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Thread: Update on ebay m4/3 to M adapter

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    Update on ebay m4/3 to M adapter

    I sent a question to Jinfinance regarding infinity focus and the adapter he sells and got this response:

    "thanks for the message... Yes, I do have similar reports, we checked, and some of the adapters are indeed off by 0.15mm ~ 0.2mm, we already making corrections in our new batch which should be due in about 10 days from now, so you can be assured that your purchase will be the right one...

    Sorry again for the troubles...

    best,

    R.J."

    I like someone willing to admit a problem and fix it. I ordered one and will report back when I get it.

    Tom

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    Senior Subscriber Member Steen's Avatar
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    Re: Update on ebay m4/3 to M adapter

    Hi Tom - welcome aboard.
    When did you get that response from Rong Jin ?

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    Re: Update on ebay m4/3 to M adapter

    After seeing Kachadurian's post, I messaged RJ via eBay about the problem I had had (you might recall from another post that I had to grind 0.10mm off the face of my adapter to make it focus to infinity.)

    It took about 1-1/2 days to hear back from him, but I got basically the same response. He said they are working to get a new batch of adapters with the correct dimensions into production, and offered me one at no charge when they are ready.

    I won't be able to say for sure until I have a replacement in hand, but it certainly sounds as if he is trying to stand behind his product, even if his OEM did let him down the first time.

    ...Which is great. On the other hand, I can't help noting that the adapter I ordered from CameraQuest, although considerably more expensive, was perfect right out of the box.

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    Re: Update on ebay m4/3 to M adapter

    Well errm ... Tom's post is from today ...
    I have just received my LM >> M4/3 adapter.
    My problem is that I was going to wait for the new Olympus and Panasonic M4/3 models before deciding which camera to get.
    But in that case I cannot test whether my adapter reaches infinity correctly.
    If only I knew that my adapter is actually from the new batch ?
    That's why I'm interested in knowing when your correspondences with Rong Jin took place.
    I bought my adapter the 4th of February.
    Last edited by Steen; 13th February 2009 at 12:18.

  5. #5
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    Re: Update on ebay m4/3 to M adapter

    Quote Originally Posted by bondo View Post
    That's why I'm interested in knowing when your correspondences with Rong Jin took place.
    I bought my adapter the 4th of February.
    The message he sent me made it sound as if they are still working on the revised adapter and that it has not yet been shipped. So I would say that if you already have received your adapter, chances are good that it is from the original, too-thick batch.

    (It's possible that some of the original batch are good and some are not; RJ described the problem as a "measurement error.")

    Do you happen to own a digital caliper, or know someone who has one? If so, you can measure your adapter and determine immediately whether it's okay or not. The ones that are "off" are off by 0.10 to 0.15mm -- this is a huge amount of error for a machined part, so it's easy to know you have a bad one.

    Incidentally, I recommend that everyone who is interested in messing around with adapters should own a caliper. They're useful and inexpensive; I got mine on sale at Harbor Freight Tool for around $10. I'm sure it isn't as precise or as durable as a more expensive model, but it's plenty good enough to separate the adapter sheep from the adapter goats.

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    Re: Update on ebay m4/3 to M adapter

    Quote Originally Posted by Ranger 9 View Post
    (...)
    Do you happen to own a digital caliper, or know someone who has one? If so, you can measure your adapter and determine immediately whether it's okay or not. The ones that are "off" are off by 0.10 to 0.15mm -- this is a huge amount of error for a machined part, so it's easy to know you have a bad one.
    0.10-0.15mm off from what? Do you have the exact correct thickness measure?

    regards, /Jonas

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    Re: Update on ebay m4/3 to M adapter

    Jinfinance gave me a refund - even prior to my returning it, so no complaints - my CQ adapter works perfectly.

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    Re: Update on ebay m4/3 to M adapter

    Quote Originally Posted by Jonas View Post
    0.10-0.15mm off from what? Do you have the exact correct thickness measure?

    regards, /Jonas
    My CQ adapter, which gives correct focus at infinity, measures 8.58-8.60mm thick as measured at several points around the circumference. This measurement is taken between the flats of the front and rear flanges.

    My RJ adapter, as received, did not allow lenses to focus to infinity, and measured 8.68-8.71mm at several points around the circumferences. So, I concluded that on average, it was about 0.10mm too thick.

    This is less than the deviation quoted in the messages several of us have received from RJ; apparently he is finding some that are too thick by a matter of 0.15mm to 0.20mm.

    Either way, this is a big enough difference that it should be easily detectable, even allowing for possible calibration differences among inexpensive calipers. If your adapter measures about 8.60mm between the flats, plus or minus a mm or two, it's probably from the "good" batch; if it measures about 8.70mm or more, it's probably from the "too thick" batch.

    Of course, the only real test is to mount a known-good lens on the camera using the adapter, and make sure it can bring a really distant object (1km or more) into focus when the lens is set to infinity. But if you don't yet own a Micro Four Thirds camera but already own an adapter, this type of measurement should be able to give you advance warning of potential problems.






    Incidentally, for real measurement nerds only: If you look carefully at the rear surface of either adapter, you'll notice it is "stepped" -- there is an outer ridge that does not contact the mounting flange on the G1 camera. Since this ridge adds to the thickness when measuring across the flats, a careful machinist might object that this makes my measurement inaccurate.

    Technically this is true -- but, as best I can measure (my depth gauge is too coarse for a really accurate measurement of such a small part) the "step" is only about 0.02mm high. This is relatively small compared to the deviation between the "good" and "too thick" adapters, so I think it can be ignored safely for this purpose. You'd need a micrometer rather than a caliper to measure the non-stepped area, and I don't have one of those (yet; maybe that's the next measurement toy I should add to my collection!)

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    Re: Update on ebay m4/3 to M adapter

    Thanks Ranger, I may try to find a micrometer or a digital caliper.

    I have now received a mail from Rong Jin saying that I can just try out the adapter when I actually buy my Micro 4/3 camera. No need to hurry, he promised to stay responsible for the correct infinity of the adapter by then. Nice fellow to deal with

    So now I am going to wait and see what Olympus brings to the table and also wait for the new version of the Panasonic M4/3 before I decide which camera body to go with. PMA is only a few weeks away so I guess we will see some more announcements by then.

    Btw. Rong Jin also asked me if I might be interested in other Micro 4/3 adapters and I told him about my preferences (provided the adapters will have more than just four Phillips Screws for the more heavy lenses).
    You might contact him as well and tell him which adapters you would like to see in production first.

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    Re: Update on ebay m4/3 to M adapter

    Quote Originally Posted by Ranger 9 View Post
    My CQ adapter, which gives correct focus at infinity, measures 8.58-8.60mm thick as measured at several points around the circumference. This measurement is taken between the flats of the front and rear flanges. (...)
    OK, thank you - then i know.

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