[sdiy] Do LDRs and/or LEDs age?

[Buck Buchanan]

Hi all,

Looking at Paul's awesome Buchla pictures got me to wondering about the 
lifetime and ageing of LDR/diode control devices - Varactrols, CLM6000, 
home-brew, and otherwise.

I guess it's a two part question:

Does a Cds cell/LDR age?  IE, its resistivity per amount of light 
change?  If so, could I assume this happens over a very long period of 
time?  Or does it "wear" from use with maybe more light exposure wearing it 
more and/or faster?

Same goes for the LED portion.  They seem to age/wear when run with too 
much current.  But how about when run in their specified range?  H&H says 
"...they last forever", but in the context of a voltage controlled resistor 
device I would think any weakening of the LED would affect the overall 
device's performance.  I've looked at a few data sheets for the LEDs I use 
but haven't found any age/wear characteristics.

Thanks one and all for any input on this!

Buck