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Old 15-08-2015, 05:27 PM
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gregbradley
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Join Date: Feb 2006
Location: Sydney
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Quote:
Originally Posted by rally View Post
What is the guide interval you are using ?

Guide exposure is a variable and it changes depending on the setup as well as seeing but generally 4-6 seconds on the PME and 5-6 seconds on the AP1600. I used to run 1 second with a Tak NJP, 3 seconds with a 1 second delay on PMX, sometimes just 3 seconds no delay or simply 4 seconds.

There is a great astrochannel interview with the developed of PHD2 and he goes over guiding in great detail.

Too short a guide exposure and you can chase bad seeing and lose SNR and make it hard to get a guide star. Too long and you are missing correcting PE especially any step segments of the PE. So guide exposure is not a set amount for a mount but more of a range depending on the current conditions.

Greg.
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