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Old 10-07-2012, 05:08 PM
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peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: SE Tasmania
Posts: 4,573
The new tab layout looks good Dave.

I've been playing with the temperature compensation and with the filter presets tonight and have a question about how these interact.

I would have thought the desired behaviour would be to allow the temperature compensation to take care of the absolute position during the night and for the filter offset to look after the difference from one filter to the next ie:

1.I focus on the Lum filter at the start of the night at say absolute position 3500 and set this as reference. Offest for this filter (filter 1) = 0
2. Temperature compensation moves the absolute position as the temperature drops (in my case the absolute position is increasing=focuser in). Assume the absolute position drops by 20 steps to 3480.
3. I change to the next filter say red with an offset of 10 steps relative to the lum at constant temp by clicking go for that filter. I would expect the absolute position would move to 3480+10=3490.

I think what is actually happening is the focuser moves to ref+10=3510. This means I would now need to refocus for filter 2 as the reference position was set at a higher temperature. The same would apply for each filter change if the temperature changes.

Let me know if I've got this all wrong
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