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Curious - does using dew heaters make refocusing incrments smaller?
I am a big one for data based analysis - so I was curious of a trend I noticed over the last 2-3 nights.
I normally refocus my scopes around every hour or every degree the temperature falls - according to each scopes focusers thermometer.
Now I have noticed since using dew heaters (set at about 45% power) for both APT and SGP the focus steps seem smaller relative to each degree the temperatures fell. So from say from 15 - 16 degrees at sunset to 7 - 11 degrees at 1am the focus changes may have been around 30 - 40 steps (per degree temperature change) - before the use of dew heaters down to maybe 10 - 20 steps per degree since using dew heaters.
I know the need to refocus is a factor of both the scopes shrinking and the glass changing and the air itself refracting differently - but I am wondering if gently warming the melt around where the front lens cell is - not only helps the glass but warms the tube (even though its only the lens cap and it likely bleeds some warmth into the tube itself).
Has anyone else experienced this - or is it simply my data set is too small over a few nights - and I am seeing a localised anomaly?
Curious, Matt
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