Well done! I've tried this once myself and it took me too long to get the sun's position right for this effect. Too much tinkering for me
It's a pity that the left side of the image is all dark because of the casted shadow.
How does the planet look when you switch off cast shadows in the sunlight settings? Is the eclipse effect gone then or do you still have a glowing atmo of the planet and does it look very bright. If so, then you might try making the planet very dark or something. Don't know if this works, just thinking. Never tried this before this way.
Martin
