03-06-2017, 05:30 AM
Update on the ill fated AF20 F2.8D lens:
The couplet has been soaking in acetone for a long while, then nitro-methane, then xylene, all to no avail.
This modern lens cement is resistant to all those solventst!
"Le chlorure de métylène" (I've already forgotten it's English name) seems to be my last hope, albeit small. The product is available in France in what they call "Drogeries" a sort of hardware store, the trouble is most of these stores have slowly but surely closed down and this product has fallen out of popularity. I've rung around but as yet have not been able to locate a source.
Having ascertained that the cement isn't and probably hasn't been Canadian Balsam for some years this puts these sort of repairs out of the reach of amateurs as well professionals (the latter being uneconomical).
I've decided not to take the heating route, as JoJu said, "if you can't dissolve the cement your unlikely to be able to clean the elements".
In all the years of looking on ebay and the like, I've yet to see a S/H version of this lens come up for spares, maybe this "rarity factor" will put my example in good stead for someone looking for one to exchange his front element or some other part.
BTW. Reading around the few specialist sites out there, indicates that fogging is often caused by contamination of the glue at the point of manufacture, taking years to appear. A lot of the older D series Nikor zooms have suffered from glue related delaminations, looking with LED torch shows this up very quickly.
Oh well, a pity!
The couplet has been soaking in acetone for a long while, then nitro-methane, then xylene, all to no avail.
This modern lens cement is resistant to all those solventst!
"Le chlorure de métylène" (I've already forgotten it's English name) seems to be my last hope, albeit small. The product is available in France in what they call "Drogeries" a sort of hardware store, the trouble is most of these stores have slowly but surely closed down and this product has fallen out of popularity. I've rung around but as yet have not been able to locate a source.
Having ascertained that the cement isn't and probably hasn't been Canadian Balsam for some years this puts these sort of repairs out of the reach of amateurs as well professionals (the latter being uneconomical).
I've decided not to take the heating route, as JoJu said, "if you can't dissolve the cement your unlikely to be able to clean the elements".
In all the years of looking on ebay and the like, I've yet to see a S/H version of this lens come up for spares, maybe this "rarity factor" will put my example in good stead for someone looking for one to exchange his front element or some other part.
BTW. Reading around the few specialist sites out there, indicates that fogging is often caused by contamination of the glue at the point of manufacture, taking years to appear. A lot of the older D series Nikor zooms have suffered from glue related delaminations, looking with LED torch shows this up very quickly.
Oh well, a pity!