In my last post I spoke about how I was drawing up plans for a large format pinhole camera. I continued to research exactly what I wanted to do and decided on one slight change of plan - a small one, but one that would allow me to break the project into two parts.
One important goal behind my pinhole camera was that I should be able to change the film/paper without much hassle. The camera will be sizeable by the time I am finished and dropping it into a massive changing bag to change out the negatives wasn't a option in the field. I needed a film holder that I could build the camera around. Taking to the internet, my face soon drained of colour and my project was sitting in tatters. A film holder brand new was a pricey piece of kit and second hand wasn't looking much better. There was no way I could justify the cost of a film holder when I'm trying to build a cheap pinhole camera.
During my research I bookmarked a website called Feeling Negative. It's a great website with lots of information on film cameras, scanning and camera building. The camera building was still incomplete at the time of writing this but he covered one very important subject for me - how to build a film holder. The design was basic and rough around the edges but it worked which was the most important thing. I read through the build and began laying down plans for an improved design that would suit my build and be a little more refined.
When I was laying out the plans I knew that thick card was going to be what I would need for this part - it would be more forgiving with the detailed edges and by stacking it I would create a rigid structure. I started with a piece of card that was 12x9" which was one inch bigger in width and height (with additional inch in the height to grip so I could pull it out the camera).
The layers were simple in theory and developed the original idea into what resembles a bought film holder. The first layer created a tray for the 10x8" piece of paper or film to sit in with the next creating a lip to hold in place. I tapered the lip back at the bottom of the film holder to allow me to slide the film or paper in from here. This was instead of trying to create two light seals at the top of the film holder - one for film and one for the dark slide - and it also gave me more room in a changing bag as I wouldn't need to have the dark slide out completely, only an inch or two to reveal the tapered lip. After that I created another layer that would house the dark slide and topped this off to seal the unit. The final step at this stage was to flip it over and and repeat on the other side to create a double dark slide film holder.
Next up was to create a light seal at the dark slide entry point. The original plan used the fuzzy side of velcro which were attached in an overlapping formation which was good but I decided to do it slightly differently. Instead of velcro I was using actual light seals that would be stacked in opposite directions to create a two stage seal like a darkroom door - pulling out the dark slide would allow one light seal to close before it was removed.
Finally I wrapped the film holder with a final layer of card to create smooth edges for putting into the camera.
The film holder isn't perfect by any stretch but it works and works well. The dark slides are just cardboard at the moment but I plan to change these for a something in black. The light seals at the top are crude at the moment but, again, they work. These will be refined to my original vision too.
The flexibility of the card when building the film holder got me thinking about the rest of the camera and whether it needed to be made out of wood - as originally planned - or if I could use cardboard...certainly as a prototype. It would allow the finer details to be cut into the cardboard and it was economical - there is a lot of good quality cardboard that is recycled through my work that I could recycle in a slightly different way. A re-sketch of my plans and it was clear I could have this ready by Worldwide Pinhole Photography Day this year - three weeks away.
I'll update shortly.