Back to Home

ATM Forum Message

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button
Home | Discussion Forums | Amateur Telescope Making | Post
Login
Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora
I Need Help Identifying Glass!

Forum List | Follow Ups | Post Message | Back to Thread Topics
Posted by Steve Fejes jsfejes@swva.net on August 2, 2000 21:36:59 UTC

I have three glass lenses from a large projection lens which I would like to turn into a refractor objective. They are 5" diameter. I have a good idea what the glass types are, but I want to be sure before I start to grind any glass.

I am planning on measuring the focal lengths at various wavelengths to I can know the dispersion of each glass. I have no light sources or filters which are acurate enough to do this with. So, I thought that I could use a street light which emits only certain wavelengths of light. There are High Pressure Sodium and Metal Halide lamps commonly used.

I need to find out what wavelengths are emitted by these lamps. I have not been able to find out which wavelengths are in these lamps. I did not find it on GE`s site or Sylvania`s either. Do you know were I can find out? Thanks

Follow Ups:

Login to Post
Additional Information
Google
 
Web www.astronomy.net
DayNightLine
About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
Unless otherwise specified, web site content Copyright 1994-2025 John Huggins All Rights Reserved
Forum posts are Copyright their authors as specified in the heading above the post.
"dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
are trademarks of John Huggins