In article ,
Alan writes:

It may need a lens with a longer focal length (longer than 26mm) as the
camera/lens combination has a resolution lower than a pixel count
suggests.

At night power of the illumination at 25m would have to be adequate and
a ' ring of leds' would probably be insufficient.

I haven't tried at quite that distance, but at shorter distances,
number plates (and rear reflectors) appear extremely bright
because of the way they reflect light back to the source.
Actually, this can cause the auto-iris to close up such that
the number plates and reflectors are the only items clearly
visible in the field of view at night.

The alternative is to get some software such as is used in CSI where you
will be able to read a whole number plate from a single pixel in the
source video.

;-)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]