This beautiful Canon TX was given to me by my dad. It served him reliably for years, but was gradually replaced as digital cameras and smartphones became ubiquitous. One day, it went away for good.
Then a few years ago, my dad pulled this camera out of hibernation. Having long replaced it, he thought it was time to let it go. But before he could, I stepped in and asked if I could keep it. I didn’t have any real plans for it at the time, but I could see its potential. Plus, I thought it might make a nice memento, since it tended to be taken out at holidays, birthdays, and gatherings between family and friends – all the happiest moments of my childhood. My dad said yes, and so it sat on an end table in my bedroom for a few more years.
I had had the thought to begin shooting analog since I started learning more about photography last year, and this camera was just sitting there in my apartment. But it badly needed cleaning, and the hot shoe was rattling loose. I looked into getting it cleaned and serviced professionally, but the prices I found were higher than what the camera was worth. The other option was to service it myself, which intimidated me for a long time. All it would take was one small mistake to render the entire thing useless (and irreparable). Ultimately, though, I realized such a mistake wouldn’t condemn it to any worse fate than it had already suffered, and I got to work.
I started by taking off the aluminum top cover. To do that, the film advance lever, rewind mechanism, and shutter speed dial all had to come out (along with a few screws). The advance lever tripped me up a bit at first. It's designed with what appears to be a decorative top plate, which threads into the shaft, but so far as I can tell doesn't preload anything but a few washers below it. A second, left-threaded nut actually fastens the lever to the drive shaft. Of course, using a left-threaded nut makes sense when considered carefully, as it has to react a left-handed torque on the lever in normal operation. But I’m not a smart person, and only realized this after applying copious amounts of WD-40, getting nowhere, and finally consulting a youtube video. For a final curveball, two set screws had to be removed from the functional nut before it and the advance lever can be fully removed.
The shutter speed dial was just fastened with a spanner screw, and the rewind mechanism was threaded directly to the fork below - which I immobilized with a screwdriver in order to remove it.
Once the cover was off, the first thing I decided to fix was the hot shoe. Its construction was…non-intuitive. The hot shoe was fastened to the top cover via four screws, two of which threaded into a nut plate beneath the top cover, and two of which threaded into the shoe, with their heads interfacing on the nut plate. Why Canon chose this arrangement is beyond me, but it made it impossible to fully remove the shoe. Upon closer inspection, the threads in the plastic of the hot shoe were gone. One of the screws had sheared, and another had fallen out completely. Reusing the existing screws (or any screws) was out of the question, so I decided to use epoxy instead.
While the top cover was off (and after the epoxy had cured), I cleaned it thoroughly with Windex. It was challenging to clean, since it had lots of nooks and crannies – the internal corners were actually recessed, so they were difficult to get to. I made use of cotton swabs and toothpicks for this, and I think the attention to detail paid off.
Next up was cleaning the prism and focusing screen. The prism was held in place by a band of what appeared to be sheet steel, with some sort of foam used to preload the prism against the frame below. The foam had badly deteriorated, and was likely the reason the prism and focusing screen were so dirty in the first place. A sheet of plastic surrounded the prism in order to (I think) protect it from scratching from any of the surrounding parts. Some of the foam had stuck onto the plastic. Before I could clean the prism, both this and the strap would need cleaning.
The plastic cover was a simple matter of wiping down with IPA. For the strap, I removed as much of the foam as I could with a sharp knife before taking it for a swim in some IPA. Once it came out, I used some steel wool to remove the remainder of the foam.
I was a bit surprised to find that the strap was not steel, as I had expected, but brass. The silvery side must have been nickel-plated. I’m not sure why they chose brass, but…I digress. I chose light seal foam to replace the old stuff, since I would need it for the film door anyway (more on that later).
Cleaning the prism itself was rather easy, and just took some lens tissue, cleaning fluid, and patience.
I ran into one hiccup while cleaning the focusing screen - I apparently bent the aperture indicator slightly. I noticed this because on the first few tests, the ring and needle would get stuck together, preventing the needle from moving in changing conditions. This was easy to fix, though – I just took it back apart and bent the ring a bit with a sharp pair of tweezers.
The ring and needle can be seen in the upper-right hand corner of the focusing screen from this angle. The photodiode sits in front of and above the viewing window.
A brief aside on the functionality of the light meter on the Canon TX. The light meter consists of a needle and a ring: the needle to indicate the amount of light entering the camera, balanced for shutter and film speed, and the ring to indicate the size of the aperture. The exposure is “correct” when these two overlap. This is called match-needle metering, and it served as a bridge between external lightmeters and full automatic exposure.
The light meter receives both shutter speed and film sensitivity as input from the shutter speed dial, as well as a signal from a photodiode that sits above and in front of the viewing window, and responds accordingly. In order to clean the viewing window, I'd need to remove the rack-and-pinion that connected the shutter speed dial to the light meter. For the light meter to receive the correct input from shutter speed dial, the timing of this rack-and-pinion mechanism has to be correct. I should have made a mark to indicate the correct timing, because I unfortunately disturbed it on removal. It wasn’t too hard to figure out how to get it back together, though. But it did provoke some slight uneasiness until my first photos were returned.
Now everything was clean and I could put the cover back on. Before I did, I used a dab of solder to reconnect the hot shoe wire (which I snipped earlier to bond it in place).
With the covers back on, one job still remained: the light-seal foam at the film door hinge had deteriorated just as it had on the prism strap. I replaced this in much the same way, though I had to swab on the IPA this time.
Finally, since the kit lens my dad had used was in poor condition, I replaced it with a 50mm f/1.4 from Amazon. The lens came in terrific shape, and is now both the cheapest and fastest in my collection.
I took the camera to my college reunion to shoot my first two rolls of film. Each of these images was made on HP5+ pushed to 1600.
