Re: [APML] Beep on ST4

[Matt BenDaniel <matt@starmatt.com>]

Massimo,

Yes, the ST-4 most often beeps due to guide star brightness diminishing. I think SBIG made a mistake in making the threshold too easy to trigger. The real problem is that the ST-4 can decide to stop tracking 83 minutes through your 90 minute exposure.

For that reason, when I start tracking, I always partially cover the front of the scope to reduce its brightness. After one cycle (a few seconds), I uncover the front of the scope.

Matt

At 11:53 AM 6/20/2002, Massimo Costa wrote:
>Hi all,
>from ST4 manuals I read that a beep during tracking means that the guide star drops in luminosity half value. Have I to consider it a fatal error? In other words, in that case it's better stop exposure or continue? Often, after beeps, redout values seem to be low as before. My mount is a G11 Gemini.
>Thanks for the attention.
>Massimo

--
Matt BenDaniel
matt@starmatt.com
http://starmatt.com


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