When I create a mosaic it says 35 Degrees East. Does that mean to rotate my camera 35 degrees? Also, when I add panels to the mosaic how do I get back to the original view with the panels lined up correctly?
Hi Dennis, welcome to the forum!
You have two different places where position angle matters. One is inside the camera section of the Telescope Simulator. In there you can rotate your entire framing regardless of mosaic settings - 1, 4, or 100 panes. This is the general rotation of your whole framing. In the following example, the position angle (rotation) is set to 0 degrees, which means the top of the whole framing points to the North Celestial Pole.
Once inside the Mosaic settings things can get a bit more complicated depending on the declination you are shooting. As you move towards the celestial poles, you’ll notice that if you don’t rotate each one of the mosaic panes they will not be aligned between each other. Take a look at the following example:
In this case I’ve set up a 2x2 mosaic centered on the North Celestial Pole. The pole is exactly where the crosshairs is, at the center of the screen. If we image each pane having North up, you would end up with the mess shown above. Note how the “top” of each frame, one of the long sides, is pointing towards the celestial pole.
Since this is probably not what you’d expect when imaging extreme declinations, you have the possibility of rotating each one of the panes to have a perfectly aligned mosaic. In order to do that, you need to enable the option “Rotate panes to preserve alignment”:
Note how the mosaic has all its panes perfectly aligned now. But in order to capture this you’ll need to rotate your camera differently for each one of the panes. As you can see in the list, each pane must be rotated quite a bit for extreme declinations! This is usually not a big problem for declinations between -70 and 70, where panes are off by at most ~3 degrees, but as you move closer to the celestial poles you’ll probably want to make sure this option is enabled.
Hope this helps! 
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