nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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...broke the clip off a green fluorescent ball-point pen and tacked it onto the field stop of 25mm eyepiece and viewed the sun in my new PST CaK this morning. Eureka it works! - the now green sun at least 10 times brighter [than the ultra dim normal blue CaK image] and easy to focus the limb but little detail visible through the turbid 1mm thick clip. Ok CaK guys - get experimenting. 
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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bill-in-forres
member
Reged: 06/19/05
Posts: 85
Loc: Forres, Scotland
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Congratulations, Maurice.
I'm sure this story has a long way to run!!
Bill
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Clear skies,
Bill Leslie
57.6degN 3.6degW
ETX90RA + Thousand Oaks white light filter
Helios 8" Dob.
Orion 20x80 binos on parallelogram mount.
PST on Astro3 equatorial mount
Williams Optics Binoviewers + Harry Siebert OCA for PST
http://www.sigma-astro.co.uk/
http://www.spacegazer.com/
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LarryAlvarez
Carpal Tunnel
Reged: 08/12/05
Posts: 2786
Loc: Texas
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I wonder if the green in the plastic is adding to the filtering of details. You could try melting it and making it thinner. Or if you made a small slice on the side of the eyepiece you could use it as a device for focusing and then remove it when the focusing is perfect. Clear Skyz, LA
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My Solar Website
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AstroRon
Pooh-Bah
Reged: 05/13/05
Posts: 1345
Loc: Maine Coast
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Would a light green filter work OR does it have to be flourescent? (I don't have a CaK to try)
Best,
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Ron, KF1H
PST/PSM40, ETX-125, Lunt 60mm/BF1200 on order
http://mysite.verizon.net/KF1H
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MikeTaormina
Pooh-Bah
Reged: 12/15/05
Posts: 1132
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Hi All,
I tried a small translucent fluorescent color "bingo" chip from one of my kids games, but the image through it was too blurry to see detail. If we could only get a really thin, more optically perfect piece of fluorescent colored material, it would work much better.
Mike
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http://www.pbase.com/miket883/solar
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nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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Quote:
Would a light green filter work OR does it have to be flourescent? (I don't have a CaK to try)
Best,
Thanks Bill, Larry and Ron. To Ron's query - the material for the 'screen' must fluoresce and convert near-UV [=CaK] to a longer wavelength like green light that the eye is more sensitive to. A green glass or plastic material will not work unless the pigments within it fluoresce. The domestic fluorescent tube works on the same principle. 
Larry - I don't think a fluorescent pen clip [or the body of the pen itself] can be pushed further beyond confirming a principle. I'm continuing to experiment with other suitable materials that fluoresce and will keep those interested duly posted.
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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Jim Shaffer
member
Reged: 10/10/04
Posts: 83
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I wonder whether a piece of "Vaseline glass" (an antique glass tinted yellow-green with uranium oxide) would work. It should be far enough from your eye to reduce the beta-particle count, I don't know how hot it is in gamma 
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nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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Quote:
I wonder whether a piece of "Vaseline glass" (an antique glass tinted yellow-green with uranium oxide) would work. It should be far enough from your eye to reduce the beta-particle count, I don't know how hot it is in gamma
Best avoid ANY material that MAY be radioactive near the eyeball or any body tissue for that matter
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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Caver451
member
Reged: 01/12/05
Posts: 91
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Quote:
I wonder whether a piece of "Vaseline glass" (an antique glass tinted yellow-green with uranium oxide) would work. It should be far enough from your eye to reduce the beta-particle count, I don't know how hot it is in gamma
Biggest danger from uranium oxide is alpha, however you really don't want alpha particles hitting your eye. If placed on the side away from your eye, all the alpha particles should be blocked. A piece of paper can block alpha.
Beta, on the other hand, can travel several feet in air and would likely go right through your eyepiece. Not much beta from the uranium glass (Uranium is primarily an alpha emitter) but any beta in your eye is a big no-no. It causes cataracts and potentially other nasties.
I would suggest a better option would be to spray a thin coating of "flourescene" dye (its green) on the back of a small piece of optical quality glass.
-Caver
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nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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Quote:
Quote:
I wonder whether a piece of "Vaseline glass" (an antique glass tinted yellow-green with uranium oxide) would work. It should be far enough from your eye to reduce the beta-particle count, I don't know how hot it is in gamma
Biggest danger from uranium oxide is alpha, however you really don't want alpha particles hitting your eye. If placed on the side away from your eye, all the alpha particles should be blocked. A piece of paper can block alpha.
Beta, on the other hand, can travel several feet in air and would likely go right through your eyepiece. Not much beta from the uranium glass (Uranium is primarily an alpha emitter) but any beta in your eye is a big no-no. It causes cataracts and potentially other nasties.
..don't need to go down this path in this application eg conversion of 'invisible' [for some!] light to visible.
Quote:
I would suggest a better option would be to spray a thin coating of "flourescene" dye (its green) on the back of a small piece of optical quality glass. -Caver
Precisely the need - I'm working on it
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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molniyabeer
Carpal Tunnel
Reged: 01/08/05
Posts: 1824
Loc: Central Coast, California
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For a mineral solution (and assuming you have access to some polishing gear...) fluorite from the Weardale valley in England is about the most fluorescent stuff there is. Some will actually fluoresce visibly in daylight. The Rogerly mine is famous for coke-bottle green glassy clear cubes up to 1/2" or more. If you could grind down and polish a piece of that you might have some luck. It is particularly sensitive to LW UV (around 350-370 nm). eBay often has samples for sale in the Fluorescent Mineral section and the Yahoo Group for fluorescent minerals may have a dealer/collector who could supply suitable material.
Cheers.
