"whisky-dave" wrote in message
...
In fact I have 2 DoF marks on my film camera. But I bet you don't
know what they are for.

So do mine on my digital.


which one is that then. ?

you can't even work that out !

what does the sentance "So do mine on my digital"

Are you refering to the DoF marks tatooed on your penis.

your digital what.....

Since someone (I think it was you but I'm not certain of the quoting) said
"I have two DoF marks on my film camera" and someone else replied to that
with "So do mine on my digital" I presume the latter was referring to a
digital *camera* since a camera is what you referred to previously. Standard
rules of English that you don't always need to repeat the noun..

I presume both of you are slightly imprecise since the marks will be on the
lenses for the film or digital camera rather than on the camera bodies
themselves.

As to the two marks, my first thought is visible and infra-red, unless they
are for the two extremes of a zoom lens (narrower DoF for same aperture at
longer focal length). For visible/IR, I presume as well as two DoF marks
there are two focus marks and that the different pairs of DoF marks are
roughly equally spaced about the respective focus mark.

Have I understood your question correctly? Are the two sets of DoF marks
(and also the marks for the different focus points) in different colours?
That's usually the convention for visible/IR.