Can anyone help with the quality of my youtube videos

I am having problems with youtube I film a video in 1600 x 900 with Dxtory and the Lagarith Lossless Codec and
Render with Sony Vegas Pro 12 I watch the video before I render and it looks great then I render and it
looks great but then I upload it to youtube and the quality is horrible here are the settings i use to film and render


http://xzombiebunnyx.imgur.com/all/



Here are pc specs if that helps at all


Cpu: AMD FX-6300
GPU: Sapphire Radeon R9-270x Dual-X OC & Boost
RAM: G.Skill Ripjaws X 4gb 1866mhz
OS: Windows 8.1 64 bit