My main digital camera is a Canon 1Ds mk2. It’s a full frame camera from 2004, I believe. I have grown fond of using vintage manual focus lenses on it. Mainly Nikon F mount lenses, but also a couple of M42 lenses. That is all fine and dandy with a cheap adapter from Amazon or Ebay. Or so I thought.
If you get an adapter without focus confirmation and have an older EOS body, you might run into a little problem. But before you get to modifying your adapter, test it. If it works, modification is a waste of precious shooting time.
On older EOS digital bodies – probably also on EOS film bodies, there is a little pin on the left side of the lens mount. When you mount a lens or an adapter, this pin is pushed up. For some reason though, it has to be able to move down when something without a focus chip is mounted. But the flange on the adapter prevents that. If you try to shoot your camera with an adapter mounted, the mirror will open and then lock up and you have to switch the camera off and on again for it to pop down.
To solve this, I actually filed off a piece of one of the flanges, as you can see on the pictures above. Now, which flange do you file? Answer: The one on the opposite side of the red EF-mount dot, as you see.
When you have finished filing your adapter, make absolutely sure there are no metal filings or metal residue of any kind left on it. If it gets in your camera, it can mess up quite a few things. If it is a digital camera, it can damage your sensor severely. I had a piece of metal get stuck by the lens contacts which caused my mirror to jam, just like what happens if you don’t file the adapter. This happened while I was using a fully automatic AF lens, so needless to day, I almost pooped myself, thinking my camera had broken. Lucky for me, when I popped off the lens, a piece of metal filing fell out and all was good again.
The Yashica Electro 35 GS is a rangefinder camera manufactured in Japan between 1970 and 1973. It features a 45 mm f/1.7 lens with aperture range up to f/16. The camera uses aperture priority auto exposure with shutter speeds ranging from 30 sec to 1/500 as well as a bulb and flash sync setting.
The Electro 35 GS was originally designed to be powered by a PX32 5.6V mercury battery, but because of environmental concerns, mercury batteries are no longer produced. In stead a few other options are available. I chose a 6V silver oxide battery, labelled 4SR44. There is also an alkaline version called 4LR44, but alkaline batteries loose voltage when used, which could result in incorrect metering. The battery itself is too small to fit in the camera’s battery compartment, however a quick fix solves that problem.
What you need is:
- A ruler
- A utility knife
- A pencil
- A piece of rubber tube or garden hose with a 16-17 mm outer diameter. I used a piece of soft 16/12 tube for aquarium pumps bought at the local pet store .
- Aluminum foil
Now, you need to create an adapter for your battery. The total length of battery plus adapter is going to be 4 cm. The 4SR44 battery itself measures 2.5 cm, so what is missing is 1.5 cm.
Cut a piece of tube 2 cm long. This allows for the battery to be inserted 0.5 cm into the tube. Make sure you don’t insert the battery too far into the tube. It fits very tightly and thus is very hard to pull out if inserted too far.
Take a piece of aluminum foil and curl it up to fit inside the tube. Put the tube on a hard surface, standing up and stomp the foil inside the tube with the back end of a pencil. Repeat this till you have a 1.5 cm long aluminum foil plug filling up one end of the tube and 0.5 cm of free space at the other end. Make sure the foil sticks out just a little bit, so it can connect to the electrode in the battery compartment – but not too far as it might short circuit everything by accident.
Now put the battery into the tube and insert it into your camera’s battery compartment. I prefer to put the + end inside the tube, but you can do it the other way around, if you’d like.
Use the camera’s built in battery checker to ensure everything is connected properly.
That is all. Enjoy shooting your awesome rangefinder camera!
PS: This should apply to all Electro 35 models as far as I know. Please correct me, if I am wrong.