Hi all,
Took my Olympus OM 4ti out for exercise yesterday. Pulled it out of it's
case with minty Tokina ATx 80-200mm f2.8 zoom attached.
Since buying this lens I have really come to appreciate it and would be lost
without it.
Took a few shots, and realised that there seemed to be "ghosting" during
focussing.
Looked at the front of the lens to find a patch of what appeared to be fungus
about 35mm in diameter in the front element group.
The lens itself (bought from a listmember) about 2yrs ago is pristine! Last
time I used the lens about 5 months ago it was fine.
UK importer wants £25, $40, to look at the lens. If they can get spare parts
it will be £60/$90 labour PLUS parts and tax.
I decided "nothing ventured nothing gained" and so proceeded to start to
dismantle it! This was not as foolish as it sounds, the problem seemed "right
at the front end"
Tokina atx on e-bay seems to have exactly the same problem! 270516683772
Undo 3 tiny screws and front cell pops out. The front cell consists of a
cemented doublet and a second lens.
The cement of the doublet had softened and run, and the "fungus" was cement
which had trickled down the rear of the element leaving filament trails and had
pooled in the centre due to the lens being stored face down. This cleaned off
with no problem. However the doublet now shows signs of de-lamination with
silvery patches between the elements.
What to do next?
Hope new elements are available, and that distributor will supply me with one
to fit myself. New distributor, lens 15? years old?
Look out for lens in Olympus fitting on e-buy and hope it does not have
problems.
Look out for lens in other fitting and either swop front cell into my lens or
change my lens mount onto other lens. (if lens cell is good.)
Get doublet re-cemented...if I can find a firm to do this.
I cannot understand how the doublet has de-laminated. The lens was in perfect
condition when I bought it. I have always used a front filter and have NOT used
lens cleaner on it. Stored in spare bedroom, no real exremes of temperature.
Has anyone had similar experience?
Advice gratefully accepted.
Any info on lens parts numbers would be VERY useful.
Regards
John Duggan,
Wales, UK
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|