I kind of doubt that Tim. A quick Google search failed to show any evidence
of hydrofluoric acid production by fungi (or any other creature for that
matter). HFA is remarkably nasty material that can only be stored in wax or
teflon containers. Besides I don't think the fungi actually etch the glass
in lenses but do damage to lens coatings.
BTW, a small correction; your stomach produces hydrocloric acid not
sulfuric acid.
Charlie
On Thu, Nov 12, 2009 at 2:06 AM, Tim Hughes <timhughes@xxxxxxxx> wrote:
> Interesting that site says that the fungus produces hydroflouric acid to
> etch the lens.
>
> Does anybody know if that is true, or just an an urban camera myth.
>
> It seems hard to imagine a living fungus producing such a strong acid, but
> I have no knowledge. A few other sites also mention explicitly hydroflouric,
> not just "acid".
>
> The GI tract produces fairly stong sulphuric acid, although it also
> produces sacrificial mucous to protect the epithelial cells underneath, so I
> guess possible.
>
> Tim Hughes
>
>
> --- On Tue, 11/10/09, Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
>
> From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
> Subject: [OM] Separated Zuiko 250/2, was: Inside the Zuiko 300mm F4.5
> To: "Olympus Camera Discussion" <olympus@xxxxxxxxxxxxxxxxx>
> Date: Tuesday, November 10, 2009, 9:43 AM
>
> I posted a note to the Yahoo camera repair group on re-cementing
> elements and got this response
> -----------------------------------------------------------------
> Yes, go here:
>
> <http://www.focalpointlens.com/fp_services.html#lens_separation>
>
> If Zuiko used balsam, it should be repairable.
>
> If Zuiko used UV epoxy, well, it may be hard to separate the lens
> doublet. Maybe even impossible.
>
> Good luck
>
> Vick
>
> To: camera-fix@xxxxxxxxxxxxxxx
> From: chucknorcutt@xxxxxxxxxxxxxxxx
> Date: Tue, 10 Nov 2009 12:03:25 -0500
> Subject: [camera-fix] Source for cleaning and re-cementing separated
> elements?
> ------------------------------------------------------------------
>
> Chuck Norcutt
>
>
>
> Chuck Norcutt wrote:
> > But there are folks who specialize in cleaning and re-cementing
> > separated elements. Given the value of the 250/2 it may be worth
> > considering.
> >
> > Chuck Norcutt
> >
> >
> > John Hermanson wrote:
> >> Ouch. I'm happy to say that all the 300s I've come in contact with have
> >> not been glued. Perhaps the ones I say at Olympus trying the patience
> >> of the techs were an anomaly. Speaking of lens defects....that reminds
> >> me that about a month ago, a customer in Norway sent me his 250 f2 due
> >> to sticky focus ring and poor focus issues. I put the lens on my test
> >> OM-2 and tried to focus out the back window. Focusing wide open on a
> >> reasonably flat plane (a row of flat bushes) only a central circle was
> >> sharp. The worlds most expensive "lens baby" ? The only defect I can
> >> come up with is that it has a separated element which makes the lens
> >> "beyond repair" (no parts available, and the elements were super
> >> expensive when they were available).
> >>
> >>
> >> ___________________________________
> >> John Hermanson | CPS, Inc.
> >> 21 South Ln., Huntington NY 11743
> >> 631-424-2121 | www.zuiko.com
> >> Olympus OM Service since 1977
> >> Gallery: www.zuiko.com/album/index.html
> >>
> >>
> >> Chuck Norcutt wrote:
> >>> Oh, oh! I forgot that this is the lens apparently assembled with super
> >>> glue.
> >>>
> >>> Chuck Norcutt
> >>>
> >>>
> >>> John Hermanson wrote:
> >>>> 300 4.5 with oil on the blades. A fun job! :-)
> >>>> ___________________________________
> >>>> John Hermanson | CPS, Inc.
> >>>> 21 South Ln., Huntington NY 11743
> >>>> 631-424-2121 | www.zuiko.com
> >>>> Olympus OM Service since 1977
> >>>> Gallery: www.zuiko.com/album/index.html
> >>>>
> >>>>
> >>>> Carlos J. Santisteban wrote:
> >>>>> Hi all,
> >>>>>
> >>>>> An unusual view of my F.Zuiko 300mm F4.5: <
> >>>>> http://www.flickr.com/photos/zuiko21/4085731295/>
> >>>>>
> >>>>> Taken with my new Lumix GF-1 (plus 20mm F1.7) -- review coming soon!
> >>>>>
> >>>>> The previous picture in my gallery is the only other one taken with
> this
> >>>>> little camera, buy maybe not up to anyone's taste. Lots more (either
> film or
> >>>>> digital) will be uploaded shortly -- I hope!
> >>>>>
> >>>>> Cheers,
> --
> _________________________________________________________________
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> Archives: http://lists.thomasclausen.net/mailman/private/olympus/
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>
> --
> _________________________________________________________________
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>
>
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