All kinds of specifics which they once had on public file have now been mothballed by Schneider, but might be still accessible with some serious digging. Back during the incident itself, I actually saw the bracket on serial numbers in question, because I was thinking of buying one of those lenses myself. But at a certain point, they abruptly cut the cord in terms of warranty replacements. Kinda like hit n' run driving. I'd was a victim of that with another photo gear manufacturer already, so turned my attention to Fuji LF lens options instead.
OK Drew, I did wonder if you were referring to Tinsley.
There are probably two processes here. the optical joining of lenses on their surfaces is usually referred to as cementing, but there may be an outside covering of sealant too, which can also be part of the blackening of edges for stray light reasons.
There are typically two problems with cementing lenses that can give rise to problems :
Glasses that are too different in expansion coefficient, that come apart in time, with temperature swings.
Glasses on a doublet where both of them do not transmit enough UV for a UV-curing cement, where the bond is not fully cured.
Yes, and the expansion/contraction differential between moulded acrylic aspheric elements and real glass is probably the reason the functional size of such "hybrid" lenses is rather limited.
But back to Schneider edge sealant. I never had any "Schneideritis" until I took a particular lens on a backacking trip one November into a lengthy deep Southwest canyon where the differential temperature between the sun overhead and bitter night cold could be nearly a 90 degree swing! Ridiculous diurnal stresses. I'd be there wearing an 85 lb backpack trying to get enough water to make it to the next spring, jumping on pool ice with that pack n' all in 90 degree heat, trying to crack its thickness! Meanwhile, there were still icicles hanging from seeps on shaded adjacent cliffs. Yet in direct sun, heat stroke was a distinct worry. Gosh- and way up high, Anasai cliff ruins. No wonder skeletons of those people were symptomized by severe arthritis at only 40 years of age - lugging everything from rocks and water pots to baskets of corn up those cliffs under such temp swing extremes.
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