SoC -> CS : Massive FPS Drop

[Solarian]

I have recently finished SoC, and started CS.
I played SoC at 1280x1024 and medium settings (with view distance turned up all the way), and I currently also have CS at medium settings (with view distance at the default medium setting),
There is an incredibly-noticeable drop in both FPS and graphical quality - not only does CS play far worse than SoC, it looks far worse.

Are this any particular reasons for this? Or is CS just for some reason far more poorly-optimized than SoC?

[faemir]

Turn god-rays down to low, and you should go massively up. case-in-point I go from 15fps to 60+ and they don't really look worse at all.

Also, directx9 mode runs much better too.

Anything more I can't say, but putting godrays down fixed it for me, though i'm using the CS Complete mod which does change textures and skies and stuff...