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Testing optical flats - The Raleigh Water test

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#1 Olivier Biot

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Posted 28 November 2010 - 09:52 AM

Testing optical flats - The Raleigh Water test

#2 BoriSpider

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Posted 28 November 2010 - 05:04 PM

FYI when I click on 'All Additions in the Last 30 Days'
link on the front page, then I click on link to this article,
the link doesn't work.

#3 BoriSpider

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Posted 28 November 2010 - 05:05 PM

lol.

And the link above doesn't have an article.

#4 bob71741

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Posted 28 November 2010 - 07:04 PM

Boris
click on the above link; then click on "download this article" to see and copy the "PDF"

#5 Olivier Biot

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Posted 28 November 2010 - 07:40 PM

This article is a PowerPoint slide show that was rendered in PDF so everybody could read it. There is no text version of the article.

There's the "Download this document" link at the top of the article where you can retrieve it.

#6 BoriSpider

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Posted 28 November 2010 - 08:47 PM

Ah, I see. tnx.

#7 MKV

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Posted 05 January 2012 - 03:19 PM

I just stumbled upon this post and Ed Jones' The Raleigh Water test article where he says with regard to the testing an optical flat against a spherical mirror (better known as the Ritchey-Common test) that it is "[g]ood for testing spherical power but not great for localized areas."

In fact, the Ritchey-Common test can provide excellent information for 'localized area' if, instead of a point source, a diffuse light source and a Ronchi screen or a Foucault test are used.

The Ritchey-Common test is a comprehensive quantitative and qualitative analysis tool if you have a single piece of optics of unknown radius of curvature, and have no master flat to check it against.

Mladen

#8 wzmek

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Posted 20 August 2014 - 11:14 AM

I agree with Mladen. I know that Bob Royce has made some large flats using the Ritchey-Common test.








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