Yes, Rodrigo make their resolution (number of sprites) too big. To improve performance on the planets in the nebula (i.e. when you're moving too slow compared to nebula size), you can enable using skyboxes for nebula (set up TRMaxSkyBoxes 2 in main.cfg) - this is the same feature as used for the galaxy. The skybox textures takes 24 Mb of VRAM, so if you have only 512 Mb, don't use it. In the next version I will optimize this - to render nearest galaxy and nebula into a single skybox.
From what I've seen there isn't an objective "best" FOV to use- the view features the least "distortion" when the FOV is set to a value equivalent to the actual field of view the SpaceEngine window takes up. It isn't necessarily a problem that objects near the edge of the screen appear distorted on 60 degrees FOV because these are meant to be viewed on the edge of a 60 degree field of vision. If the window you are playing SE with takes up about 60 degrees of your field of view and you keep your eyes centered near the center of the window, the distortion near the edges of the screen will match perfectly what you eyes expect from objects at that angle in real life. This would create an optical illusion of a spherical field of view when in fact the screen is flat.
It is only if you do not have the FOV set to roughly the angular size the window takes up or you center your vision on edges of the screen that this distortion becomes a problem.
You may argue that we cannot be expected to keep our vision centered near the center of the screen (and I agree when this argument is applied to the GUI) but you can always rotate the field to center what is currently on the edge. In fact, this is how our eyes adjust to view different objects in real life- rather than moving around on our head they rotate to form a new center. It may take some getting used to, but in the end this method minimizes distortion while allowing for a natural curvature to the field of vision.
However, I do agree that a 40 degree default FOV setting would be better than the current 60 degrees, as most players will not be playing with a screen that takes up 60 degrees of their field of vision.
Edited by Gondor2222 - Saturday, 04.08.2012, 05:56