Printed Circuit Boards

New PCBs are in

New PCBs have arrived, these represent a significant upgrade to the previous alpha version. Circuit errors have been corrected and most importantly the light meter has been integrated into the board. Normally the components on these circuit boards would be placed by robots, as we are at the prototype stage still we are hand soldering all the components. This means working with tweezers under a magnifying glass and double checking everything before applying power to the circuit. It can be pretty easy to fry a board if you don’t do things in a methodical manner, so we are taking our time to get things right.

Once the key components are on board we can power up and run a few tests. Then the main chip, the “brain” of the TYCH can be programmed and full board functionality tested out. We’ve got 10 to build up into Beta units plus a few extras to allow us to continue development whilst people are testing the cameras for us.

 

3D printing prototypes

The rise of the machines

I have used 3D printers in my professional career for over 20 years now, the technology at the time was amazing and it has continued to develop at a phenomenal rate. The range of materials and printing processes available is simply mind boggling, you can print plastic parts, metal parts even carbon fibre reinforced parts. Traditionally the printers have been expensive to buy and difficult to get good results from without a bit of knowhow. This has led to a proliferation of bureau services which allow you to upload a model for quoting in different materials and then order for subsequent delivery. Unfortunately this slows down what could otherwise be a rapid design iteration tool, not much but enough to be frustrating.

One notable development in the past 5 years has been the availability of printers for home use. From early models with basic capability and poor reliability we are now at the point where you can purchase a reliable 3d printer for £100. I have watched with keen interest as a specific type of 3d printer, the resin printer, has gradually come down in price and now it seems is within the grasp of mere mortals. We took the plunge last month at alfiecameras and decided to invest in a shiny new resin printing machine, a Flashforge 8.9 to be precise, coupled with a Creality wash and curing station they can churn through a camera print in about 5 hours. Not just any old print either, we are talking high resolution dimensionally accurate parts which allow us to assess fit and function of design changes. I have been seriously impressed by what the machine can do.

The machines are currently helping me re-design the main housing of the camera to improve the light seals ahead of printing our beta testing units. We can even print the parts in clear so I can see what’s going on inside the camera and iron out any issues before we manufacture pre-production batches. If you have been on the fence about owning one of the cheaper machines I can recommend it, with a little bit of time invested in understanding how to get the best from the machine you can make a big saving on bureau services in both time and cost.

Disposable graveyard

Disposable? not any more.

When looking for lens options for the TYCH I found an old disposable film camera and this set a few wheels in motion. Whilst the high street labs send their disposable cameras off for recycling, the smaller labs are left with a challenge of what to do with loads of plastic and electronic waste. I got in touch with the wonderful people at Analogue Wonderland and in no time at all a large box of sad looking cameras was landing in my workshop.

There’s clearly some differences between cameras but most have a fairly standard meniscus polycarbonate lens. Thankfully the most common disposable has a reasonably high quality version with a nice helping of “character”.

The plan is to re-cycle the lenses in the 1st instance, but I do have plans for other parts of the cameras, just need to get the TYCH off the ground 1st.

USB Power

USB Power

One of the down sides of buying old second hand film cameras is some of them have strange battery sizes, it can be frustrating if you can’t track the right replacement down. Even when you do they can run out at the most awkward moments. We wanted to combine the benefits of new battery technology when designing the TYCH, we crammed in as much capacity as we could and combined with the low power requirements of the camera you can shoot reel upon reel of film without needing a re-charge.

When you do need to re-charge all you need is a USB C cable and a suitable charge socket, the TYCH will recharge in just a few hours if switched off. You can even use the TYCH tethered to USB power if you are planning on some crazy long exposures!

Light leaks

Light leaks and focus woes

It’s fair to say I wasn’t expecting the first few rolls of film to be perfect. I was very pleased to be getting recognisable images from the 1st working camera. Turns out there are a few issues to resolve. The focus is out of whack for all but the pinhole lens, pinholes have this lovely habit of always being in focus (albeit a slightly dreamy focus). For the meniscus polycarbonate lens things are clearly a little bit off. Images from my 1st 2 films taken with this lens have all been a little out of focus. I have a plan for fixing this issue, essentially it boils down to getting the lens positioned at exactly the right distance from the film. Solving that problem was going to need a special bit of kit, more on that later.

The other problem was a nice selection pf light leaks. My 1st black and white film was taken on an overcast day and I didn’t really notice anything unusual. Once I ran a colour film through the camera however the problem was a bit more obvious. If you are ever trying to track down light leaks there are a few things to bear in mind;

  • Red light leaks on colour negative typically come from the back of the camera as the light is filtered through the film base.
  • White light leaks are most likely from the lens side of the camera.
  • Any leaks that span the whole film from top to bottom are very likely due to rear door light leaks.

Turns out I had all of the above! Under strong sunlight the camera had more holes than a broken sieve.
The process for tracking them down involves close examination of your negatives, a good torch and some black tape. I am working on a redesign of the rear door labyrinth light seals (I had cut a few corners on the 1st design) which is now looking good. Also I spotted a rather large hole in the shutter mechanism which only shows up in strong light at certain angles! I’ve got a solution in the works for this as well so the next films should start to show the true potential of the TYCH.

Pinholes have arrived

Pinholes are in!

Turns out making pinholes is harder than it looks. You need a clean edge to avoid strange artefacts on your image whether it be flares or blurriness. A thin material is essential as you don’t want to create a light tunnel for reflections, not too thin mind as assembly becomes a challenge.
We looked at laser cutting, CNC machining and photo etching for our pinholes and in the end decided photo etching was the best option for the TYCH. This week we took delivery of our 1st batch, one a4 photo etched sheet of brass complete with nearly 300 pinhole plates on it! That should keep us going for a while.
If you are looking to make your own pinholes there are loads of resources available on the web with tips and tricks for making a one off pinhole. We make extensive use of Mr Pinhole for calculating pinhole sizes, focal lengths and f-stops.