My first attempt at making a camera from a sardine tin worked as well as I could have hoped, but there was plenty of room for improvement.
Read more about my first attempt here
One of the shortcomings of the original design [mk1] was that I was only getting around 25 exposures from a 36 exposure film. This I believe, is to do with the width of the ‘exposure chamber’. [might have just made that name up?] By this I mean each section of film had to travel quite a distance between the [light tight] unexposed film roll and the [relatively light tight\] take-up spool. This could potentially leave the film open to light from subsequent exposures hitting the previous exposure before reaching the take-up spool. To remedy this I added a screen / flap between the ‘exposure chamber’ and the take up spool that will hopefully protect the exposed film and the take up spool from said light leaks. This also means I’ve had to move the aperture slightly off centre.
The biggest and most exciting modification I’ve made is to the take_up spool. However, I must now confess that although my principal intention was to build a camera from things easily found around the house I have started to stray from this with a few of my modifications. My first attempt of a functioning take-up spool broke half way through it’s maiden voyage and subsequently some of the film ripped. Also, the design of the take-up spool encouraged further light leaks that aren’t always desired.
The first advance in design was to replace the former sewing thread spool with a proper 35mm spool and make wooden holders for the spool to sit in.
Then I made a wooden peg [above] that slots inside the spool hub, allowing it to turn. Into one end of the peg I glued a piece of 5mm K&S brass tubing. This can be bought from most model shops where model train enthusiasts hang out. I found a brass radiator/ central heating key for the advance, as the beer top was a little clumsy which a piece of K&S brass tubing fit perfectly.
In order to then connect the radiator key to the 5mm tube in the wooden peg I soldered a smaller 4mm piece of K&S brass tubing. I used silver solder as that’s what I had but lead solder that plumbers use is easier to get hold of from DIY shops and is much cheaper. Silver solder is much stronger too. This modification should hopefully make the camera completely light tight.
Once it came to attaching the film to the take up spool I could have just taped it, like you do with the Holga. However, 35mm spools have a clever little hook thing on the inside of the spool hub which holds it in place. I thought I’d try to be clever and attempt to recreate this by punching a hole in the beginning of the roll…
…but soon realised that the hole is a little off centre. I punched more holes in the film but made a right pigs ear of the job so just tapped the factory cut attachment from the old roll to my film.
This time I’ve loaded the camera with 100 ISO film which will make the exposure time around 1.7 seconds.
All in all I’m pretty happy with the modifications and the advance spool works perfectly. All I need to do now is expose the film, so please check back soon for my results.