The Frankencamera Mark 2: The nuclear option, 15 December 2023
The Frankencamera Mark 2: The nuclear option, 15 December 2023.
In a previous post I covered my first impressions of a generic folding camera from the 1920s or 30s that I wanted to use with Instax Wide film. On the whole this was in decent condition, though the lens was described as being hazy and full of fungus. I covered how I cleaned the body, the bellows (which, thankfully, were still light tight) and the film holders. I also covered cleaning the lenses and putting them aside to dry off. And that's where my troubles began.
After a couple of days drying off, the camera was ready to be reassembled. This mainly meant fitting the ground glass back, putting the film holders back together and repeating the front and rear lenses. The rear lens was 'fine' (for a nearly 100-year-old piece of glass), and the front lens looked fine also. Put when I looked at them side by side it looked like the front lens was a little ... duller. Sure enough, when I held them up to the light the rear lens was clean but the front lens was flat. I held the front lens over the camera of my smartphone and you can clearly see the difference.
I had another go at cleaning the lenses, this time using hydrogen peroxide to kill any remaining fungus, and after drying took another look; there was no difference. Viewing the lens close up with light it looked as though the haze was inside the lens. The rear lens is a single element, but the front lens is a two-element lens and the haze seemed to be inside the rear element of this assembly. But how could I get at that?
Looking closely at the lens it looks like it is comprised of two lens assemblies screwed together, it really is a lovely piece of engineering. So, I thought, what if I could unscrew the two parts of the lens element, then I could gain access to the hazy part of the lens and clean it up?
Using two needle nosed pliers I gripped the two parts of the lens gently and holding them tightly twisted the screw. I felt something move and thought it might be the whole lens twisting. I paused, tightened my grip and heard a little squeak. The lens element was loosened and I found I could unscrew the rest by hand. As the two parts separated I was delighted.
I soaked the hazy element in hydrogen peroxide for a few minutes while I cleaned the front element with methanol and also cleaned the metal mount. I then cleaned and dried the rear element. Already it was apparent that the haze was gone and the lens was clear. I cleaned the lens and wiped the mount with methanol and dried the mount. I then left to two parts to dry in the morning sun for a while.
Once thoroughly dry I screwed the two parts back together and tightened the screw. Before remounting the front and rear lenses I did a final lens check with the smartphone. The difference was amazing, now the lens was completely clear. I replaced the front and rear elements and now the image looks clear and bright on the ground glass screen.