camera and lens.....

Wow! That's what I would call "pristine condition".

---------- Post added 02-03-23 at 11:56 PM ----------

My question about this system. See the image in the link at the end. In my reading, this is a historically technologically significant invention.
Question is, is that autofocus "thing" around the lens, is it apart of that lens, is it a part of the camera, or is it it's own device that one puts on the lens ?

https://en.wikipedia.org/wiki/Pentax_ME_F#/media/File:Pentax_ME-F.jpg

Addendum: link to it's historical significance:https://en.wikipedia.org/wiki/Pentax_ME_F

From what I have read on the Internet, the ME-F uses TTL in-body contrast detection AF. The AF motor though is not on the body but the lens, hence you put AAA batteries in it to power the motor and hence you got an electronic range-finder when you mount anything but the dedicated KF mount 35-70 f2.8 on the ME-F (providing you have an aperture ring on the lens and the speed of the lens is within the AF detection capabilities.

[Bbsteinle]

I believe the ME-F provided focus confirmation with regular K-mount lenses, hence the switch on top by the rewind crank for inputting maximum aperture.