JC a dew shield that is 1 1/2 longer than the objective's diameter will be as efficiant as it can possibly be , eg . 150mm long for your lense set , good luck and please keep us all informed as to your progress.
Just draw the light cone out full size to get all relivent dimentions .
Brian.
Quote:
Originally Posted by Shiraz
or just put up with a bit of vignetting. The other thing to consider is that anything you put within the input light cone can scatter light into your optics, so if the shield does encroach into your field of view, make it black.
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