[ATM] Calculating Focuser Length and Travel

[alaudet at timminsastronomy.com (Al Audet)]

Thanks Mike,

Ok...that makes more sense to me.  If I let the focuser extend an inch 
into the tube that would make my focuser height 3.25" with travel of  
1.75".  Does that sound correct?
I guess from there on it would just be a matter of finding something 
that makes sense.  Perhaps 3.5" height with 1.5" travel, which means 
about .75 inch of the focuser inside the tube when fully racked in. I 
think at that height it would still be hidden (or at least partially) 
behind the baffle right before my hole opening. (9.156inch diameter 
baffle)  Can you tell I downloaded Newt?  :-)

BTW, I am also using a 10 inch tube.

Thanks

Al

>
>Usually racked in means "all the way racked in" not just to the edge of the
>tube.  .75 inch might not be enough travel to focus all your eyepieces.
>
>Sometimes this means the focuser tube will extend into your tube for a
>distance.  
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