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I'm using a Lunt 2" Herschel wedge with an Explore Scientific ED102 triplet. The Lunt wedge has an ND3 filter permanently installed. Even when pointed at the sun all day, the wedge doesn't even get hot. Just a little bit warm. The result is just a tad bright, so I add either a polarizer filter or a Baader Continuum filter. Because of the way the wedge works, the polarizer can be rotated to adjust the brightness. I've been using a Lunt zoom eyepiece.
However, when I use this set up for public outreach, a certain percentage of the population doesn't show as much respect for my equipment as I'd like. They grab and yank. For that reason I've had to replace the stock focuser on the ED102 with a 3-inch Feather Touch. They can grab and yank that until the cows come home and it won't budge.
And no, you don't add any filter over the front of the OTA. All the light and heat goes straight through the OTA and into the wedge. 95.4% of that goes straight out the back of the wedge and into a ceramic heat sink. The rest is attenuated by the ND3 filter to a safe level.
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