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Steve
10" Hardin DSH, StarMax 127mm Mak, PST H-a
Oberwerk 11 x 70 binocs, Tasco 10 x 50 binocs
Santa Maria Clear Sky Clock
Figueroa Mt Clear Sky Clock
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nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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Quote:
For a mineral solution (and assuming you have access to some polishing gear...) fluorite from the Weardale valley in England is about the most fluorescent stuff there is. Some will actually fluoresce visibly in daylight. The Rogerly mine is famous for coke-bottle green glassy clear cubes up to 1/2" or more. If you could grind down and polish a piece of that you might have some luck. It is particularly sensitive to LW UV (around 350-370 nm). eBay often has samples for sale in the Fluorescent Mineral section and the Yahoo Group for fluorescent minerals may have a dealer/collector who could supply suitable material.
Cheers.
That's interesting Do I assume the light, on fluorescence, radiates inefficiently in all directions. 
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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molniyabeer
Carpal Tunnel
Reged: 01/08/05
Posts: 1824
Loc: Central Coast, California
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[quote
That's interesting Do I assume the light, on fluorescence, radiates inefficiently in all directions.
I would assume it would radiate in all directions, however if you have a thin piece and the image is focused on it, you might be able to see the image. Could be fun to try but I don't have access to the lapidary equipment needed to give it a go...
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Steve
10" Hardin DSH, StarMax 127mm Mak, PST H-a
Oberwerk 11 x 70 binocs, Tasco 10 x 50 binocs
Santa Maria Clear Sky Clock
Figueroa Mt Clear Sky Clock
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JAT Observatory
Space Freak
Reged: 02/20/05
Posts: 5402
Loc: Eastern PA
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I think you will find a simple solution to this is a green highlighter type marker. They are flourescent and can be easliy applied to an old eyepice for testing. If I had access to my Cal-K PST I would try it as I have an old eyepiece that would be prefect for testing.
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-Marcus
Earth is the solar system's ghetto
http://jatobservatory.org
12" LX200R on a Paramount ME
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WahHK
sage
Reged: 02/24/06
Posts: 259
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Why doesn't Coronado produce "flourescent CaK eyepieces" if this simple way works?
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http://wahwah.dyndns.org:8080/gallery/main.php
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nytecam
Post Laureate
Reged: 08/20/05
Posts: 4548
Loc: London UK
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Quote:
Why doesn't Coronado produce "flourescent CaK eyepieces" if this simple way works?
Is your statement [..this simple way..] true?... and how do expect them to react to something only recently discussed here in last couple of days?
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+DS-2090+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9/Lodestar/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-spectro page
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cambert
sage
Reged: 07/21/04
Posts: 217
Loc: Chartres, France
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(re-posted)
fluoresceine, a liquid used in ophthalmology, emit green light when lighted by blue light ("cobalt bue") but I don't know if it react to violet. I'll make some experiments this afternoon.
Even if it works, what is the next step ? Paint glass neutral filter wiht it ?
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Cambert
Coronado Maxscope 40 telescope
10" Meade SCT
16" Meade Lightbridge
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Caver451
member
Reged: 01/12/05
Posts: 91
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Quote:
(re-posted)
fluoresceine, a liquid used in ophthalmology, emit green light when lighted by blue light ("cobalt bue") but I don't know if it react to violet. I'll make some experiments this afternoon.
Even if it works, what is the next step ? Paint glass neutral filter wiht it ?
It's used for a lot of things. "Cavers" use it to trace water flow through a cave system, since the die is biologically safe.
CaK is centered around 393.4 nm, which is within the excitation range of fluorescein. It should excite at that wavelength, as well as into the near ultraviolet. I've also used a N2 laser (337.1 nm) to pump rhodamine 6G, which might also be another candidate. Rhodamine stains like heck and is rather toxic, and fluorescein may be easier to get a hold of.
These are probably the easiest options for us humble hobbyists. 
-Caver
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DAVIDG
Pooh-Bah
Reged: 12/02/04
Posts: 1270
Loc: Hockessin, De
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Oh Boy, it looks like I got something going here ! I knew this would work because I've used it in the past on other types of my research. All that is needed is a thin coating from a Day Glow yellow green marker on a clear filter that one screws into the eyepiece. I'll do a little research and see if I can find a dye that absorbs exactly at 395nm and re-emits in the visible. These types of dyes are used all the time as molecular probes in chemist. Also Wah is correct that many "plexiglasses" like the yellow and pink colors are absorbing UV and re-emitting in the visible.
Here is another thought,that I wonder if Coronada has looked into. They seem to be using a achromat as the objective. I know that is the case in the Ha PST version. The lens is cemented together with a UV curable adhesive. May times these materials also absorb strongly in the near UV even after curing. This one reason I use quartz optics in my research. Just wondering if the adhesive in the lens and also the coatings on "standard" eyepieces isn't absorbing at 395nm and the dimming the image farther ?
- Dave
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Homemade 'scopes 8"f/7,6" f/5", 6"f/4, 4.25" Schief. 60mm Coronagraph,60mm H-alpha system, 4.25" White-light Solar Newtonian,solar spectroscope, 4.5" f/16 Schupmann Medial refractor, 14 Stellafane awards 7 in optics
Engineering = Taking what you have and making what you need.
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BobH1357
member
Reged: 01/15/05
Posts: 74
Loc: San Jose, CA
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I use pieces of fluorencent glass everyday to be able to see light at 364nm. I'll get the number of the glass when i go in to work this morning. It's about 1mm thick, cheap, anf fluorences a nice yellowish green. Although the dye is uniform throughout the glass, UV images focused on the input surface are excellent!!! You Ca-K guys are in for a REALLY big treat!! 8^)
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