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Just to clarify. I didnt mean that 15- 20mins was the exposure length. But i think they were more referring to thats the period of time where each of your exposures is still capturing the same frame each time. After that time fram you start to get drifting of the picture. Or at least that was how i was understanding it.
At the moment with my dodgy polar alignment (cant actually see the pole from my location) ive still been able to get 2 min subs at short focal lengths. I think 45sec to 1 min at 200mm is my best so far. (Which i think is ok for a first time barn door tracker).
And why would driving the doors apart not track the same as pulling together. I get that the load is kind of working against the push out. But surely once the motor is moving and up to speed it should be the same?? I am using an arduino for speed control of the stepper. Gears are one to one ratio at one rpm.
I would like to work out some error correction and program that in but i havent found a way to calculate my error as yet. (Any tips on this will be much appreciated).
Ive actually got a printable template with holes pre marked etc to help with accuracy if anyone would be interested. I just glued it to some wood and drilled with the markings.
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