Yes, actually. The first time I used it on my f/5.6 Newtonian was with Rich Tenney at the Lakeside site some years ago. Even this method is not accurate enough for precision collimation with very fast optical systems. At f/4.5, collimation must be within a fraction of a milimeter. Even projecting a grid leaves too much room for subjective (or perceptive, really) interpretation. Repeating the procedure could probably average-out any residual errors. But even if it worked without a star-test tweak the first time, it still takes time that I don't want to spend at every set-up. It occured to me that one could possibly use a video feed at the eyepiece, and watch a screen while tweaking the collimation screws- if the camera were sensitive enough to detect the diffraction rings, which isn't likely. But here again, I don't want to HAVE to adjust collimation every time I set-up. I'll check it each time, but only want to adjust it if necessary. Assembling a telescope every time means at least a minor adjustment for precision collimation with a large reflector. At this point, there is probably no way to convince me of a necessity for a truss-tube design at this aperture. Thanks, Kurt. --- Canopus56 <canopus56@yahoo.com> wrote:
Are you familiar with holographic laser collimation?
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