schneider 210 depht of field question

[jose_angel]

Could someone explain to me why we can find diferent Depth-of-Field Tables (4x5, 5x7, 8x10) in the schneider' web page

(www.schneideroptics.com) for a 210mm. lens ?

I can't understand why the same focusing distance could give diferent dephts of field in the diferent formats of this tables. Ex.: 210mm. lens, f/4, we can read 128ft. to 447ft. in 4x5 and 94ft. to infinity in 8x10. Could it refers to a diferent 210', (like an apo-symmar in 5x7 and a super-symmar in 8x10)?

I'll be thankful for any help. Jose.

[james_chow4]

The 8x10 DOF is probably computed with a different CoC as less

enlargement is required for a given print size/viewing distance,so

I'd guess maybe 0.2mm or 0.3mm. 4x5 DOF tables seem to be computed

around 0.1 or 0.11mm (Schneider's website lists it). You really need

to determine your own CoC size according to your results on film

and how closely you expect to examine the enlargements, and compute

your own DOF tables for your lenses.

[jose_angel]

James, thank you for your dedication.

Then, I understand that I can use either of this three DOF tables

with anyone of the formats, depending of the desired results, isn't

it?

Another question: Could I see differences in sharpness between two

8x10 contact prints, one with a COC of 0.3mm. and another with a COC

of 0.1mm. (or less)? (Examining the prints on the hands, without

loupe) I'm thinking to homebuild a 8x10 P&S camera. Suggestions are

welcomed...