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ATRC8 Primary (mis)collimation?

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#1 saadabbasi

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Posted 12 September 2013 - 12:43 PM

I've adjusted my RC8's moonlite focuser such that the laser beam falls on the center spot on the primary. I then adjust the secondary such that that the beam folds back on itself. All of this is spot on and I'm confident that the secondary is collimated as well as the focuser.

But when I attach the holographic attachment to my laser I get the following pattern. Notice that the reflection from the primary is slightly off-centered (note the small arrows). Does this indicate that the primary is not collimated properly?

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I would massively appreciate any advice on this!

#2 Jared

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Posted 13 September 2013 - 05:00 PM

The first step you took--where you adjusted your focuser such that the laser fell on the center spot of the secondary--would only have been appropriate if your primary was already collimated, which it may not have been. The laser missing the center spot can be because of either the primary not being collimated or the focuser not being collimated (or both). You don't know which was at the root of the initial problem.

#3 saadabbasi

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Posted 13 September 2013 - 07:54 PM

I see, Jared. So how should I proceed from here? I feel completely lost regarding this. The focuser and secondary are easy to adjust and I haven't touched the primary yet. If you could give some brief instructions I'd really appreciate it.






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