If you are using a pair of Fatshark Dominator (any model, V1, V2, V3, HD, HD V2) and the color appears to be washed out when using a TBS Dominator Rx (5G8) this means you are probably using an older version module which were shipped before November 2015. The problem with Fatshark Dominator goggles is that they are not using video signal normalization on the input. The good news is, there is an easy fix.
All units shipped from our facility after the 1st November 2015 will have this issue fixed. If you happen to have an older module you may choose to repair it using a pair of tweezers, soldering iron and a 10 Ohm resistor. It is all you need to DIY this fix.