Mike Traub(Mr. Congeniality): I've learned that I don't suffer from insanity, I enjoy it!:Shipfitters mottos; Cut to suit, pound to fit, paint to hide!: If it dosen't fit get a bigger hammer!......Retired and BROKE!!!!!!!!: The Maypole Observatory.
CPC1100, Celestar8, PST plus club access to a 24" Boller&Chivens, C16, and many more toys.
__________________________________________________________________________________________________________________Sheet Metal Worker/Welder Indiana Astronomical Society 6" f/10 home brew dob, Quantum 4, 90mm Apex Mak, Criterion RV-6, Criterion RV-8, Coulter Odyssey 1 13.1", Meade 16" Lightbridge, Sears Discoverer 4-6305A, Manon 60mm (The Marsha Scope), Towa 11T, Tasco 10TE
Homemade 'scopes 8"f/7,6" f/5", 6"f/4, 4.25" Schiefspiegler,60mm Coronagraph,60mm H-alpha system, 4.25" White-light Solar Newtonian,solar spectroscope, 4" f/12, 4.5" f/16 & 6" f/12 Schupmann Medial refractors, 4" Celestar, 19 Stellafane awards 9 in optics Engineering = Taking what you have and making what you need.
Quote: I have a number of old military Erfles include one that looks very similar to yours which also has the amber colored glass. I have tested it for radioactivity and it IS mildly radioactive. It now sets in a thick metal box and I will never use it. The amount of radioactivity coming off of mine is not going to cause me to glow in the dark but if I could I view thru and use it on a regular basis it would increase the odds of me getting cataracts. - Dave
Orange tube C-8, SV Nighthawk, Tasco 76.2mm x 1200mm, Vixen RS150
Orthos, Plossls, RKEs, ES82s, ES68s
Voyager Mount, CG-5
Curator, BSU Observatory www.bridgew.edu/observatory
Wife, kids, dog.Views with glasses: astigmatism and major floaters.Orion StarMax 90mm Mak-CassPorta II45mm 35° | 40mm 43° | 35mm 49° | 28mm 45° | 25mm 50° | 15mm 58° | 11mm 82° | 10mm 50° | Shorty Plus 2xVestil CPRO-800LP observing chairVarious binoculars in the "bang-for-buck" category
Observing the Sun with complex optical systems since 1966, and still haven't burned, melted or damaged anything. Not blind yet, either!
Quote:Looks like thoriated glass. Should be safe to use as its radiation is alpha decay which is non-penetrating. This radiation will yellow the glass over time, though this is reversible: leave it in the bright sun or under a UV source for some period of time and it should clear up. Although such "radioactive glass" is safe to handle, proper disposal is another matter.
1961 8" F8 Criterion Dynascope Deluxe (dob mount) C6, Celestron GT102 ,PST Vixen Ascot 10x50,12x50 Pentax PCF WP II Denk big easy pairs of TV 32mm,11mm plossls, celestron 25mm plossl, 17mm sterling, 9mm X-cel LX, 20mm superviews AT 17mm 70 AF, 8mm AT Paradigm, AT 12mm plossl ES 82* 6.7mm,11mm,14mm,ES 68* 24mm 2.25x Ultima Barlow VT 25mm Ortho, BCO 10mm,18mm, TV Plossl 15mm,26mm, GSO 40mm plossl, 20mm sterling 1 dog, 3 cats, 2 sons and a beautiful wife
Quote:Not all surplus Erfles are radioactive. There was a thread about this before and I was curious so I took it to the local Thyrocat (Iodine 131 treatment center for hyperthyroid felines) and used a geiger counter on it. The EP was completely inert, nothing detected at all. The glass on mine is clear (and uncoated.) I'm sure there is some truth to the radioactive "myth".
12 Skywatcher Collapsible Dobsonian (coming soon, two more days, be here Tuesday)
Celestron C102 HD " Carl"
Scope brand 60mmx 700mm " widger scope"
Celestron Comet catcher(orange tube)"Scott"
60mm Telescope Club
Quote:Cool! So it's post-war atomic tech in an eyepiece! I did a quick search on "thorium glass" and came up with this wiki:http://camerapedia.wikia.com/wiki/Radioactive_lensesThe wiki says thorium oxide, like fluorite, has properties of high refractivity and low dispersion. The wiki goes on to say that although the radiation level is very low it can pose a danger specifically with eyepieces, where the eye is exposed directly with no skin as a barrier. The wiki also mentions the use of several days of UV sunlight to clear up yellowed or browned glass elements.Man, if it was an F-mount (which I doubt), I'd totally want one of those radioactive 35mm f/1.4 Nikkors!
Far out in the uncharted backwaters of the unfashionable end of the Western Spiral Arm