RE: PPG Starphire Glass ( ?? Questioning My Data)

Eric,

This continued bickering over what might be true
in theory is nothing but a waste of our time,
especially since the issue can be much more
quickly resolved by empirical testing. I have
made it clear that if anyone does not agree with
the results of my tests they should test
themselves.

As for your suggestion that I had already made
up my mind before the testing began, I find your
comment arrogant and insulting. In fact, I made
it clear in a previous message that I expected to
see some increase in printing speed with the
Starphire glass and was surprised when I did not.
I suggest you learn to read a little closer
before misrepresenting my state of mind.

Your comment that my conclusion seems to be that
your data and methods MUST be suspect is utter
nonsense. In fact, the opposite appears to be
true in that you are the one who appears to find
suspect any data and conclusions that don't agree
with your own. I saw the same attitude from you
several years ago when our findings in comparing
printing speed of SA and BL tubes did not agree.
Your imperious questioning and tone made it very
clear that you did not believe my results because
YOU had found otherwise.

And let us not forget that this particular
exchange began as a result of your gross
misrepresentations of what I wrote in the
appendix on UV light sources in Dick Arentz'
book, not with me challenging any of your
findings, and it has continued with other
offensive statements from you. If ever there was
a clear case of the pan calling the skillet
black, you present it here.

