Ken
I should have phrased that better.
“When the scope rotated the new camera position resulted in the front cage center of gravity to be in a different position and whilst the balanced back half did its serrurier stuff and sagged straight down the unbalanced front sagged at a different angle and collimation was lost”.
I could be wrong here as I've been up the creek without a paddle before but I'm reasonably sure of the logic.
Cheers
Stephen
Quote:
Originally Posted by Merlin66
Stephen,
Your comment:
When the scope rotated the camera changed position relative to the center of mass of the front cage and the front half of the truss moved in a slightly different direction to the back half hence loss of collimation.
This is what the Serrurier truss is all about.
The mirror cell, centre section and top ring must be rigid enough that there is no distortion or deflection.
The stiffness of the front trusses have to be matched against the back mirror cell trusses.
IMHO the problem comes down to the choice of material, section sizes and deflection calculations. Not additional weight or mass.
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