To take photo's of the stars even modern digital camera's require exposure times from 10's of seconds to a few minutes or more. However any exposure over a few seconds, especially with a telephoto lens, will show 'star trails' (caused by the stars 'smearing' as the Earth turns). To take 'pin sharp' photo's requires a camera mount that counteracts the movement of the Earth. One such (that can be constructed using basic wood-working skills) is the 'Barn Door' or 'Haig Mount' and is described here.
Although the basic Barn Door mount can be 'driven' by hand, I also describe how a simple electro-mechanical drive can be constructed without the need for any complex electronics. To minimise battery usage, I then finish up with a more complex PWM driven system
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+ Field of view == Latest changes (modified 29th May 2018 14:43.)
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