DTV and HDTV - poor color

I have an OTA to receive local channels in HD and then use a Winegard HD Receiver #RC-1010 ( all becasue Direct TV does not offer local channels in HD in my area, yet). My problem is that the color on my reception is not good, the greens and reds do not come in as they should. I have tried adjusting the TV but to no affect. Any ideas on what I can do would be appreciated.