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    Default Collimation of SCT (ACF)



    I am in the lucky position to have two 8" LX90ACF OTA's. My problem is that I am having problems collimating one of the two : The star test pattern changes between intra and extra focus You could have a near perfect pattern in the one and then the pattern could be skew in the other. Only the one tube has this problem. Should I rather adjust it on the infocus side or extra focus side? Having said this when I compare them on the same optical target like the trapezium in the Orion nebula I can't see much of a difference. Is it possible that the corrector plate is misaligned ?
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    Default Re: Collimation of SCT (ACF)

    I can't help you but it dose sound like there is some miss alignment ,i get the same problem on my newt with in and out focus on a star test, few people here are pretty good at collimating sct,s someone will come along and help.

    you might want other tools to collimate your scope other then a using star test,i've had success and failures using this method , sct's/newts can be rather complicated in collimating in that matter , things like secondary tilt/alignment/focuser alignment tilt all need to be adjusted

    but "collimation" close enough is good enough i say

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    Corrector,
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