[LargeFormat] RE: lens board

[Jim Brick]

At 08:53 PM 5/18/2002 -0700, Karl Wolz wrote:
>Jim,
>
>While you're correct about the 90 on a Linhof, a recessed board will have an
>effect on rise, fall, and other movements with any lens shorter than that
>90.  This is due to the near fully compressed bellows binding.
>
>I've never noticed a significant amount of sharpness fall-off near the edges
>with my 120 Angulon, BTW.  I used to own a 90, and had no problems with it,
>either, but that's been a long time ago and I don't have any evirence to
>support that statement.  My 120 Angulon is the one lens I would take on trip
>if I were limited to just one lens.
>
>Karl Wolz


Everything you say is correct. But a 90 on a Linhof with a flat board does 
not compress the bellows enough to prohibit rise/fall/shift.

A 120 Angulon has a larger coverage circle than the 90 and it will, 
therefore, require more shift before you get into the fall off area... 
close to the edge. At f/22 and smaller, I believe the sharpness falloff is 
mute. Diffraction takes over.

:)

Jim