2 Mamiya TLR lens questions

[tom_alaerts1]

Hello,

 

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I have 2 questions about Mamiya TLR lenses

1. I just bought a Mamiya C33 with the chrome 105mm lens on it. Now I prefer a slightly wider angle as a standard lens, so a 80mm would be best. A dealer in the neighboorhoud will let me swap the lens for a black 80mm he has (I will have to add a little money for the service of course, he has to make a living too).

But I read somewhere that the mamiya 80mm is at best an average lens and that the 105mm is much, much better. Is any of this substantiated? For the best results, should I keep the 105mm and live with the more narrow angle?

2. This dealer has a very reasonably priced 180mm. The reason why it is cheaper than usual is that there is a very small dot on one of the inner lenses (difficult to see). He said if i notice it i can bring the lens back in. But has any of you experience with such a thing? Do you think it will produce a visible smudge or will it "only" affect edge sharpness at large apertures? Of course it is difficult to give an answer if you haven't tried the lens but perhaps someone was in more or less the same situation.

I prefer that eventual replys would also be sent to me personally.

Many thanks,

 

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Tom Alaerts

[joachim_hein]

Concerning the quality of the lenses, the chrome 105 is a 4 element

3 group construction, which is simpler than the 105 DS with 5 element 3 group. Usually the comments on the better quality of the 105 refer to the 105 DS. You might also want to check the entry of Tim Brown giving test results, in this digest. There is a real difference at aperture 5.6, but at 11 the 80 and 105 are almost equal. His results

refer to the 5 element construction.

 

Another important thing, chrome lenses are not servicable any more (no more spares available). For me this would be quite an important reason

for swaping too.

 

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Third thing, the 80 is 2/3 stops faster.

 

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Your other question is hard to answer. In general I would say it effects the optical quality similar to a piece of dust of same size.

The effect will be position dependent. Other things you should think

off: is it a chrome, a black one or a 180 super? You really want a

180? The 135 is half the weight.

 

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You might want to look at Graham Patterson's webpage:

"http://www.rdg.ac.uk/~slspatte/m_faq.htm" too.

He gives a nice overview on what is available.

[eugene_crumpler]

I'm probably late, but it turns out the I own a C33 and an 80mm black and 105mm chrome. I've test both and here is what I found:

The 105 chrome and 80 black are about the same. F11 is optimum for both lenses. The 105 is slightly sharper at f32 but not much. I did not test them wide open. The chrome lenses can not be repaired by Mamyia, but some interprising repair person can probably find some parts. I was fortunate(?) in that the 105 broke a few years ago and Mamyia fixed it while the parts were still available. So hopefully with the light use I give it, it will last!