This is amazing! I don't really know much about eyepiece projection. Isn't that basically where you use the camera and a T adapter to view through the telescope's eyepiece?
Edit... I also wonder how well collimated I need to be. I've been fiddling with that for a while, trying to get it right, and I've run into a few small snags. One of which is that when I get perfectly concentric rings on an inward defocus, the outward defocus shows a slight irregularity. If I try to adjust for the outward defocus, the inward is then out.
Yep, eyepiece projection is pretty basic:
In 2017 I experimented with Plössls and a fancy projection adapter; for the 2018 planetary season I upgraded the eyepieces and downgraded the adapter. The extendable adapter had some major problems—it turns out there's a distance limit between the eyepiece and the sensor above which you get strange ghost artifacts that degrade the image quality. And it was at the absolute limit in its most compact configuration. So my current adapter's design is simply a T-thread extension tube with an interior ridge and a side screw to hold the eyepiece in place.
Orthoscopics eyepieces with a narrow FOV (Abbes in particular) produce the sharpest, highest contrast images of any eyepiece design. With projection through the Skywatcher 180, a 12.5mm works perfectly for Jupiter and fairly well for Mars near opposition (though I used a 9mm on Mars later in the season to get more pixels across the disk). The 18mm worked better for Saturn because of its dimness; I then used 2x output size from the stacker.
As for collimation, I simply used the Skywatcher as shipped; I've only recently delved into trying to collimate it. I have not noticed the hysteresis you mention.
Edited by BQ Octantis, 01 May 2019 - 03:42 AM.