Digitar Lenses for Landscape

[willconnor]

I'm looking into the possibility of using Digitar lenses with a P25, P45, or Aptus 75 back.  Or possible 6x7 film.

From what I understand, the Digitars are optimized for f8 to f11.  While I think in most cases that may provide enough depth of field for wide angles, I'm concerned that with longer lenses (120mm to 150mm), I may need to stop down to f22, even f32.

Does anyone have experience with the Digitars between f16 and f32?  How do they perform relative to f8 - f11?  Is a 120mm Digitar at f22 better or worse (in terms of sharpness and contrast) than a traditional Large Format lens at f22?

Also, how do the Digitars perform with film?

Thanks!

Will Connor

[Jack Flesher]

I have owned a digitar 80 and currently own a digitar 90.  Simply stated these lenses are incredibly sharp.  I have read that Schneider spec'd them at 170 lp/mm center resolution!  

It is my understanding that they are sharpest at f8 and f11 but I noticed no significant loss of resolution at f16.  I only used mine once or twice at f22 and would say it is at least as good as its 4x5 couterpart at that aperture.

My 90 has an image circle just over 100mm at infinity, so while it won't cover 4x5 it will cover say 6x7 with some room for movement.  It will also cover more at closer focus distances.

Hope this helps,