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Use of vintage eyepiece sun filters.

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228 replies to this topic

#226 Joe Cepleur

Joe Cepleur

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Posted 07 April 2016 - 10:22 AM

Sun filters were expected to be used with Huygenian eyepieces where the focal plane is actually inside the eyepiece and so the filter is far from it and probably not subject to great heat concentration.

 

In theory, perhaps, and an interesting point; yet, in the history of broken Sun filters, surely many broke while used with the Huygens sold with many classic telescopes. Using an eyepiece filter with a Huygens eyepiece places the filter within an inch or two of the most concentrated rays, exposing it to far more heat than, for example, a perfectly safe filter over the objective. One hopes readers would not misinterpret this as meaning it were okay to try using an aging eyepiece Sun filter with a Huygens eyepiece. Don't do it. Not worth the risk! 


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#227 Mr Magoo

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Posted 04 May 2016 - 06:02 PM

Not for the squeamish maybe, but the proof is in the seeing so to speak. http://www.scienceal...ugh-a-telescope


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#228 Rich (RLTYS)

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Posted 05 May 2016 - 05:36 AM

Most interesting but absolutely true.

 

Rich (RLTYS)



#229 saemark30

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Posted 29 July 2016 - 09:53 AM

Does anyone have a sun filter of 1.25" size they can donate for a experiment?




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