Age Of a Lens

[lost]

This one really makes me smile people worrying about the age of a lens some people probably use their cameras 30-40 times a year so a three year old lens may have been used a 120 times for a hour tops this translates into 120hrs work. Now take a lens a year old used by a pro lets say it gets 4 days work a week used for 5 hours a day thats 20hrs x 52= 1040hrs a year if both lens are mint and you don't know how they have been used you look at the dates and buy the newer one and think you have a bargain maybe not as big a bargain as you think.
Just a thought for the day next time you buy a lens
Regards All
Richard

please note the maths are based on the time the lens is actually in use not sat in the camera bag

 

[Musicman]

Some of the older Canon FD and FL lenses from the 60s and 70s (and from other makers too, but these are the ones I know) have radioactive thorium in the formulation of their glass. They tend to be rather good lenses - thorium was replaced by fluorite in later designs.

Aside from the radioactivity issue, over time, they tend to go yellow. Kind of useful if you're shooting black and white film as it's a kind of built in yellow filter

 

[lost]

Some of the older Canon FD and FL lenses from the 60s and 70s (and from other makers too, but these are the ones I know) have radioactive thorium in the formulation of their glass. They tend to be rather good lenses - thorium was replaced by fluorite in later designs.

Aside from the radioactivity issue, over time, they tend to go yellow. Kind of useful if you're shooting black and white film as it's a kind of built in yellow filter

That is useful to know im going to dig out some of my FD equipment to have a play with some FP4
Regards
Richard