[LargeFormat] New Memeber introduction/Pinhole day comments
Jonathan King
largeformat@f32.net
Thu May 2 16:10:12 2002
On Thu, 2 May 2002 12:09:55 -0700, Achal Pashine wrote:
>Schuyler, I converted my 4X5 camera into pinhole. Basically, I
>bought some
>brass shim from OSH hardware store and used the sewing needle=
in
>combination
>with emery paper to create very fine and perfectly round=
pinholes. I
>measured the size by scanning the pinhole and determine the=
actual
>size by
>comparison to known scale. It was approximately, 0.3mm. It=
worked
>best for
>17-20mm focal length.
>In the meantime, I had correspondence with another pinholer,=
Chris
>Patton,
>also from Stanford University; he provided me with variously=
sized
>copper
>Gilder grids (used in electron microscopy and are very cheap,=
one
>can get
>100s for $10-20!). Gilder grids are very precise in diameter and=
can
>be
>stuck onto larger brass shim squares with 3-4mm hole. It=
produces
>incredible
>details.
Great idea! I found www.guildergrids.co.uk. I think I'm going=
to
try them. They seem to have distributors through Europe, North
America, & Japan.
Thanks Achal!
Another source of cheap pinhole material that I have used for=
35mm
and 4x5 pinholes is aluminum soda cans. Not as elegant as brass,=
but
effective. One can is plenty of raw material for several=
pinholes.
The paint on the outside and plastic layer on the inside need to=
be
removed (sandpaper), but a few minutes work with several grits of=
sandpaper (I used down to 1500 grit) & a needle or fine drill=
makes
a nice pinhole. I usually dimple the aluminum, then sand down=
the
bump to make a very thin opening, while the thickness of the rest=
of
the aluminum makes it easy to handle.
Last winter I lead a group of 10-11 year olds making 4x5 pinhole=
cameras using that technique. Theirs came out fine, I find that=
about half of the ones I make are good and round (checked on a
scanner)
My pinhole day activities consisted of turning a Speed Graphic=
into a
pinhole camera, so I don't have images to contribute there, but=
I'm
developing my first Speed Graphic pinhole negs tonight!