Lots of threads on separating and re-cementing objectives that reference Norland UV cement but so far I haven't found a reference to which Norland cement is best for our application.
My particular situation is with an old Jaegers 4" f9 achromat and it's finderscope, both objectives show significant cement decay. I'm working on the finderscope first, easier to deal with and sort of a 'practice' run before tackling the main objective.
I've separated the finderscope elements with acetone (took several days of immersion), bought a pair of cast iron V-blocks from Ebay, am ready to buy some Norland UV cement.
However Norland offers what looks to be six choices:
#60, 1.56 refractive index, "good" rating as to "glass bonding".
#61, 1.56, excellent
#63, 1.56, good
#65, 1.52, good
#81, 1.56, excellent
I've read a reference to the refractive index of the typical crown and flint glass elements being 1.56 and 1.51 respectively (or is it the other way around?) and the cement should match one of these...is that correct?
Anyone have an real-life practical experience with any of these specific formulations?
Curiously Norland UV cement does not seem to be available on Ebay so it looks like I'll have to order direct.
I understand there are other solutions to this, like oil and the like but I'm interested in the Norland UV cement solution as I have several old camera lenses that need the same service.