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Topic: Tilt only sensor for telescope. (Read 2 times) previous topic - next topic

mowcius

An accelerometer will not be accurate enough to measure the tiny accelerations - do you mean a gyroscope? :)

Senso

A gyroscope to read tilt?
A gyro gives you the rate of change but not the actual value, so when not moving it just gives you 0, so its of no use, a gyroscope with a resolution of 3.9mG/LSB like the ADXL345 is not enough?

mowcius

Oh I always get confused with them...

RuggedCircuits

A low-cost accelerometer will be noisy and not too precise but the OP said "the plan is to add a tilt sensor and roughly calibrate it to the tilt" so I figured a rough measurement from an accelerometer would be good enough.

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retrolefty

#9
May 24, 2011, 03:38 am Last Edit: May 24, 2011, 03:40 am by retrolefty Reason: 1
Quote
I have Maksutov Cassegrain and it suffers from "mirror flop." I.e. when you look at something low in the sky, the focus changes when you swing it to something higher in the sky. Thus a constant need to refocus arise when you change the angle of the scope.


Is this a commercial telescope or a DIY scope? You really should try and solve the root problem and fix the mirror flop. I've build a couple of reflector scopes in the distance past and a decent mirror mount design should not allow for primary mirror movement enough to cause focus length to change. Most mirror mounts are required to be 'loose' enough to not allow any stress points on the mirror as temperature changes, however not so loose as to flop around.

Hot glue is a one method that will allow a stress free attachment of a mirror to it's holder.

Lefty


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