Canon PowerShot S2 IS announced

Joe Miller wrote:
In article ,
"David J Taylor"
[]
A 24mm - 288mm (the same 12X zoom ratio) would be great, wouldn't it?

Cheers,
David

The problem isn't necessarily the 12x zoom, it's the shortest focal
length.
[]
One of my colleagues designs state-of-the-art lenses for his research.
I'll run this by him for a more definitive answer.

Joe

Oh, I do appreciate the design difficulties - I was thinking how
operationally useful a 24 - 288mm lens would be! You need to aim for
f/2.8 or better to provide some depth-of-field limitation, and for reasons
of diffraction f/8 is like to be the smallest aperture you would want.
I'll be interested to hear what your colleague says.

Cheers,
David

"David J Taylor"
wrote
in message
. uk...
Joe Miller wrote:
In article ,
"David J Taylor"
[]
A 24mm - 288mm (the same 12X zoom ratio) would be great,
wouldn't it?

Cheers,
David

The problem isn't necessarily the 12x zoom, it's the shortest
focal
length.
[]
One of my colleagues designs state-of-the-art lenses for his
research.
I'll run this by him for a more definitive answer.

Joe

Oh, I do appreciate the design difficulties - I was thinking
how operationally useful a 24 - 288mm lens would be! You need
to aim for f/2.8 or better to provide some depth-of-field
limitation, and for reasons of diffraction f/8 is like to be
the smallest aperture you would want. I'll be interested to
hear what your colleague says.

I appreciate and I now have a better idea of the difficulties in
designing a wide angle zoom. Just to add a personal note, I'd
much rather have a 28mm (or better 24) equivalent than even a
200mm.


--
James V. Silverton
Potomac, Maryland, USA

James Silverton wrote:
[]
I appreciate and I now have a better idea of the difficulties in
designing a wide angle zoom. Just to add a personal note, I'd
much rather have a 28mm (or better 24) equivalent than even a
200mm.

I've ended up with 24 - 432mm :-)

but in two cameras :-(

David