why all the apratars are in square shape can't they shaped in spherical or any one else?
why all the apratars are in square shape can't they shaped in spherical or any one else?

In viewing through a magnifying glass, one usually positions one's eyes very close to the lens. Does angular magnification change if the eye is moved back?
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Last Activity: 3 Years ago

Last Activity: 3 Years ago

Last Activity: 3 Years ago

Last Activity: 3 Years ago