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Re: ND1000 filter - a data point
From: Tony Oz
Date: 2022 Oct 28, 10:27 -0700
From: Tony Oz
Date: 2022 Oct 28, 10:27 -0700
Dear Noell,
By my experience with camera filters as shades for a sextant - camera filters are NOT good at that.
Yes, they are optically flat but they are not parallel, there is a rather significant amount of wegness in them. I noticed that sad fact when installed a polariser as a horison shade. Depending on the orientation (that polariser filter can rotate in its' bracket) the IE wandered as much as ~three arcminutes.
You will have to account for possible wedgeness in such a DIY shade.
Warm regards,
Tony
60°N 30°E
