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Diagonal clear app

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#1 hakann

hakann

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Posted 20 March 2017 - 06:45 PM

I'll just reached this issue when calculation a diagonal, vs learn the math, draw it up, use of a paracorr and where EP comes into focus etc.

Lets say I might think how to set a minium diagonal.
If one draw a line from primary ( clear app ) to focal lenghts and one determate a L-distance.
Ok lets say it shows 7.5".
But if one draw lines and field stop in light cone included it means 8.25".

But from what I might realise now on diagonal's there are bevels on them to and one can't really use more than 90% out of them.

So even if I go on a 8" I will not be using or rely on more than 7.25", so I'm not get a 7.5" - as what I need even if I go 8".

Ok, so what is test show on used aperture on diagonals on high-end companys ?

I'm into a a waffle design as stiffer/lighter.
Thoose are in stock at even inches but of course one can do a special order or demand a clear app one need.
But I like to has test on them.

Before I thought using a lip at 1-2 mm radius - one would be ok.

Going on a to big diagonal means over 32%, and is that ok for a fast ex 25" visual Newton doing deep-sky.

Edited by hakann, 20 March 2017 - 06:52 PM.


#2 hakann

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Posted 21 March 2017 - 03:51 PM

I called Antares and they said 90% and that is Not including bevel.

Guess home made might be done at 100.


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