Here is a fun little item that might be useful, and it is inexpensive ($7.25). Would it possibly give enough data if you analyzed the light coming through the glass as a comparison? It shows a color band of the light and numbers (I have only looked through one in fun) but no scaled readout like a spectrophotometer.
Description below; to see photo or order go to:
http://www.sciencekit.com and enter 16525-00 in the search box.
*********************
QA Spectroscope
Measure wavelengths of light from 4000 Å to 7000 Å with accuracies of ±50 Å.
The low price means that every student can have one of these spectroscopes, and the laser-produced diffraction grating (which produces excellent results) means that every student will want one.
This hand-held spectroscope is one of our best-selling products partly because it allows students to analyze light in both emission and absorption spectra. The scale is 37 mm long. Developed by Werner Schultz.
Includes: unbreakable plastic case, laboratory suggestions and instructions.
WW1652500 Spectroscope, Quantitative Analysis (QA) $7.25
********************
JT
-- Judy Rowe Taylor Mukilteo, WA Art is a voice of the heart, a song of the soul. www.enduringibis.com jude.taylor@comcast.net or judyrowetaylor@enduringibis.com
Date: Thu, 17 Nov 2005 14:24:47 +0000
From: Sandy King <sanking@CLEMSON.EDU>
Subject: Re: BL vs BLB tubes for cyanotype
To: alt-photo-process-l@sask.usask.ca
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Hi Mark,
Yes, a spectrophotometer would be the thing we need. If we all had a
spectrophotometer we could take all of the speculation and guesswork
about the transmission properties of glass out of the equation.
You see them on ebay from time to time, but they usually go for more
than I am prepared to spend for something that I probably would not
use but once or twice a year. But you might find one very useful for
your tests with digital negatives from various printers on different
substrates in conjunction with PDN.
Sandy
>Sandy,
>
>What instrument would one use to measure the spectrum of light
>passing through some material such as the glass you are talking
>about? Where might one get access to one? Would my doctor's
>colonoscope work?
>
>Would it be a Spectrophotometer?
>
>
>Thanks,
>Best Wishes,
>Mark Nelson
><http://www.precisiondigitalnegatives.com/>Precision Digital Negatives
>PDNPrint Forum @ Yahoo Groups
><http://www.markinelsonphoto.com/>www.MarkINelsonPhoto.com
>
>In a message dated 11/16/05 9:18:48 PM, sanking@clemson.edu writes:
>
>>Well, not quite 909%. The intended percentage was 90%.
>>
>>Sandy
>>
>
>
>
>
>
>
>Best Wishes,
>Mark Nelson
><http://www.precisiondigitalnegatives.com/>Precision Digital Negatives
>PDNPrint Forum @ Yahoo Groups
><http://www.markinelsonphoto.com/>www.MarkINelsonPhoto.com
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<html><head><style type="text/css"><!--
blockquote, dl, ul, ol, li { padding-top: 0 ; padding-bottom: 0 }
--></style><title>Re: BL vs BLB tubes for
cyanotype</title></head><body>
<div><br></div>
<div>Hi Mark,</div>
<div><br></div>
<div>Yes, a spectrophotometer would be the thing we need. If we all
had a spectrophotometer we could take all of the speculation and
guesswork about the transmission properties of glass out of the
equation.</div>
<div><br></div>
<div>You see them on ebay from time to time, but they usually go for
more than I am prepared to spend for something that I probably would
not use but once or twice a year. But you might find one very useful
for your tests with digital negatives from various printers on
different substrates in conjunction with PDN.</div>
<div><br></div>
<div>Sandy</div>
<div><br></div>
<div><br></div>
<div><br></div>
<div><br></div>
<blockquote type="cite" cite><font face="Geneva" size="-1"
color="#000000">Sandy,<br>
<br>
What instrument would one use to measure the spectrum of light passing
through some material such as the glass you are talking about?
Where might one get access to one? Would my doctor's colonoscope
work?<br>
<br>
Would it be a Spectrophotometer?<br>
<br>
<br>
Thanks,<br>
Best Wishes,<br>
Mark Nelson<br>
</font><a href="http://www.precisiondigitalnegatives.com/"><font
face="Geneva" size="-1" color="#0000FF">Precision Digital
Negatives</font></a><font face="Geneva" size="-1" color="#000000"><br>
</font><font face="Geneva" size="-1" color="#808080">PDNPrint Forum @
Yahoo Groups</font><font face="Geneva" size="-1" color="#000000"><br>
</font><a href="http://www.markinelsonphoto.com/"><font face="Geneva"
size="-1" color="#0000FF">www.MarkINelsonPhoto.com</font></a><font
face="Geneva" size="-1" color="#000000"><br>
<br>
In a message dated 11/16/05 9:18:48 PM, sanking@clemson.edu
writes:<br>
</font>
<blockquote type="cite" cite><font face="Geneva" size="-1"
color="#000000">Well, not quite 909%. The intended percentage was
90%.<br>
<br>
Sandy</font><br>
<font face="Geneva" size="-1" color="#000000"></font></blockquote>
</blockquote>
<blockquote type="cite" cite><font face="Geneva" size="-1"
color="#000000"><br>
<br>
<br>
<br>
<br>
<br>
Best Wishes,<br>
Mark Nelson<br>
</font><a href="http://www.precisiondigitalnegatives.com/"><font
face="Geneva" size="-1" color="#0000FF">Precision Digital
Negatives</font></a><font face="Geneva" size="-1" color="#000000"><br>
</font><font face="Geneva" size="-1" color="#808080">PDNPrint Forum @
Yahoo Groups</font><font face="Geneva" size="-1" color="#000000"><br>
</font><a href="http://www.markinelsonphoto.com/"><font face="Geneva"
size="-1"
color="#0000FF">www.MarkINelsonPhoto.com</font></a></blockquote>
<div><br></div>
</body>
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Received on Thu Nov 17 14:43:01 2005
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