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 Post subject: Tutorial on Using a Polariscope
PostPosted: Fri Feb 24, 2012 12:46 am 
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Joined: Sun Oct 16, 2005 12:22 pm
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Location: San Francisco
This tutorial was compiled by Starla Turner, FGA, GG:


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 Post subject: Re: Tutorial on Using a Polariscope
PostPosted: Fri Feb 24, 2012 2:24 pm 
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very nice informative video, thanks for sharing

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 Post subject: Re: Tutorial on Using a Polariscope
PostPosted: Mon Jun 25, 2012 10:12 am 
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This forum just keeps getting better and better.. (Thanks Barbra) :wink:


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 Post subject: Re: Tutorial on Using a Polariscope
PostPosted: Mon Jun 25, 2012 10:40 am 
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Oh Starla is just the coolest.....if you ever get an opportunity to take a class from her, jump on it.


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 Post subject: Re: Tutorial on Using a Polariscope
PostPosted: Fri Apr 08, 2016 11:23 pm 
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kylochua wrote:
This forum just keeps getting better and better.. (Thanks Barbra) :wink:


Yes, I agree. Thanks for sharing the videos. I've been watching the other videos of her and they're very helpful. I'm totally new at this but this really makes it much easier to follow. Thanks again. Any chance you can share more videos?


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 Post subject: Re: Tutorial on Using a Polariscope
PostPosted: Sat Apr 09, 2016 8:22 pm 
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Just a bit of a correction. Light polarized at 45 degrees from the Polaroid filter will have a 50/50 chance of going thru - but after it goes through it will be polarized in the same direction as the filter. Light that is 90 degrees off has no chance of going through.
Going through the calculations, a perfect polarizing filter will let 1/2 of the light through. And strangely if you have 3 Polaroid filters, in this order: horiz, 45 degrees, vertical, light DOES get through. Half goes through the first filter and is polarized horizontally. Half of that makes it through the 45 degree filter, and half of that goes through the vertical filter, so 1/8 of the original light goes through. But if you remove the middle filter, NO light gets through.

Strange games with Polaroid filters.


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