[LargeFormat] 12" Commercial Ektar - lens board extension
Clive Warren
largeformat@f32.net
Wed Dec 12 18:28:07 2001
Here's a chance for all you peops with the good mathematical brains
to help me out!
Have decided to put a 12" f6.3 Commercial Ektar on a 4x4 board for
use with my MPP 4x5 outfit in the absence of a reasonably priced f9
300mm lens.
The MPP bellows extend to nearly 12" - I am thinking about making or
having made an extension tube integral with the lens board to allow
closer focusing and to make sure that it does focus at infinity. If
the extension tube is parallel to the lens and is say, 2 or 3" even
5" how much danger is there of mechanical vignetting from the
parallel extension tube?
Cheers,
Clive