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Bolex h16 focus issue_ diopter? lens?


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#1 Robert Costello

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Posted 29 January 2008 - 12:29 PM

the is my first question on this very helpful website.

I have a Bolex h16 rex with a Angenieux 17-68 lens
the bolex is bayonet mount , lens is attached with c mount adapter

i was setting the 13x diopter by focusing the lens on an object measured 10' away.
i set the diopter to what appeared sharpest, but this was not very crisp.

when i adjusted the lens focus ring closer to the 15' mark the object became much sharper.
the tape measure in front of me clearly indicated that i was 10' from the object.

trust the viewfinder (what my eye sees) ?

trust the lens? (measured out) ?

there was another thread about a similar issue but it delt with a more obsure lens.

any help on this issue would be great!
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#2 todd eacrett

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Posted 29 January 2008 - 03:23 PM

You adjust the diopter without a lens on the camera. Take the lens off, point the camera at a light source, and adjust the diopter until the grain of the ground glass looks sharp through the viewfinder. Lock the diopter with the outer ring, put the lens back on and see if it's any better.
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#3 Chris Keth

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Posted 29 January 2008 - 04:43 PM

You adjust the diopter without a lens on the camera. Take the lens off, point the camera at a light source, and adjust the diopter until the grain of the ground glass looks sharp through the viewfinder. Lock the diopter with the outer ring, put the lens back on and see if it's any better.


This is what you should be doing. It take the lens out of the equation. The lens could potentially be off in its distance markings. I also find the course bolex screens tough to eye focus with.
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