Do lens element serial #s have to match?

[mjs]

I have an old Schneider lens of about 12"; the serial numbers on the front element and on the rear element don't match (not even close.) The lens works ok (for its age,) but I'm curious about whether one would expect the serial numbers of front and rear elements to match or not? If not, is there a down side (other than resale value,) to them not matching?

Mike

 

[Dan Fromm]

Well, there's always the possibility that the front is for one focal length and the rear for another.

 

[Vaughn]

There is a chance that the shutter is not original (obviously not original with at least one of the halves), so the spacing may be less than optimal.

 

[Ole]

Let me guess - it's a 300mm Symmar?

Most lenses don't have serial numbers on both front and rear cells, but many convertibles do.

Since convertibles are made to be usable with only the rear cell (and sometimes with only the front cell too), spacing and matching of cells is less critical than with some other lenses.

So since both cells have serial numbers, chances are it's good enough.

 

[GeorgesGiralt]

I've just checked, none of the Schneider lenses I own have a serial number on the rear element.
Xenar f:4.5 f=150mm, Angulon F:6.8 90mm, Symmar 210 f:5.6, Xenotar f:2.8 100 mm. sorted by production dates, from the fifties to the seventies.