Sorry, I think I've lost track of the purpose of these photos. I
thought that with the reworking of the adapter you were attempting to
see if you had infinity focus. Is that what these images are showing?
Chuck Norcutt
On 8/22/2011 8:12 PM, Jim Nichols wrote:
> Chuck,
>
> I started with a sheet of 80 grit laid flat on the top of my table saw, then
> finished up with 400 grit. The result is an adapter that is approximately
> 6.9mm in thickness. The only down side is that the lens screwed into the
> adapter approximately 45deg further than before, so the lens index, formerly
> at the top, is now down on the left side. No big deal.
>
> Here are some representative photos, with f stops. Just as a reminder, you
> can't use exact f stops in a title. I had to use dashes instead of periods.
>
> Although I shot at all marked stops, from 1.8 to 22, I only posted four
> images as examples. The sun was getting lower as the f stops got higher, so
> the light does change somewhat.
> http://gallery.leica-users.org/v/OldNick/Takumar+55+at+f1-8.jpg.html
>
> http://gallery.leica-users.org/v/OldNick/Takumar+55+at+f2-8.jpg.html
>
> http://gallery.leica-users.org/v/OldNick/Takumar+55+at+f5-6.jpg.html
>
> http://gallery.leica-users.org/v/OldNick/Takumar+55+at+f11.jpg.html
>
> Except for the softness of the lens at f/1.8, I think all of the images are
> acceptable. f/5.6 appears to be the best.
>
> Comments welcomed.
>
> Jim Nichols
> Tullahoma, TN USA
> ----- Original Message -----
> From: "Chuck Norcutt"<chucknorcutt@xxxxxxxxxxxxxxxx>
> To: "Olympus Camera Discussion"<olympus@xxxxxxxxxxxxxxxxx>
> Sent: Monday, August 22, 2011 6:26 PM
> Subject: Re: [OM] Was: mount mod; Now M42-to-4/3 Adapter Thickness
>
>
>> What's this? A metal turning lathe in the basement?
>>
>> Chuck Norcutt
>>
>>
>> On 8/22/2011 5:52 PM, Jim Nichols wrote:
>>> I just thinned my M42 down to 6.9mm, to agree with Chuck's specs. I will
>>> give it another try when I have time.
>>>
>>> Jim Nichols
>>> Tullahoma, TN USA
>>> ----- Original Message -----
>>> From: "Chris Trask"<christrask@xxxxxxxxxxxxx>
>>> To: "Olympus Camera Discussion"<olympus@xxxxxxxxxxxxxxxxx>
>>> Sent: Monday, August 22, 2011 4:01 PM
>>> Subject: Re: [OM] Was: mount mod; Now M42-to-4/3 Adapter Thickness
>>>
>>>
>>>>>
>>>>> I think my statement caused some confusion. It was poorly crafted, to
>>>>> say
>>>>> the least.
>>>>>
>>>>> The lens that I referred to is a Leica-R Summicron 50/2, and must use a
>>>>> Leica-R to 4/3 adapter, so it won't work with the M42 adapter. What I
>>>> found
>>>>> with this lens is that the most distant object I can find comes into
>>>>> focus
>>>>> before the focusing index reaches the infinity mark. I have to back
>>>>> off
>>>>> from the infinity stop to get it in focus. This is the lens I used to
>>>>> see
>>>>> what an "infinity" image would resolve with my camera.
>>>>>
>>>>> I compared the previous image, made with a Pentax Takumar 55/1.8 lens
>>>>> and
>>>> my
>>>>> M42 adapter, to the Summicron image, and, at a distance, I find little
>>>>> difference. As Chuck pointed out, it appears that the earlier image
>>>>> was
>>>>> made at a smaller aperture, because the foreground was sharper.
>>>>>
>>>>
>>>> Okay, now I better understand. To rephrase what I stated earlier,
>>>> I'll
>>>> have to keep in mind to open up the aperture fully so as to reduce the
>>>> depth
>>>> of field when doing the focusing test later. That adapter is on a slow
>>>> boat
>>>> from Calcutta, so it's going to take a couple of weeks before it
>>>> arrives.
>>>>
>>>> Chris
>>>>
>>>> --
>>>> _________________________________________________________________
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>>>>
>>>>
>>>
>>>
>> --
>> _________________________________________________________________
>> Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
>> Archives: http://lists.thomasclausen.net/mailman/private/olympus/
>> Themed Olympus Photo Exhibition: http://www.tope.nl/
>>
>>
>
>
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