I have been trying to get shaders to work with these mods for a while and I've googled, I think everything that can be googled about it but I'm not getting it to work.
I was able to get it to work when manually modding the game. I was running a 1.8 server and had SEUS shaders working with no problems.
With FTB, I have tried every possible combination of ShadersMod versions recommended by people online and Optifine, which does the opposite of helping anything. If ShadersMod is active, the game will go through the lengthy loading screen but crash without an error message before the game is supposed to actually load (just goes back to the FTB launcher, and the log says no error code was recorded). It'll run with optifine, just half the frame rate.
Both of these jive with what I've read online. People have been using both of those mods with FTB infinity, or at least with earlier versions of infinity. Any ideas? Unfortuntately, I'm at work, so I can't get anyone a log file at the moment, but I can later if it'll help.