Eclipse photography can call for specialized equipment, both for the hours of partial coverage before and after, and for the few short minutes of totality. A Poor Man’s Pinhole Mirror can avoid some of those equipment issues, and allow for relatively safe viewing. I do not know all the safe limits for Eclipse watching (except of course the use of ISO rated Eclipse Viewing Glasses) apart from my Darwinian sense which says “DO NOT LOOK AT VERY BRIGHT IMAGES”.
Continue reading Big Picture Pinhole Mirror Solar Eclipse Viewing at 341 On The River.
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Dec 15, 2021.
Deep apologies to all. My original analysis of Nov 11 had many inaccuracies.
Thanks to Jeff Roberson who pointed out a reversed force vector in the Drive Train figure. I have hopefully corrected most of the errors in this version (V19). The propeller now rotates in the same direction as in the videos of Blackbird. I have also clarified the vector math conventions making them easier to follow.
Continue reading Improbable Wind (and Other) Propulsion Systems at 341 On The River.
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Look closely at the winged creatures around us and you’ll see many have extraordinarily athletic abilities, some of which we are trying very hard to copy with the latest mechanical drones. Did you see the amazing formation flying, amid the regular fireworks, of lights carried by perhaps more than a hundred drones at President-Elect Biden’s victory speech on Nov 7?
Last season’s Eagle nest, nearly ½ mile away to the North on Audubon Island, is gone.
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