35mm ZEiss is a MM lens or not?

[emmanuel_b1]

<p>Hi there,<br>

<br />I own a Contax AX with planar 1.7 50mm and Distagon 2.8 35mm.<br>

It seems program works only with MM lenses;this is the case normally:<a href="http://www.zeissimages.com/mtf.php">http://www.zeissimages.com/mtf.php</a> , but P mode doesn't work with the 35mm.<br />Notice that the smallest diaph is not written in green on the 35mm , but it is on the 50mm<br />Is there several Distagon 35mm at Zeiss?<br>

Thank you.</p>

[chuck_foreman1]

I suspect across the years they built slightly different versions. Clearly the MM lenses are marked! I remember that with the green aperture as a recognition for MM lenses, but aren't they also encoded with the letters "MM" on the lens somewhere too? What does the handbook say regarding lenses? I think the Program modes imply being able to "electronically" adjust the aperture (and the shutter) only the later MM lens have this possibility and if you examine your 50 and you compare these two lenses you can probably detect a slight physical difference with the aperture control and a slightly narrower bayonet mount. From the Pnet article I quote Tom Shea

 

[There are two types of Zeiss / Contax lenses - MM and AE. The MM lenses fully support all camera functions, including manual, program, aperture priority and shutter speed priority modes. The AE lenses lack the mechanism that allows the camera body to control the aperture diaphragm in the lens. Accordingly, AE lenses do not function in program or shutter priority modes. Zeiss has gradually been eliminating AE lenses. Only certain specialty lenses are available as AE. The great majority are now all MM lenses.]

"

[sumo_kun]

<p>Yes, the missing green means the 35mm you have is an AE lens so it won't work in P mode. Most lenses that are available in MM are also available in AE. The 15mm and 16mm are AE only, plus maybe some others.</p>

[fred_c1]

<p>If you have a Yashica 103, 107, 108 or 109 body, you can use P mode with AE lenses.</p>

[emmanuel_b1]

<p>I am in contact with a guy who uses AE lenses with P and Tv modes.<br>

He owns like me an AX body.<br>

The tip is to push and block the small index at 5 o'clock in front of the body.<br>

I tried without film inside and it seems to work.<br>

Picture shows a MM lens.<br>

AE lenses don't have the index to push the index body.<br>

<img src="http://membres.multimania.fr/ebgy/tempo/contax/contax_index.jpg" alt="" /></p>

[flatulent1]

<p>I read recently (like, this morning) that the difference between the older lenses and the newer MM lenses is a lighter aperture assembly in the newer lenses which is supposed to make it possible for the camera to quickly and accurately set the aperture blades while in P or Tv. When I find the source again I will come back and cite it here.</p>

<p>The two identifying marks designating an MM lens are the green minimum aperture number, and the presence of the little tab on the lens mount you see pictured above. I suppose they did this because they could not guarantee accurate exposure with the heavier apperture assembly. You know how fussy engineers can be.</p>

[flatulent1]

<p>Found it at the Contax history site. <a href="http://www.contaxcameras.co.uk/history.asp">http://www.contaxcameras.co.uk/history.asp</a><br>

The paragraph in question is near the bottom; search for 159MM, the camera that was introduced when the MM lenses were released.</p>

[k5083]

<p><em>I am in contact with a guy who uses AE lenses with P and Tv modes.</em><br /><em>He owns like me an AX body.</em><br /><em>The tip is to push and block the small index at 5 o'clock in front of the body.</em><br>

<em> </em><br>

That is correct. It works.</p>

<p><em>I read recently (like, this morning) that the difference between the older lenses and the newer MM lenses is a lighter aperture assembly in the newer lenses which is supposed to make it possible for the camera to quickly and accurately set the aperture blades while in P or Tv.</em></p>

<p>That is what Kyocera has told us ever since the MM lenses came out. However, I have been doing the trick Emmanuel describes for over 20 years, not just with Contax AE lenses but also with Yashica lenses and many third party lenses made for the C/Y mount, and never had an inaccurate exposure that seemed related to this issue. There may be a little truth to what Kyocera says, but not much, and my suggestion would be to go ahead.</p>

<p> </p>