It’s been a while but I’ve finally got around to developing the film I exposed with the Sardine tin pinhole camera. Check out the results! Of course they’re not the best images; there are flaws but with a little refinement I think it’s the start for something beautiful. I’m just relieved and stoked that it bloody worked! Even with very meticulous calculations there are a plethora of variables and thus still an element of the unknown.
So Bob just how did you do it? Well, I’m glad you asked. Although, I might be going over some of the things I mentioned in my last post about this camera I think it will further highlight the challenges and limitations of making a pinhole camera from a sardine tin.
In principal you just need a sardine tin, make it light tight, put some film in it and expose it – easy aye! Well almost. Like I mentioned in my previous post, the sardine tin is very shallow which, intrinsically creates a handicap. Because the film sits at the bottom of the tin and the aperture in the lid means that it has a very short focal length, i.e. the distance between the film and the aperture. If we consider that the average pinhole is between 0.5 – 1 mm in diameter then having a such a short focal length means that too much light gets through the pinhole risking over exposure.
For a while I couldn’t work out why the focal length affected how much light got to the film, surely that’s more to do with the aperture? This is true but as the aperture gets closer to the film it has to get smaller if you want to achieve an identical exposure. The way I think about this is to remember the aperture is the source of light. Now gather your mental imaging faculties and imagine that your walking along a dark road and there is a person say 300m away walking towards you with a torch. The torchlight appears as a dot or a very small source of light. As you get closer the torch light get bigger until the person is shinning the light right in your face and the source of light seem huge. The light isn’t any more powerful just bigger.
It’s the same with our pinhole cameras. As you move a 1mm aperture closure to the film it gets bigger in relation to the film.
So this means that for the camera to work I need a super smaller aperture or a shorter exposure [or both]. However, the smallest pin I could find was 0.2mm which was still to bit to big and thus would have required an exposure time of somewhere between 1/30 & 1/125, which is just too quick. Ideally you need an exposure time of around 1 – 2 seconds so you have a little room to manoeuvre.
So what do you do? I can’t reduce the aperture and limited to how short I can realistically and reliably reduce the exposure time. One other option was to reduce the ISO of the film I was using. If you’re unfamiliar, the ISO is how fast the film reacts to the light hitting it. So on a nice sunny day then ISO 200 will probably do you fine. If you’re shooting in low light you might want to use ISO 400, which is more sensitive, and will react twice a quick to the available light. Equally lowering the ISO means the films reacts slower to the light available. The slowest film I could find was Ilford PAN-F 50 [ISO 50]. Nevertheless this didn’t significantly reduce my exposure time.
So I was stuck. That was until I got a great tip off a local photography guru: Bob Clayton. Acupuncture needles!
So I contacted my local acupuncturist who was lovely and more then happy to oblige to my bizarre request. Turns out she drives past my house on the way to dropping her kids off at school so one morning she just pulled up and gave me a handful of needles. It felt a little dodgy but I got a collection needles with three different diameters: 0.2mm, 0.16mm and the smallest 0.12mm. [N.B. If you’re going to go this route PLEASE be careful and hygienic with the needles and dispose of them correctly]. The 0.16mm would have worked but using the 0.12mm together with the ISO 50 film gave me a ‘sunny day exposure’ time of 3.39 seconds. Spot on! So nothing left to do but to load the camera and get out and take some pictures.
My method was simply: Wait for a good sunny day and due to the 3 second exposure use a tripod. Also this freed both my hands to gently operate the shutter. I also took multiple photos of the same thing with different exposure times just in case.
There were a couple of operational issues with the camera. First I had to guess how much to turn the advance between each exposure and the film did tear which also made loading it into the developing tank a little tricky. Neither were the exposures amazing but I think using a light meter would of help judge / calculate a more accurate exposure time. So, there are a few issues with the design of the camera that I will address these for ‘sardine camera – mk ii’ but considering so many things could have gone wrong [even in the processing] I’m pretty happy.
This entry is just an update and will hopefully get mk ii operational soon and start to produce some better images. In the mean time if you have any questions or want to leave any comments I would love to hear from you [please keep it positive].
Please also check out Mr Pinhole’s website as he knows more about it then me and his site has been my reference book throughout this process.