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cone-viewing glasses

updated tue 31 dec 96

 

Bob Howell on sat 14 dec 96

Clayarters,

I was reading the "Suggestions from Readers" in the April, 1993 issue of
"Ceramics Monthly" and came across a suggestion to use didymium glasses.
Does anyone have any experience with these? Are they safe to use when
peering into a cone 10 kiln? If they're good where can I get them.

Thanks for your help.

Bob
Bob Howell
723 Terra Ave.
Alexandria, LA 71303
bobhowell@linknet.net

Karen Gringhuis on mon 16 dec 96

Bob - I have a pr. of didymium glasses. Having already had one retinal
tear mended, I do not fir without them. any good optician should be
able to make a pr. for you. Mine are NON-prescription in a frame lg
enough to slip over my regular glasses & so others can also share
them. Remember they are GLASS, not less breakable plastic.

That said, when I researched this, I phoned someone at the Corning Glass
Works in corning NY & I think they also tld me that a standard
sunglasses lens in gray or green would also give protection to your
retinas. If this is true, you can save $$ since the DD glasses will
probably run you over $100. My risk is high so to me it's worth it.

My understanding is that you do NOT want what welders wear because
you can see enough hru it.

But by all means get something. Retinas can be burned by looking
into a red hot kiln from the light. In your shopping, remember
you're not looking for UV-B ray protection like most sun gllasses
or like the coating on regualr glasses. good luck Karen Gringhuis

Kenneth D Wetfall on mon 16 dec 96

Bob,
Regarding didymium lenses( a.k.a. 'fire glasses'): yes I use them always
during my firings. I went to my optometrist and ordered prescription
lenses ( since I wear corrective lenses) and I change into these glasses
when I get to red heat. My optometrist recommended this route rather
than 'clip ons' so that I would be more likely to wear them through the
duration of the firing rather than take off the 'clip ons' then forget to
put them back on. I, too, fire to cone 10. Didymium lenses block
infrared rays(which cause cataracts) but do not block ultraviolet rays (
like from the sun and electric welding). Even if you don't wear
corrective lenses, your optometrist probably can order them for you.
Another source is: Wale Apparatus Co.
400 Front St.
Hellertown, Pa 18055
215-838-7047 fax>215-838-7440

They should only cost about $25-$50 depending on how fashion conscious
you are.( prescription lenses are more, of course) Hope you chose to use
them! Good potting!- Kenneth

Ken Moore on sun 22 dec 96

Retinas can be burned by looking
>into a red hot kiln from the light. In your shopping, remember
>you're not looking for UV-B ray protection like most sun gllasses
>or like the coating on regualr glasses. good luck Karen Gringhuis
>
>
At the risk of stirring things up again, according to four ophthalmologists
that I have spoken to and everything I know from 11 years of working as an
ophthalmic technologist, there is no risk to your eyes from looking into a
kiln's peephole a dozen times several times a week over a life time.
Thermal burns of the cornea are possible, but the drying and pain would make
you pull away almost immediately.

My recommendation, look from a reasonable distance, wear filtering lenses to
see the cones better if you like, but save your money if you're worried
about UV/IR injury.

> Didymium lenses block
>infrared rays(which cause cataracts) but do not block ultraviolet rays

IR has never been suspected of causing cataracts. UV has been in the past,
but several studies have changed our thinking here. Right now, our best
evidence is that cataracts are a function of aging (crowding of the
continually replicating cells of the crystaline lens) which can be
accelerated by smoking.

Julie Moore
Dirty Bird Pottery
Manassas, VA
kenmoore@pop.erols.com

Paul Monaghan on sun 22 dec 96

Ken Moore wrote:
>
> ----------------------------Original message----------------------------
> Retinas can be burned by looking
> >into a red hot kiln from the light. In your shopping, remember
> >you're not looking for UV-B ray protection like most sun gllasses
> >or like the coating on regualr glasses. good luck Karen Gringhuis
> >
> >
> At the risk of stirring things up again, according to four ophthalmologists
> that I have spoken to and everything I know from 11 years of working as an
> ophthalmic technologist, there is no risk to your eyes from looking into a
> kiln's peephole a dozen times several times a week over a life time.
> Thermal burns of the cornea are possible, but the drying and pain would make
> you pull away almost immediately.
>
> My recommendation, look from a reasonable distance, wear filtering lenses to
> see the cones better if you like, but save your money if you're worried
> about UV/IR injury.
>
> > Didymium lenses block
> >infrared rays(which cause cataracts) but do not block ultraviolet rays
>
> IR has never been suspected of causing cataracts. UV has been in the past,
> but several studies have changed our thinking here. Right now, our best
> evidence is that cataracts are a function of aging (crowding of the
> continually replicating cells of the crystaline lens) which can be
> accelerated by smoking.
>
> Julie Moore
> Dirty Bird Pottery
> Manassas, VA
> kenmoore@pop.erols.com


Julie,

I totally agree. If anyone is interested I presented pages of optical
power calculations last year for normal kiln temperatures. It should
all be in the archives. Any neutral density filter for comfortable
viewing, even cheap sunglasses are just fine.

