Pinholes from the Pinhole Factory
If you have not already done so, read the article Pinhole Cameras , and maybe some of the other articles such as:-
A pinhole is just that, a small hole in a light tight material that can be used to build pinhole cameras and similar items. Ideally pinholes are completely round, small and of a known size and in a very thin material or one that is constructed so that it has very thin walls at the edge of the pinhole. In all the other articles above we use cooking foil from the kitchen with a hole in it made by a small needle. This was supported on a card that was blanking out the rest of the light with only a small hole in it.
While this worked, it had the problem of holes differing in size and on occasions difficulty getting the material to always lay level.
As we wanted to experiment further, and have a better pinhole we bought a Pinhole Adaptor, that comes with a pinhole in place. There is another article looking at this and to allow us to make a better experimental kit we bought 4 pinholes, these you can see being used in the article Pinhole kit Mk3.
So the title is no joke, we did buy 4 pinholes from a commercial operation called the Pinhole Factory.
The Pinhole Factory, also known as Pinhole Solutions, have a variety of items for those with an interest in all types of pinhole photography and pinhole cameras, including a variety of film and paper cameras as kits that you can build yourself. They also supplied the Pinhole Adaptor, and can add a pinhole to a camera body cap that you send them. See Pinhole Cameras - Further Information for their web address, pricing etc.
The pinholes we purchased were 0.2mm and 0.3mm, 0.4mm and 0.5mm, giving me the full set to play with.
The 0.4mm pinhole and retaining ring - larger than actual size.
0.4mm pinhole greatly magnified, the square is 1cm in each direction
The pinhole is a 1cm piece of very thin steel double etched so as to have a small pinhole in the centre. Double etching means it has a saucer shape in each surface giving a small hole and thin walls, you also get a circular peel off pre-gummed circular tab with a hole in the middle that is used to hold your pinhole down, a piece of card that you can cut out to produce an exposure calculator, and a sheet of paper with some information. Amongst the information on the sheet is a table that indicates perhaps which pinhole you should be using.
The closest, even with the pinhole adaptor, is around 50mm, but using the tube set to make up my own arrangements I am working with a longer focal length than that.
Although in the earlier experiments I have used foil and this worked, we did not have a consistent sized hole or hole of a known size. Moving on to the next stage I wanted to look at how the size of the pinhole affects the image as well as experimenting more with different focal lengths and perspective correction.
By having all 4, that I can exchange, I can build an experimenter kit to allow greater understanding of pinhole photography, see this in the article Pinhole kit Mk3.
Exposure calculator larger than actual size,
actual size is about 10cm across.