When I just pressed the 'send' key there is another thing come up in my
mind, I just assumed the whole lens group will move during focusing (the
most simple focusing), if the RF lens is with internal focus or focus with
just the front element group then focus error could happen with an adapter
of wrong thickness.
C.H.Ling
----- Original Message -----
From: "C.H.Ling"
>I also believe the adapter has nothing to do with the focus accuracy of the
> RF (also SLR). Consider if the adapter is 0.02mm thicker, the glasses with
> RF coupling mechanism will also move 0.02mm and you just need to focus
> closer so only the focusing scale is affected.
>
> C.H.Ling
>
> ----- Original Message -----
> From: "Jim Nichols"
>
>> Wayne,
>>
>> I am not trying to be argumentive here. I've used Leica rangefinders for
>> more than 50 years. True, the lens will focus, but the rangefinder does
>> not
>> know where it will focus unless the distance between the LENS FLANGE and
>> the CAM FOLLOWER is correct. An out of spec adapter will cause this
>> distance to be incorrect. The proper adapter thickness is 1.00mm.
>>
>> One can compensate for an incorrect adapter by adjusting the cam
>> follower,
>> but it will be correct only for that lens/adapter combination, and will
>> be
>> incorrect with other lenses.
>>
>> Jim Nichols
>> Tullahoma, TN USA
>> ----- Original Message -----
>> From: "Wayne Harridge" <Sent: Thursday, January 22, 2009 4:08 PM
>> Subject: Re: [OM] Photos from Bessa
>>
>>
>>>
>>>
>>>
>>>
>>>> Jim Nichols <> wrote:
>>>>
>>>> Wayne,
>>>>
>>>> The thickness of the adapter does affect the point of contact between
>>>> the
>>>> lens cam and the rangefinder cam follower. Therefore, if the adapter
>>>> is
>>>> not the correct thickness, the RF image will not come together at the
>>>> distance at which the lens is actually focused.
>>>>
>>>
>>> Think about it, maybe draw a diagram - the focussing scale will be out
>>> but
>>> the lens will still focus correctly !
>>>
>>> ...Wayne
>>>
>
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