Sandy

>Did you see the data I sent to you directly? There would be no gain by
>someone using a light source that outputs most of its energy above 360. The
>biggest advantage would be for users of BL bulbs, making PT prints with PD
>not just PD only. Over the life of the glass, which could be many years, the
>cost is very small per print. That is not the issue. I find quite hard to
>believe that you continue to dismiss the data as flawed without looking into
>the problems with the conflicting information. Your conclusion seems to be
>that my data and methods MUST be suspect.
>
>Why do I need to verify the data from PPG? I don't have the resources to do
>that. Have you called PGO to verify their web info? Come on Sandy. That is
>just good research. I have noi problem understanding the data. It is after
>all as clear as Starphire glass. You have known of the data that I posted
>back to at least 2000. Why didn't you ask PPG for such data? I am sure they
>would have provided it to you. You seem to have already made up your mind
>that there would be NO benefit from Starphire before the testing began. That
>is bad science.
>
>I have also emailed PGO to ask them to confirm their data on the web site.
>Get off your high horse.
>
>
>
>Eric Neilsen Photography
>4101 Commerce Street, Suite 9
>Dallas, TX 75226
>214-827-8301
>http://ericneilsenphotography.com
>
>> -----Original Message-----
>> From: Sandy King [mailto:sanking@clemson.edu]
>> Sent: Friday, November 18, 2005 9:18 AM
>> To: alt-photo-process-l@sask.usask.ca
>> Subject: RE: PPG Starphire Glass ( ?? Questioning My Data)
>>
>> Eric,
>>
>> Unless you have actually measured the
>> transmission of a piece of Starphire glass at 5.6
>> mm thickness there is no way you can be sure what
>> data is correct, that of PPG or PG&O. My
>> inclination is to suspect that they are both
>> right and that the problem is that the data is
>> being provided in a form that one of us does not
>> understand.
>>
>> Both samples I have come from PPG, one sample was
>> acquired back in 2000 or so, another a couple of
>> years back. Neither has any yellowish color to it.
>>
>> Barring further information this is where matters stand for me
>> at this time.
>>
>> 1. There is some conflicting data on UV
>> transmission of Staphire glass from what would
>> appear to be reliable sources.
>>
>> 2. Even if Eric's original data is correct and
>> the Starphire class does in fact transmit a high
> > percentage of UV radiation below 350 nm, none of
>> the commonly used light sources are able to make
>> much use of the increased transmission. For
>> example, especially SA tubes and the NuArc 26-1k
>> mercury vapor and metal halide bulbs, which put
>> out very little or no radiation in the range
>> below 350 nm. In theory the BL and BLB, which put
>> out some radiation down to 300 nnm, might be able
>> to take some advantage of a glass with increased
>> transmission in the 300 nm to 350 nm range, but
>> as noted, I did not observe this in my tests.
>>
>> 3. Get beyond the theory and test yourself. I
>> have tested samples of clear Starphire against
>> plain white float glass with carbon, kallitype
>> and palladium printing. I found no measurable
>> difference in printing speed at the thickness
> > tested, i.e. 3.3 mm. Printing was done with a
>> bank of BL tubes and with a NuArc 26-1k with a
>> metal halide bulb. I do not rule out the
>> possibility that the use of thicker class might
>> give different results. In fact, I was surprised
>> by the results with the thinner glass since even
>> the PG&O data indicates that Starphire transmits
>> a slightly higher percentage of radiation than
>> plain float glass in the range between 350 nm to
>> 450 nm, and I expected at least a slight increase
>> in printing speed. But I repeated the test
>> several times with the same result. No measurable
>> difference in printing speed between Starphire
>> and plain float glass at similar thickness.
>>
>> If you dispute my results, do your own tests and
>> share the results. And be sure to write up
>> exactly what you did so any of us can do a
>> verification check on your results. In fact, I
>> encourage anyone on the list who believes there
>> is anything to be gained by switching glasses to
>> make the comparison. But until see the results
>> of empirical testing that proves Starphire offers
>> significant practical advantage over plain white
>> float glass I will personally hold on to my money.
>>
>> Sandy
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> >I sent Sandy a tif of the particular data. Not sure what more
>> I can do for
>> >you Sandy. The Information on the PGO site is accurate except
>> the
>> >transmission portion. It does however, seem to match
>> SOLARPHIRE composition
>> >and the transmission data. Solarphire has a transmission of
>> about 5% at 320,
>> >33.9 at 350nm. Perhaps the people at PGO have their web site
>> information
>> >wrong. Where did you get your sample? PGO? Or directly from
>> PPG?
>> >
>> >Eric Neilsen Photography
>> >4101 Commerce Street
>> >Suite 9
>> >Dallas, TX 75226
>> >http://e.neilsen.home.att.net
>> >http://ericneilsenphotography.com
>> >
>> >
>> >> -----Original Message-----
>> >> From: Sandy King [mailto:sanking@clemson.edu]
>> >> Sent: Thursday, November 17, 2005 11:28 PM
>> >> To: alt-photo-process-l@sask.usask.ca
