Considering the recent Why are my film photos coming out so dark, even in bright sunlight? where the problem might have been a degraded light sensor in a classic 35mm SLR or might have been the wrong type of battery.
Also considering that some light meters, e.g. the Gossens, originally took a mercury battery that might these days be replaced by something with the same size but a different voltage, hence messing up the calibration.
Can an old-style selenium-cell meter such as the Weston Master still be relied on, or do they degrade with age?
As such, would a selenium-cell meter be an advisable accessory for anybody with an interest in old cameras, particularly film, in order to calibrate the accuracy of the internal (usually TTL) metering?
Updated: I intend to put some resources into answering this question, specifically in terms of how well a vintage meter such as a Weston Master can be expected behave (and what can be done about it). I'll be back.