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Old March 22nd, 2009, 09:09 AM   #1
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Problem with lens mount adapter (mamiya645/B4)

I have been testing a new lens adapter that allows me to use a Mamiya 645 lens on a B4 mount. It works great with lenses up to 200mm but the image is soft with my 300mm & 500mm. Both seem to work fine on a Mamiya stills camera. I am wondering if anyone has an idea of what might be going on? It is not a focus issue so much as a general softness across the whole picture. Thanks

David Wright
www.lunaseafilms.com
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Old March 22nd, 2009, 09:33 AM   #2
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You might consider posting what camera / adapter / Lens / you are using for a troubleshooting starting point.
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Old March 22nd, 2009, 10:06 AM   #3
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Equipment info

Camera - Panasonic HDX900
lens- Mamiya 645, 100mm & 210mm- work well
300mm & 500mm- soft images (not focus, just a general softness)
Adapter- Mechanical adapter allowing Mamiya 645 lens to be fitted on a B4 mount (no optics)
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Old March 22nd, 2009, 02:29 PM   #4
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If I remember correctly, an adapter like that without optics will give you a 6.8 X crop,
and is best suited for macro use. Which means not all lenses will focus to infinity, and some will be unusable.
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Old March 22nd, 2009, 04:11 PM   #5
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Infinity

I am actually on my third adapter and have had them made progressively thinner until I have one that does focus to infinity. My confusion lies around the fact that the longer lenses do not seem to work, focused on a subject that is close or far away.
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