![]() Last updated: 23 December 2004 |
Subject: Some Technical Tips: "Radioactive" focusing aid Sent: Wednesday, December 22, 2004 02:10:27 From: Mr. Tom (MrTomsMail@gmx.net) here is a picture for your Some Technical Tips area: "Radioactive" focusing aid This cardboard made focusing device for my Celestron 9 has 3 triangle shaped holes, pointing towards the SC middle axis. So all in all it looks a bit like a radioactivity sign. It has 3 advantages: - 3 wholes means more light than 1 or 2 holes - 3 objects are easier to overlay than 2 (and their dancing looks funny ...) - in focus you can even fine-focus because of the 6 spikes around a star, due to the triangle-shaped holesTry it yourself ! Cheers, Tom ![]()
Mike here: For more on the usefulness of the Hartmann Mask see the article '"Hartmann Mask" Focusing Aid'.
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