Paul Monaghan
--
Paul J. Monaghan email: paul@web2u.com

WEB2U Productions --- http://www.web2u.com

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Louise K. Condon on mon 23 dec 96

On Sun, 22 Dec 1996, Ken Moore wrote:

> ----------------------------Original message----------------------------
> Retinas can be burned by looking
> >into a red hot kiln from the light. In your shopping, remember
> >you're not looking for UV-B ray protection like most sun gllasses
> >or like the coating on regualr glasses. good luck Karen Gringhuis
> >
> >
> At the risk of stirring things up again, according to four ophthalmologists
> that I have spoken to and everything I know from 11 years of working as an
> ophthalmic technologist, there is no risk to your eyes from looking into a
> kiln's peephole a dozen times several times a week over a life time.
> Thermal burns of the cornea are possible, but the drying and pain would make
> you pull away almost immediately.
>
> My recommendation, look from a reasonable distance, wear filtering lenses to
> see the cones better if you like, but save your money if you're worried
> about UV/IR injury.
>
> > Didymium lenses block
> >infrared rays(which cause cataracts) but do not block ultraviolet rays
>
> IR has never been suspected of causing cataracts. UV has been in the past,
> but several studies have changed our thinking here. Right now, our best
> evidence is that cataracts are a function of aging (crowding of the
> continually replicating cells of the crystaline lens) which can be
> accelerated by smoking.
>
> Julie Moore
> Dirty Bird Pottery
> Manassas, VA
> kenmoore@pop.erols.com
Julie, What do you mean "filtering lenses? Are you refering to the
Didymium lenses? Your info is very reassuring.Thanks.Rikki=LCON@LOC.GOV>

Richard Gralnik on tue 24 dec 96

There was an extensive discussion on this topic about a year (?) ago,
with recommendations for #5 or #5 welding goggles and some pretty well
founded conclusions that the levels of IR and UV you're exposed to
peeping into the hole for a few moments is negligible. One solution
offered that I plan to try was from Karl Platt. He said to look at
your cones through a piece of cobalt blue glass. Apparently this makes
the cones easier to see.

Richard
sunny, about 65 degF with a slight breeze here in Los Angeles
Beats the hell out of snow

Ken Moore on thu 26 dec 96


>Julie, What do you mean "filtering lenses? Are you refering to the
>Didymium lenses? Your info is very reassuring.Thanks.Rikki=LCON@LOC.GOV>
>

There was some discussion (not sure if it was this time around, or last
time) of colored lenses to make the cones easier to see. This is the only
type that seem useful, or necessary to me.

Julie Moore
Dirty Bird Pottery
Manassas, VA
kenmoore@pop.erols.com

Kenneth D Westfall on fri 27 dec 96


On Sun, 22 Dec 1996 11:11:26 EST Ken Moore writes:
>----------------------------Original
>message----------------------------
> Retinas can be burned by looking
>>into a red hot kiln from the light. In your shopping, remember
>>you're not looking for UV-B ray protection like most sun glasses
>>or like the coating on regular glasses. good luck Karen Gringhuis
>>
>>
>At the risk of stirring things up again, according to four
>ophthalmologists
>that I have spoken to and everything I know from 11 years of working
>as an
>ophthalmic technologist, there is no risk to your eyes from looking
>into a
>kiln's peephole a dozen times several times a week over a life time.
>Thermal burns of the cornea are possible, but the drying and pain
>would make
>you pull away almost immediately.
>
>My recommendation, look from a reasonable distance, wear filtering
>lenses to
>see the cones better if you like, but save your money if you're
>worried
>about UV/IR injury.
>
>> Didymium lenses block
>>infrared rays(which cause cataracts) but do not block ultraviolet
>rays
>
>IR has never been suspected of causing cataracts. UV has been in the
>past,
>but several studies have changed our thinking here. Right now, our
>best
>evidence is that cataracts are a function of aging (crowding of the
>continually replicating cells of the crystaline lens) which can be
>accelerated by smoking.
>
>Julie Moore
>Dirty Bird Pottery
>Manassas, VA
>kenmoore@pop.erols.com
>
At risk of stirring even more poop my optometrist advised me of going
ahead with getting Didymium to protect my eye from getting cataracts
prematurely. I already have a family history of cataracts and that
exposures to IR light could accelerate there forming. I am no expert in
the mater but have burned my eye from UV light while welding . I didn't
feel anything an till the next day so why should you necessarily feel
pain from IR light. I mite add the optometrists is a personal friend so
finical gain was not a factor. I have not had a chance to see him
recently and I know thing do change so right now I feeling a little more
confused, but would choose to be safe then sorry.
Kenneth