If you do not find pinhole photographs aesthetically pleasing, then perhaps pinhold photography is not for you. The majority of pinhole shims are laser-drilled, but no harm in getting a dremmel out for a blitz. The inherent soft, out of focus look, with characteristically with excellent definition and contrast, is part of the pinhole magic; there are people out there who make pinhole cameras, then take the negs to a scanner, sharpen to the nth degree and give up because it does not look like a print from a camera. Derrrr. So, it's a pointless exercise to strive for a super-sharp pinhole. If it were possible, Leonardo Da Vinci would have come up with that first in the Tower of Winds. Nothing has changed over the ensuing centuries. The test pic of the lock and chain looks correct for a pinhole; never mind about the black line. Put the pinhole in a camera and shoot some real world subjects like buildings, landscapes etc, into the sun, sun off-centre etc to guage the effect of flare, which can quite often be sensational as an inclusion in pinhole images, dependent on the quality of the pinhole itself.
Lowes is more of a home improvement than hardware store. My local Ace Hardware has a variety of shim stock. So should auto parts stores.
Originally Posted by aterimagery
Like I say I'm not somehow against photos with less-than-perfect sharpness, but sometimes I may want a pinhole photo that's as sharp as possible and other times one that's fuzzier than it has to be. Recently I took the camera described in this thread and just drilled the hole out to 1mm without any deburring or anything just because I wanted a rather fuzzy photo and could use the extra speed in late daytime sunlight given that I was using 100 ISO film. (Arguably I should have just replaced the previous one with another one rather than destroy it but I'm intending to make a better pinhole and change the focal length after that anyway. And I was kind of in a hurry at the time.)
Jim: True enough. Until recently I've just wanted common stuff and Lowes has been a little more convenient to get to, but I'm going to go check out this locally owned independent hardware store and then probably the local Ace franchise. I need to get some varying grades of "jeweler's rouge" type compound for something else anyway.
Just to play with different ways of doing things, I ordered some inexpensive little tiny drill bits, the smallest of which is 0.33mm/0.013". I put the dremel in a drill press attachment, put the bit in the thing, and tried drilling some holes in some scraps of soda can aluminum just to see what would happen. Amazingly the bit didn't break and the holes it made looks pretty good (Aside from the burrs and thickness of course). Then I found out that my new dremel had started running at full 35,000RPM speed no matter what I set the speed control to so I'm having to send it back for a replacement. Anyway, due to the bit wobbling I'm betting that whatever holes it drilled aren't really 0.33mm but it worked better than I thought. I'll probably still just use a needle "lathed" against a grindstone to the proper diameter along with the dimple sand method, though I might see what i can do using some little tiny fine-grain grinding wheels or something.
Oh yea, did I mention that I like playing with tools, technical challenges, and inventing my own processes for things? Most of this tinkering has more to do with that than trying to get the ultimate tack-sharp images.
I still think brass shimming sheets are the best for your pinhole whatever anybody says about using aluminium sheets. Aluminium is too brittle to get a lovely clean cut hole.
I think the shims will also contribute to crisper images.
I use brass shim stock, the last round I managed to work with 0.001". I gather you're using the needle diameter as a size reference, but with dimple and sand, the diameter isn't that critical. The sharp point is used to create a bump, not size the hole. I usually lay the brass over a piece of smooth mat board as a work surface when I push the pin down to create a dimple. I then use wet-or-dry sand paper wet to work on the dimple. Using a sort of random circular motion I generally start with #400, then #600 as I get closer to final dimension. (I've not gotten obsessive enough to go above #600.) The pin/needle can be used to gently raise the edge of the hole a bit to sand more off if the hole is two small. The object is to wind up with a knife edge to the hole. I agree that brass works better than aluminum and two mil brass is easier to handle than 1 mil.
Hobby shops (especially the model RR oriented ones) often have a whole display rack of brass pieces used for model building, one of the standard items is a kit of brass shim, usually about 3x5 inches and in several thicknesses. Some auto parts places, and hardware stores carry shim stock also. At the model RR hobby shops you can find Blacken-It, a mysterious liquid that blackens brass nicely which is a good touch for a pinhole. Unfortunately the minimum size is about a 3 lifetime supply for pinhole work, and costs about $9 IIRC.
And yes, making the cameras is probably more interesting to me than using them! But I do go out every year for WPPD.