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Message: <blockquote data-quote="Binastro" data-source="post: 3181283" data-attributes="member: 111403">. Hi David,. Thanks for trying.Three neutral density filters would give 1.55% transmission i.e. 1/64.The problem is that when you reduce the brightness of Venus as viewed by the eye, you are also reducing the brightness as seen by the instrument.In other words, does a very bright object form a larger visible image than a fainter object?As to my own eyes, when I look at the bright moon I see a much fainter ghost image in the double glazing. This secondary image is for me much nicer. It is smaller and I see more detail in the secondary image because it is not bright.I know that many binoculars produce large star images even from average brightness stars, I think that is because of the optical design.</blockquote>