Re: Acute angle projection (variable/stretched focal point?)

On May 15, 12:37 am, Dave Bell <db...@xxxxxxxxxxxxxxxxxxxx> wrote:
Bob Knowlden wrote:
The "Schiempflug principle" describes object and image planes that are
tilted so that the two planes are in (paraxial) focus everywhere. (The
two planes intersect at the principal plane.) The images still show
strong keystone distortion.

Quite true, but depending on the application, keystone distortion may be
not an issue. For example, a projected keyboard - the image could easily
be shaped to produce a correctprojection.

Dave

Thanks for the help!
sorry on the delay'ed response, just got back into town, and I need to
spend some time understanding the "Schiempflug principle" and the rest
of the suggestions listed. I don't get to work with optics very
often, so, while I'm enthusiastic about learning this stuff, it will
take a bit of time to catch up.
I did want to note that Dave is correct in that I've already adjusted
the source image to correct for the keystone effect. I just warped it
inverse to the projection and the result looks good proportionally,
just that it only has the one focal point.
Anyway, thanks for the help! I'd be glad to have any more suggestions
and/or feedback! Great stuff!
-kevin
.