Yashica AF and Minolta AF

Discussion of lenses, brand or independent, uses and merits
Forum rules
No more than three images or three external links allowed in any post or reply. Please trim quotations and do not include images in quotes unless essential.
rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Yashica AF and Minolta AF

Unread postby rogprov » Sun Feb 01, 2009 6:41 pm

Digging through my old lenses I found one from when I had a Yashica AF230 many years ago. Looking at the mount I was surprised to see just how very similar it is to the MA mount. It is so close that I feel there must have been some collaboration between the companies over the design. Does anyone know the history?
Roger

PhotoTraveler
Grand Caliph
Posts: 245
Joined: Sun Aug 17, 2008 8:07 am

Re: Yashica AF and Minolta AF

Unread postby PhotoTraveler » Sun Feb 01, 2009 7:59 pm

They were basically rebadges with the aperture lever moved.

Peter Ganzel did a write up a while back on his Pbase.

User avatar
David Kilpatrick
Site Admin
Posts: 6220
Joined: Sat May 19, 2007 1:14 pm
Location: Kelso, Scotland
Contact:

Re: Yashica AF and Minolta AF

Unread postby David Kilpatrick » Sun Feb 01, 2009 8:31 pm

Pentax and Nikon both used very similar systems and so did Olympus - Minolta was the first, but until Canon devised in-lens focus motors, all AF systems used a motor in the body and a coupling drive to the lens.

The design of the coupling is based on the Hasselblad shutter-iris actuator or lens cocking connection. It's almost identical. That dates from the early 1950s. All Minolta did was to take a method for linking a drive shaft in a lens to a drive shaft in the body, which already existed in an unpatented or out of patent Hasselblad mechanism, and convert it for AF use. Since they did not invent this type of coupling, others then used it. I believe it had also appeared in a 35mm camera with focus control on a wheel on the body. The last new design ever to use the same method was the Contax G1, which used it for autofous and manual focus coupling. I'm not sure about the Hasselblad XPan and a few other specialist cameras.

David

PhotoTraveler
Grand Caliph
Posts: 245
Joined: Sun Aug 17, 2008 8:07 am

Re: Yashica AF and Minolta AF

Unread postby PhotoTraveler » Sun Feb 01, 2009 9:08 pm

In this case though it's not just similar design, but an actual modified A mount variant.

http://www.pbase.com/pganzel/image/82047034

rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Re: Yashica AF and Minolta AF

Unread postby rogprov » Sun Feb 01, 2009 9:45 pm

PhotoTraveler wrote:In this case though it's not just similar design, but an actual modified A mount variant.


Yes that was my point, they are so similar but not interchangeable . Nice comparison photo.
Roger

User avatar
David Kilpatrick
Site Admin
Posts: 6220
Joined: Sat May 19, 2007 1:14 pm
Location: Kelso, Scotland
Contact:

Re: Yashica AF and Minolta AF

Unread postby David Kilpatrick » Mon Feb 02, 2009 2:07 am

The Yashica 230AF looks very like a rebadged Minolta 7000/5000AF, but the mount is not so much more different than any other three-flanger bayonet (there are only so many choices, change the orientation, change the flange lengths, change the pitch of the electronic contacts, position of iris actuation etc). What I do not know is whether the flange to film distance was within the apparent range reported for the Minolta AF mount - nominally 44.6mm but measured by various people within 1mm either way, which is an excessive variation.

Since the camera was unconnected with the Yashica/Contax system and had a very short life, it's likely that Minolta had a hand in it - but that would not make sense given the plans they had for the AF system at the time. More likely, a third party contractor was involved, possibly the Chinon factory, in both systems. When the Club visited Japan in 1986, we were shown lens production at Sakai, but not shown camera production. Why? You would imagine camera production would be the main thing. Perhaps the 7000 and 5000 were actually assembled, even co-designed, with a third party plant.

David

PhotoTraveler
Grand Caliph
Posts: 245
Joined: Sun Aug 17, 2008 8:07 am

Re: Yashica AF and Minolta AF

Unread postby PhotoTraveler » Mon Feb 02, 2009 5:44 am

I was trying to find a write up pete did before, I think he found the ROM protocol/pinout was in fact the same, and they would physically mount, it was just the aperture re-location messing things up, and the registration was the same.

rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Re: Yashica AF and Minolta AF

Unread postby rogprov » Mon Feb 02, 2009 7:02 am

There was a series of Yashica AF cameras with this mount. AF200, AF230, AF270 and AF300 made between 1987 and 1994. There were slightly different names in various world markets. They were not re-badged from any another make. There were about a dozen lenses including independents.

Also a clever AF Converter 1.6x was made which enabled the use of Contax/Yashica manual focus lenses - and focussed many of them automatically. I think this would be interesting to some Minolta/Sony users if it could be modified to work with the MAF mount. Think of all those older Zeiss Contax fit lenses, Planar, Sonnar, Distagon, Tessar ….
Roger

User avatar
Dusty
Emperor of a Minor Galaxy
Posts: 2210
Joined: Thu Dec 18, 2008 5:04 pm
Location: St. Louis, Missouri, USA

Re: Yashica AF and Minolta AF

Unread postby Dusty » Mon Feb 02, 2009 7:26 am

rogprov wrote:Also a clever AF Converter 1.6x was made which enabled the use of Contax/Yashica manual focus lenses - and focussed many of them automatically. I think this would be interesting to some Minolta/Sony users if it could be modified to work with the MAF mount. Think of all those older Zeiss Contax fit lenses, Planar, Sonnar, Distagon, Tessar ….