>> >> Subject: Re: PPG Starphire Glass ( ?? Questioning My Data)
>> >>
>> >> Since I have not seen the data that was faxed to
>> >> Eric today by PPG I have no idea how it compares
>> >> to the data he provided back in 1999. However,
>> >> there is still a real discrepancy here with the
>> >> data. Last evening I sent to the list a link to a
>> >> data sheet from Precision Glass and Optics,
>> >> www.pgo.com. The specific link was
>> >> http://www.pgo.com/pdf/ppg_starphire.pdf.
>> >>
>> >> Now, here is the thing. PG&O is one of the actual
>> > > fabricators of PPG Starfire glass. If you go to
>> >> the link above you will see that the information
>> >> they provide about this glass is very specific in
>> >> that it includes things such as available
>> >> thicknesses, chemical composition, electrical and
>> >> thermal characteristics, as well as transmission
>> >> from 330 nm up to 2100 nm. You really get the
>> >> impression that the folks who prepared this data
>> >> sheet knew their stuff. And I would think that if
>> >> anyone would know the real transmission data it
>> >> would be a fabricator rather than distributor.
>> >>
>> >> Now, the plain fact is that the transmission data
>> >> provided by this fabricator of Starphire, at 5.6
>> >> mm thickness, is very different from what Eric
> > >> provided back in 1999, and I presume very
>> >> different from the data he was faxed today by
>> >> PPG, since he claims it is very close to his old
>> >> data.
>> >>
>> >> So Eric's information is interesting, but it
>> >> hardly closes the case on the question of the
>> >> real UV transmission of Starphire. Course,
>> >> analysis by spectrophotometer would answer the
>> >> question and I hope to find someone to do this
>> >> testing.
>> >>
>> >> BTW, if anyone would like to test the Starphire
>> >> glass against plain white float glass, which I
>> >> encourage, you can obtain a sample piece of
>> >> current production Starphire in 4" X 6" size by
>> >> calling the folks at PPG. I have also heard that
>> >> some Lowes stores stock Starphire, but have never
> > >> seen it in my area of the country. Just make sure
>> >> that the float glass to which you compare it is
>> >> of modern fabrication and has no coating.
>> >>
>> >>
>> >>
>> >> Sandy
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> >After last nights back and forth, I was indeed going to
>> call PPG.
>> >> >
>> >> >This required all of 3 minutes and a short wait for a
>> return call. I
>> >> >received a call back from Penny Bridges. She has since
>> faxed to me data
>> >> for
>> >> >both the Starphire glass and SOLARPHIRE glass. The
>> thinnest that the
>> >> >Starphire is listed as being manufactured is 1/8” or 3.3mm
>> and all the
>> >> way
>> >> >up to ¾. The data sheets do differ somewhat from those I
>> received in
>> >> 1992
>> >> >as one would expect; most businesses update their
>> literature. I received
>> >> >separate sheets for 4mm and 8mm and this one combines the
>> information and
>> >> >transmission data in 10nm increments and only shows
>> transmission data for
>> >> a
>> >> >glass with a thickness of 5.66mm. It does not show up on
>> the available
>> >> sizes
>> >> >but that is what is referred to in the chart.
>> >> >
>> >> >While it does not match my data, as one would expect from
>> different
>> >> >thickness of glass, it does come darn close to the 4mm
>> data that I have.
>> >> It
>> >> >is not what I believe to be true as Sandy indicated in his
>> email, but
>> >> what I
>> >> >know to be true based on the manufactures data. Penny said
>> that they have
>> >> >not changed it since they first starting making it but do
>> offer a
>> >> coating.
>> >> >
>> >> >It took very me little effort and would certainly have
>> been something
>> >> that I
>> >> >would have done if I were to include test information
>> about a type glass
>> >> in
>> >> >a book : ) But wait, that is what I DID back in 1992. It
>> appears in my
>> >> book
>> >> >on platinum printing. I don't site all the data. But do
>> talk about why
>> >> and
>> >> >when one might benefit from using it.
>> >> >
>> >> >
>> >> >This data also talks about the infrared quality of the
>> glass. I have not
>> >> >studied gum like I have studied platinum/palladium
>> printing. It may be
>> >> that
>> >> >Judy's experience with Starphire has something to do with
>> other
>> >> >characteristics of the glass that are not beneficial to
>> the chemistry she
>> >> >used.
>> >> >
>> >> >
>> >> >At this moment, I can't lay my hands on them which does
>> bother me. I
>> >> took
>> >> >them out of my notes to make copies for some students and
>> can't locate
>> >> them.
>> >> >I do however, have the data for the 4mm which is what
>> Sandy googled.
>> >> >
>> >> >I will however, be glad to post PDF's of the documents
>> after I receive
>> >> them
>> >> >in the mail. The faxes are OK, but I'd rather wait at
>> least until I have
>> >> a
>> >> >chance to print them with my higher quality printer. I am
>> sure she'll fax
>> >> >them to you too Sandy.
>> >> >
>> >> >The PPG web site that I posted last night has their phone
>> number. I
>> >> suggest
>> > > >calling them.
>> >> >
>> >> >
>> >> >
>> >> >
>> >> >Eric Neilsen Photography
>> >> >4101 Commerce Street, Suite 9
>> >> >Dallas, TX 75226
>> >> >214-827-8301
>> >> >http://ericneilsenphotography.com
Received on Fri Nov 18 14:04:57 2005