Quote Originally Posted by wombat2go View Post
I have to amend, a little, my reply #11 to Chan
The electrical circuit and meter are basically linear however I see that the meter scale is somewhat non-linear, probably to correct the transfer function of the CdS LDR to match EV.
The EV scale of this meter ranges from 2 (iso 100 f/5.6 and 8 second) to 18 (iso 100, f/5.6 and 1/8000)
As to whether, back in the day, they designed the scaling by trial and error , and whether the LDR CdS cells were specially made for exposure meters, I don't know.
I think you did a bang-up job on the project. Restoring any kind of exposure meter and achieving anywhere near original linearity is enough to make you pull your hair out. I've pulled it off a few times, but not without spending days at it. On many jobs you just have to pick on end of the dial or the other, or somewhere in between where your linearity situation "bunches up" on you and you just have to live with it. But when you think about it, I suppose a lot of them came out of the factory not accurate from the depths of a coal mine to the surface of the sun.