Folks,
A couple of points:
the very wide angle shot: if you use a "flat" film plane you can get about a 3:1 ratio. ie if your focal distance is 50mm, the negative can be about 150mm wide before major light fall off. If your are using a curved film plane(as in the "pringlematic" photo--I'm guessing that was made using a Pringle's potato chip can) then you can go alot wider.
I use either brass shim stock or disposable pie pan aluminum for my pinholes. Both are
much easier to drill than beer(or soda)can aluminium.
I don't use sewing needles for drills because when I started to get interested in pinhole I didn't own a micrometer and couldn't tell what size hole I was getting. So I bought a set of very tiny drill bits. They are numbered 61-80 and they have served me well(the smallest is .0135" that is the #80).
There seems to be two major schools of thought about pinhole lenses: either "just poke a hole in something and shoot" or " I'm going to measure everything and get the optimum precision I can" An example of the former is a photographer I saw in Eric Rothery's book who built cardboard cameras with no pinhole in them until he shot them with a .22 caliber pistol. He used big camers/negatives so the almost 1/4 inch hole was was relatively "optimal". Slighly creepy self portraits I will search to see if I can find his pics online.
An example of the latter would be the Zone Zero series of cameras.
I fall some where in between those two examples as I will get a rough number thatgives me about f200 for whatever focal length I happen to be building and then use the closest drill I have- going smaller rather than larger if the calculated size is between two drill sizes.
I have not done much pinhole since this dern RF camera bug bit hard but I think I'm going to see how well I can combine the two.
An excellent pinhole site:
http://www.pinholeresource.com/index.html
Rob
EDIT: Eric
Renner NOT Rothery sorry