Lens Testing Question

Archived from groups: rec.photo.digital (More info?)

"Charles" <ckraft@SAMTRAP.west.net> wrote in message
news:7014j1lnso95ugpif9e7a7dd266ka0vk1c@4ax.com...
>I read lens tests, I see them tested at different aperatures, and
> for zooms, different focal lengths. I don't recall seeing a test
> mentioning distance to the target. Is that not a concern?
> Except for macro, that is.


Yes it may, but it may also not make much of a difference.
It depends on the particular design being tested.

Conventional lens (resolution) testing was conducted at 100x or 50x
the focal length, which seems a good compromise and allows to
standardize the set-up, although may be difficult to achieve indoors
for longer focal lengths. It obviously is most relevant to test the
lens at it's most used focus distance, although that may differ
between users.

Bart