Projection Screen

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ANTHONY54
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Projection Screen

Post by ANTHONY54 »

Does anyone know where I can get a projection screen for an old 3inch Vixen.

Thanks.
Anthony.
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Post by @@ »

soz mate
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ANTHONY54
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Post by ANTHONY54 »

OOOPS,
That is a projection screens for solar astronomy.

Anthony.

:oops:
Brian
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Post by Brian »

Hi Anthony.

It seems that some small telescopes are sold with a solar projection screen included, but as "add-ons" these things seem rarer than hen's teeth.

An alternative would be to make a safe solar filter to fit your telescope using Baader Astrosolar Safety Film. The ND=5 version cuts down solar energy entering your telescope by 99.999% so you can look at the Suns image at full aperture using normal eyepieces.

For instance, see Here

ATB,
Brian
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mike a feist
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Post by mike a feist »

From some experience we found that the screen supplied with a refractor really was too small. During solar eclipses and other solar observing we found it best to project the image of the Sun into a cardboard box (with white card stuck inside the bottom) set up at an angle on the ground. maf
LeoLion
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Post by LeoLion »

Hi Anthony , You could try 'A Plantpot Solar Projector' as in this article by Cliff Shuttlewood http://www.britastro.org/iandi/shuttlewood.htm . You should also Google for Sun Gun for another screen device for Solar .
When I read your post I had a quick look for TAL telescopes and bits & bobs on eBay as they used to come with a screen as standard. Hope this is of some help,
Len E
brian livesey
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Post by brian livesey »

Just to say, Anthony, that cemented eyepieces shouldn't be used for solar projection, the intense heat will damage the balsam.
I have three Huygenian eyepieces that I use for projecting the Sun into a light plywood box. Huygenians work best with f.12 upwards 'scopes; Ramsdens work well with shorter focal ratios.
Another point to make is that I slackened the field-lens retaining ring slightly in each eyepiece to allow for expansion of the lenses when exposed to heat, otherwise there's a risk of cracked lenses.
brian
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