I bought a sennheiser 122 and want to get mounted EX1.someone can help me with some setting for camera and mixer. Thanks

You won't need a mixer with just the one mic, unless you want to eq on location.

No special settings on camera that I can think of. It's all pretty straight forward. Once you test it, if you have further questions, then re-post and I'll try and answer.

Good luck . . .