Saturday, September 7, 2013

The Downside of Cheap Adapters

My Leica-R 28mm f2.8 Emarit seems to perform differently on different cameras; very good on the Canon crop bodies, but it's horrible on the NEX-6, with basically the same size sensor as the Canon. I noticed it but didn't give it much thought, since I hardly ever use this lens. It is the least used Leica lens I have.  The edges on this lens is just terrible on the NEX-6. Then I put it on my 5D Mark II, and I was surprised to find that the edges are way better on it than on the NEX-6.

It didn't take long to realize that it was fault of the adapters; most of my adapters are cheap ones, and I am using two adapters for all my Leica-R lenses on the NEX-6. The reason is that I am trying to reduce the number of adapters to buy for different systems. Since I already have the adapters for Canon for most mount, I just bought a NEX-EOS mount, and then mount the Leica-R and other lenses onto the NEX-EOS adapter. Most cheap adapters don't have the precision as the more expensive ones, but most of the time we don't notice too much of it.  When stacking two adapters, the tolerance quickly fades and the errors in machining adds up. Most obvious sign is one side of image is less sharp than the other side.

I guess I am going to have to buy dedicated adapters for the NEX.

Colours! - Canon 5D Mark II & Leica-R 28mm f2.8 Emarit @ f4.5.

Rain drops - Canon 5D Mark II & Leica-R 28mm f2.8 Elmarit @ f2.8.

7 comments:

  1. Hi Yu-Lin,

    any adapter is a crutch adding more or less error to the optical system. Two adapters=2 times as many chances for errors.

    I used cheap adapters and saw no issues. When I changed to NEX-7 I thought it will improve to use a Novoflex adapter. It turned out that it actually was not better at all even it is 10 times more expensive that the cheap one I had.

    I learned my lession...

    Cheers

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    1. MAWK: it's true that the cheap adapters have gotten to be very good indeed, considering how much less they cost compared to the more exotic ones.

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  2. Hi, its interesting that you say that. Personally even though I use "cheap" adapters I never stack them, so I still find that two cheapies is better than so,e real expensive (so called) precision adaptors.

    I would be interested to see how you came to the conclusions you have. For instance if some tilt of the focal plane was happening I would expect to see the same effect as I do with my tilt adaptor. That is one edge would focus closer, the other further away.

    I would be interested in resolving this as it might also be down to different sensors and glass coatings on the next vs the canon.

    My OM21mm performs very nicely on film but poorly on 5D.

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    1. Good point about whether it's the sensor or the adapters. I haven't tried a single adapter for Leica-R lenses on the NEX, since I am cheap and didn't buy a dedicated Leica adapter, but I tend to suspect it's not the sensor, as many other lenses work well on the NEX-6. Perhaps, it's time to buy a dedicated Leica-NEX adapter to verify this.

      Strange that the OM21 is not doing better on the 5D. The 5D has a very thin aliasing filter and it should be actually better. Perhaps the adapter/focusing? With live-view, it would be much easier to verify but unfortunately the 5D does not have live-view.

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  3. Also, there is a polish eBay seller who makes among the most precise mounts I have seen. Usually machined from a single billet.

    Not expensive either (well, depending on the mount)

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    1. Yup. I bought my FD-u43 adatper from him and it was well made and very precise. Infinity focus is spot on. Unfortunately it does not work with some FL mount lenses, and the adapter I have is not very refined, meaning not well polished/filed. Very rough on the edges.

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    2. Oh yeah, and it was $80 plus shipping!

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