Has anyone ever built what I'll call a Newtonian camera? Since my first posting 5 days ago, I've read a lot and learned more about coma correctors and sizing of secondaries. Again, my desire is to cover my APS-C sensor with the 100% illumination zone while using a small secondary mirror.
The idea of a "Newtonian camera" came to mind. This "camera" would be the entire OTA, purely a camera or EAA scope, no visual use possible. I suspect this is done in large observatory instruments. I remember seeing pictures of observatory reflectors with all of the instruments located where the secondary mirror would be.
So the idea would be to eliminate the secondary mirror all together and replace it with an image sensor + coma corrector tube assembly, aligned on the axis of primary mirror. I'm thinking this tube assembly would take the shape of a cone, with the sensor near the tip of the cone, and the coma corrector optics located in the wide portion of the cone, where the primary mirror rays are entering. In theory the diameter of this sensor tube assembly could be very small, possibly smaller than the typical secondary mirror.
Anyway, not a simple DIY project for sure, but just wondered if such a "camera" had merits or had been built.
Edited by hukhound, 20 July 2019 - 12:57 PM.