Peter Smith wrote:
> Are you trying to make a pinhole Camera?
No, I'm trying to use one of those lensed peepholes that mount
into a hole you drill in your front door, that provides about
a 180-degree field of view. Reeeeealy cheap fisheye.
Additional info: Using a 55/1.8 instead of the 50/1.4, and
20mm extension instead of 12mm, things still aren't _sharp_,
but they're a tad sharper than with the 50. Enough so that
I can tell that I do have to change focus for different
distances as one normally does. I'll have to get a larger
lens cap to butcher, and some step-up rings, and try it
with the rest of my lenses to find which works best for this.
> If so you dont place the pinhole
> in front of the lens you REPLACE the lens completely - so it should be
> mounted in a (Black) body cap not a lens cap.
*nod* I've got one of those, too (screwmount, but I plan to make
a K one as well).
> The small hole will give a very wide angle and large DOF so focusing is not
> an issue. It is unlikely that there will be sufficient light transmission
> for your camera's meter to register so long exposure and experimentation are
> the trick here. Also the precision of the pinhole will greatly affect the
> sharpness of the image.
Field of view on a pinhole can be changed with extension tubes, BTW.
And you're right about precision of the hole -- I've not yet managed
to get one sharp enough in the thin sheets of brass I'm using (taped
across a larger hole in the plastic body cap). Last time I played
with it, I rubber-banded the screwmount body cap onto my Super Program
and set it on auto. Exposure was right, but I need a cleane hole.
-- Glenn
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