A few weeks ago I saw advertised on Cloudy Nights an adapter that would allow me to attach my Feathertouch focuser to an Orion 120mm f/5 achromatic refractor. I didn't own one at the time, but it occurred to me that perhaps the WO 0.8x II reducer/flattener that I do own would work with this scope, which has a focal length of 600mm. An f/5 x 0.8 would yield an f/4, and a 120mm f/4 refractor sounds like a honey of an astrograph. It could only be used for narrowband imaging, but that's all I can do when the moon is full, and it's fascinating work, anyway. I made an offer to buy the adapter, then went looking for a used scope. I found one a few days later. With adapter and scope put together, I waited for a clear night. Here we are.This image is 18x420" through the Orion 120mm f/4 achromat astrograph, with WO 0.8x II reducer/flattener and an Astronomik 12nm Ha filter. The camera was the Atik 16. The image needs a bit more time. I hope to get that tonight, but this is a promising result for a used scope that, with adapter, cost less than $300.
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