Re: Feather tracks in lens coatings - any preventative?

On 27 Jun, 10:58, heini <buerg...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
wrote:
Hi hj,
sounds like a good idea at a first glance, BUT:
metal parts in a microwave will fire sparks and make huge damage!
Ever put a CD in a microwave?

just heating up in a oven to 80 °C would sound like be a much better
idea to me...
without destroying too much, I think

In conclusion, I think UV is the best thing to try. Wear eye and skin
protection!

yours, heini

Yes, but I think the heat might jeopardise lens cement. Also expansion
within a tight mount might produce problems
I suggested putting the lens in a sealed polythene food container in
order to prevent the arcing you mention.
Perhaps this would prevent the fireworks! Why not try it with a CD in
a container, instead of a lens, and see what happens.
Also, as you know, glass is generally a very efficient UV filter, and
you would probably need to use a UV-C source to sterilise a lens with
fungus. Ordinary glass transmits 250-100nm very poorly. Less of a
problem with quartz glass. Personally, I wouldn't go near one of these
sources without really meaningful UV protection........seriously
dangerous stuff. Also, fungi are rather resistant to ionising
radiation damage especially when dry and "resting" - probably the same
for UV.
Hell, chaps, let's do the experiment ! But only on a worthless
lens!!!!!!
hj
.

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