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Resolution Charts for Testing?

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#1 Auburn80

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Posted 15 July 2019 - 11:51 AM

My apologies. I did some additional searching via Google and I think I'm just going to do a competitive test using a common target.

Edited by Auburn80, 15 July 2019 - 12:55 PM.


#2 Eddgie

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Posted 15 July 2019 - 02:04 PM

Here are some of the very best MTF test targets available.

 

http://www.normankor...rials/MTF5.html

 

My recommendation is to pick the ones you think will be the best for the focal ratio of your instrument and have them professionally printed.  This does not cost that much at all.

 

Again, I recommend that you find the right frequency for your instrument by focal ratio and your test location. Most telescopes are going to require a frequency between 200 and 500 line pair (finest resolution) at the focal plane. to really get the full range for MTF.

 

This is the problem with most test charts.. You have to have them at impractical distances when testing telescopes.  

 

Anyway, these are the best because a sinusoidal wave of varying frequency is exactly what is used for MTF evaluation test charts.   The use of solid alternating lines (Solid black/Solid white) will not give as fine of an evaluation as using the sinusoidal charts will. 


Edited by Eddgie, 15 July 2019 - 02:10 PM.

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