Invasion and Summoning Level difference

SO could anyone explain them to me? All I can find on google seems to be different theories and rumors :roll:

Im mostly intrested in how the red eye orb, red summoning sign, dragon eye, GL sign and Blade of DM eye/ring works!
In the burg I have been invaded by red phantoms who are under lv 10 (me 76) and sometimes I have invaded way lower player than me with th ered eye orb. I havent tried Blade of DM yet
AND how do I know the players level I killed by the souls he gives me? isnt it something like this: I am host: souls I get are 50% of what enemy needs to lv up. I invade: I get 10% of the souls my target needs to lv up. :bom:

Im gonna check tomorrow if anyone has posted something!

Yes, that is how you figure out levels....

....and I have never heard of anyone invading far below their level with the red eye orb.

I don't know the specifics, but until someone comes along with a better answer I'll provide what I know:

Summoning (white, red, gold signs): Host level +-(10 + 15%)

Red eye: I think it's -10 to infinity. With the red eye, there is no upper cap. You can invade a SL712 as SL1. Not sure what the lower limit is, though. So, if you're the host, and you get invaded by a Red, he can be any level below yours.

Blue eye: Probably supposed to be the same as summoning, but has been known to invade down. Not sure if it's supposed to invade down, or what the real lower limit is, but I have been invaded by Darkmoons more than twice my level. As a DM, it's probably pretty rare that you invade down, but there are enough of them that, as a host, you shouldn't be surprised if you're invaded by much higher level DMs. So don't go joining DMs expecting to invade people half your level non-stop! But it might happen once in a while.

I'm not sure about the Dragon Eye or the Gravelord covenant, though. They're probably the same as summoning, but I don't know.