Raven Guard shoulderpad trim

[Paulo187]

I'm currently painting up a Raven Guard 3rd Company force. I've seen many examples of Raven Guard with the trim of both shoulder pads painted red and a few more with just the right shoulder pad trim in red (leaving the left pad completely black).

Which is the correct way? I'm painting Tactical Marines and Assault Marines. Should they be different? Any help would be appreciated.

P.S. Sometimes I see both arms painted white as well as the helmets. What does this even mean?

[gresha]

"The right shoulder guard trim denotes the type of Space Marine. Green is for tactical squads, red is for assault squads and yellow is for devastators. The left kneepad displays the company number"

Source - http://wh40k.lexicanum.com/wiki/Raven_Guard#Culture_and_combat_doctrine

Most of the time i see them the right shoulder trim is colors and the left is black or white.

[Megad00mer]

"The right shoulder guard trim denotes the type of Space Marine. Green is for tactical squads, red is for assault squads and yellow is for devastators. The left kneepad displays the company number"

Source - http://wh40k.lexicanum.com/wiki/Raven_Guard#Culture_and_combat_doctrine

Most of the time i see them the right shoulder trim is colors and the left is black or white.

This appears to have changed in the new Space Marine codex. Now the trim denotes company based on the Codex Astartes. Yellow/Gold for 2nd company, red for 3rd, green for 4th etc. So if you wanted a truly accurate 3rd company scheme based on latest fluff, go with a red trim on the right shoulder guard. White helmets are worn by sergeants while both white arms and helmets denotes veteran status.