There's a similar converter available for the Minolta MC/MD lenses that will mount it on A-mount bodies. The problem is you have a less quality optical element that degrades the quality overall, costs you an f stop and blows your focal length! Your fast 21mm 2.8 just became a 31.5mm 4.0, and if you use it on APS-C, it's not a 47mm lens. If I could get my hands on a cheap MD mount 200 or 300mm 2.8 MD lens, then I could accept the quality and speed loss to get L-O-N-G focal length fairly cheap.

In optics, there's just no free lunch.

Dusty
A couple of a350's, an a700 and now an a580, plus even more lenses.

rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Re: Yashica AF and Minolta AF

Unread postby rogprov » Mon Feb 02, 2009 7:43 am

There's a similar converter available for the Minolta MC/MD lenses that will mount it on A-mount bodies.
Dusty



Yes there are plenty of adapters available to fit various lenses to the MAF ... but the uniqueness of this Yashica one is that it auto-focusses manual focus Zeiss lenses ... must be interesting at the very least. :D
Roger

User avatar
Dusty
Emperor of a Minor Galaxy
Posts: 2210
Joined: Thu Dec 18, 2008 5:04 pm
Location: St. Louis, Missouri, USA

Re: Yashica AF and Minolta AF

Unread postby Dusty » Mon Feb 02, 2009 8:10 am

Granted, Roger, that auto focusing manual lenses is unique, but you're still stuck with the bad side-effects. I wish there was a way to just take my MD lenses and remove the MD mount and replace it with an Alpha mount. I could get some nice glass back, and wouldn't care that I had to manually focus.

Dusty
A couple of a350's, an a700 and now an a580, plus even more lenses.

rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Re: Yashica AF and Minolta AF

Unread postby rogprov » Mon Feb 02, 2009 8:16 am

Dusty wrote:Granted, Roger, that auto focusing manual lenses is unique, but you're still stuck with the bad side-effects. I wish there was a way to just take my MD lenses and remove the MD mount and replace it with an Alpha mount. I could get some nice glass back, and wouldn't care that I had to manually focus.

Dusty



There is :) ... have a look at this

http://www.pbase.com/pganzel/modification_of__58mm_f12_rokkor


Also have a peek at eBay item 150323882751
Roger

01af
Imperial Ambassador
Posts: 504
Joined: Sun May 20, 2007 2:44 pm
Location: Germany

Re: Yashica AF and Minolta AF

Unread postby 01af » Mon Feb 02, 2009 1:47 pm

rogprov wrote:
Dusty wrote:There's a similar converter available for the Minolta MC/MD lenses that will mount it on A-mount bodies.

Yes, there are plenty of adapters available to fit various lenses to the Minolta A mount ... but the uniqueness of this Yashica one is that it auto-focusses manual focus Zeiss lenses ... must be interesting at the very least.

That's not unique. The same auto-focusing 1.6× tele converter for manual-focus lenses also exists in a Minolta version. It auto-focuses Rokkor lenses on A-mount bodies, and also enables full-aperture metering with most MC and MD lenses. It's made by Sigma, and optical quality is pretty good---much unlike the dreadful 1.25× MD/AF adapters. Unfortunately (and notoriously Sigma) the auto-focus feature only works on the first-generation Minolta AF camera bodies, i. e. 5000, 7000, and 9000.

-- Olaf

User avatar
Dusty
Emperor of a Minor Galaxy
Posts: 2210
Joined: Thu Dec 18, 2008 5:04 pm
Location: St. Louis, Missouri, USA

Re: Yashica AF and Minolta AF

Unread postby Dusty » Mon Feb 02, 2009 6:35 pm

Forget the AF, just give me a good optical quality with a low multiplication factor adapter. Something like a 1.1x and 1/2 f stop loss. Of course, the time for this is long past. If was going to happen, it would have right after the switch to AF in the late 80s.

Dusty
A couple of a350's, an a700 and now an a580, plus even more lenses.

rogprov
Oligarch
Posts: 176
Joined: Sun May 20, 2007 5:10 am
Location: Gloucester, UK
Contact:

Re: Yashica AF and Minolta AF

Unread postby rogprov » Mon Feb 02, 2009 6:56 pm

01af wrote:That's not unique. The same auto-focusing 1.6× tele converter for manual-focus lenses also exists in a Minolta version. It auto-focuses Rokkor lenses on A-mount bodies, and also enables full-aperture metering with most MC and MD lenses. It's made by Sigma, and optical quality is pretty good---much unlike the dreadful 1.25× MD/AF adapters. Unfortunately (and notoriously Sigma) the auto-focus feature only works on the first-generation Minolta AF camera bodies, i. e. 5000, 7000, and 9000.

-- Olaf



I'd forgotten that one ... but as you say only works on pre-Dynax.

Not that want any of them ... jut interested in the history behind it all :D
Roger


Return to “Lens Lore”

Who is online

Users browsing this forum: No registered users and 1 guest

cron