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Quick Q on secondary mirror size (Newtonian)

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#1 InkDark

InkDark

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Posted 19 June 2019 - 08:19 AM

Hi,

 

The listed specs of secondary are referring to the length or the width of mirror?

 

Thank you



#2 rachnoman

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Posted 19 June 2019 - 08:29 AM

Width or minor axis (MA) for a diagonal mirror.


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#3 InkDark

InkDark

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Posted 19 June 2019 - 08:48 AM

Thank you!

 

I always thought it was the length, but I came across some numbers that made me doubt. You have now removed that doubt.

 

I guess that the minor axis represent more faithfully the full circle of the secondary once it is collimated and viewed from the focuser.


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