Mesh Focusing Masks

FOCUSING A TELESCOPE can take a great deal of fine-tuning and finesse. It’s hard enough to focus a telescope or lens by eye, even though most eyes are somewhat forgiving. Once you’re within the range of a half-diopter or so, the eye’s internal process of focus accommodation automatically takes over, at least for young eyes. Of course, there are mechanical constraints that have nothing to do with the quality of the image viewed. For example, manually adjusting the focus knob makes the view jiggle around the field. An image that jumps and shakes instead of standing still is impossible to focus, no matter how you measure success. Motorised focusers mostly solve these mechanical constraints — judgment of focus becomes nearly real-time, if the focusing action is slow enough.

Most solutions for visual observing, however, do not cover the full scope of the focusing problem. Astro-cameras possess no biological eye accommodation, making them even more