No, of course I didn't look through an 250mm f/2.0 lens and point it
into the sun!
That would result in instant retinal meltdown - and anybody apart from
a complete
amateur doing this would arguably deserve it.
As I was sitting in the car waiting for the locksmith to fix the lock
on our back gate (I was locked out due to a broken key) I was pretty
bored... Nothing to photograph here that hadn't been done before...
All alone.
I decided to take the 250mm out of it's pretty metal case. I admire the
heft, the craftsmanship. I turn the focus ring. Ahhh.... smooth internal
focusing.
*bash bash bash* - the locksmith is trying his best to open the gate.
I take off the fine leather front cap (the back cap is still on). I
hold the lens in the sun. I admire the fine 9 curved diaphragm blades
that snap in place light as a feather.
The Cicadas are noisy in the trees outside. It's 35ºC or something
today.
Just as I start to think "Hmm, there's a bit of dust in this lens" -
and wondering
what extent of dirt inside a lens like this would ever make it worth
it to ship this
hunk-of-glass back across the atlantic to let John disassemble and
clean it -
and briefly recalling something John wrote about his reluctance to
disassemble this
particular lens - the corner of my eye catches the smoke erupting from
within my hands.
WTF!? The rear lens cap was being set on fire! I quickly twist the
rapidly melting
rear cap off the lens and threw it to the ground. In literally 20
seconds or so, this
lens focused the sun's rays to such intensity to melt through a
plastic rear cap.
For some reason, I immediately thought of the ramblings of Michio
Akiyama
on his Red Book Nikkor Aid website, where he drools over his
collection of
Ultra-Micro Nikkor lenses. I quote:
> "To put this lens, I obtained an old cloth. The pattern of old Japan
> is woven to this cloth.
> This cloth is a cultural asset preserved in the Shosoin.
> No one can buy the real thing in an old age.
> Because, the cloth was made in Japan of 1300 years ago. Then, I
> bought the cloth of the replica made for the tea ceremony in Japan.
> I put the graceful lens on the cloth of Shosoin.
> The Far Eastern light was seen."
I believe that, had one of Akiyama-san's precious Nikkor's spontaneously
combusted in his hands like my Zuiko 250/2.0 did today, he would have
had a
real religious experience worth writing about.
Addendum:
My lens is fine - only the rear cap suffered. There was a bit of
residue on the
rearmost lens element, but because this was, in fact, the drop-in UV
filter in the
rear, it was easily removed and cleaned.
This has me thinking though - if people burn holes in their Leica
cloth shutters so
easily with their teeny weeny ~39mm-diameter lenses, how quickly could
one do it with
this monster? Thank goodness there is a mirror in the optical pathway
in an OM body,
because what sort of damage could this inflict? Not that one would
ever - I hope - have
to point this lens into the sun like I have during actual photography,
but it dawned upon
me in a very real way how much light energy some lenses focus onto a
single point.
I wonder how long it would take to melt all the plastics (admittedly,
there are very few)
in an OM body if I were to set it up with this lens pointing into the
sun?
No, I wouldn't really do it (too afraid I could damage the lens) but
it's an interesting
though experiment.
20 seconds. That's all it took to make a rear lens cap smoke.
Sheesh.
--
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