Quote:
Originally Posted by pvelez
Here's the thing Fred - when it calibrates, I have a nice red L. When it doesn't, it moves only a few pixels - in x rather than y. Sometimes it won't move at all. I judge this from the x,y co-ordinates after each exposure listed below the "moving telescope" list to the right of the guide screen.
And it does this in the same session in different parts of the sky.
Not sure about the guide rate - will check on the lappy when I get home this evening.
Pete
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If the move is too big, and 50secs sounds huge, then the star can go off the screen, or/and it picks up another star in view for the next step (or end of present step)if there are several stars nearby. Also, it can loose the star in a move and pick a hot pixel, which may be right at the beginning of the move and then show a very short red line, or none at all. You should be using the simple dark feature for the guide cam to fix a noisy pic, especially for 2secs or longer guide exposures. If yr guide cam doesnt have a shutter, then DL will ask you to cover the cam for dark taking. If you dont cover for the dark, the dark will be useless and no help.
The screen stretch does not affect cal as far as I know, but cranking stretch up can be handy to see if noise is a problem, but for reliable cal/guiding the star should be bright (without stretching), no noise and no other stars nearby during cal. Cal can be done away from the object on an isolated bright star before guiding on the object, a clean cal star is more important than the guide one.