Posts Made By: Anthony Vitali

Hello,

I am starting to put together a project to make an objective. I have a 5.5 inch pressed blank set that I would like to use. Unfortunately I am uncertain of the glass documentation.

The plano/concave blank has " F621" written on it.

The convex/convex blank has "BSC" " 1.517" " 64.5" written on it.

I found a reference table for glass types on the Newport Glass web site. In that list I find a reference from Hoya for BSC2 with optical data of 517645. Using the guide information for the table makes me think that this is the same material I have?

Also, I found a reference to a Hoya glass known as F6 with optical data of 636353 but nothing as F621. Could F6 and F621 be the same?

Does anyone know a site with a more extensive list of glass types?

Does anyone have this glass and associated optical data?

Any feedback on how to ID this glass would be very appreciated.

Thank you,

Anthony

Are you talking about a lens in which the index of refraction for each element changes with radius from the center?

What would a 8in F5 lens cost?

bill west said:

anybody know what distributor will sell me a sheet of kydex. I live in south jersey. Even a 1/4 sheet would do 2x4. I'm making a truss scope and I would rather use kydex because of the weight and durability.

I have purchased ABS from TAP Plastics. Google TAP Plastics for more information.


They sent the ABS I ordered very quickly and the 24 x 48 sheet was not too expensive.

Good luck,

Anthony