If a mage casts a barrier bubble centered on himself would it totally surround him or would it only cover his forward vision arc??

Only where he can see, which is about 120 degrees if you count the peripheral areas.

Really? I thought the mage just had to be able to see the center of the barrier (himself, which is a given) and the barrier creates a dome all around him.
I don't have my book, but is there an explicit quote one way or the other, or are we both assuming/interpreting differently?

I don't have the book either, but spell effects don't extend out of your line of sight unless specified otherwise. It's possible that the barrier spell says it works where you can't see it, but I don't remember that being a clause.

No it doesnt mention the ability to go out of sight specifically. Just says it can be a wall or dome and increase or decrease in size like normal radius spells.

Note that if the mage lies down then he can quite possibly see a larger arc, but that may cause other problems.

He'll see the same 120 degree arc, it'll just have a different orientation. If he looks straight up while doing it he'll probably end up leaveing plenty of room all around for people to enter between the barrier and the floor. That might cause them to squeeze through a few at a time though, enabling a conga line of death if they're lemmings.

I believe the spell says it will create a wall or dome at or around it's target. Since a mage can always target himself you should be able to create a dome around yourself.

Also, barrier is a manipulation spell, and manipulation spells have always been able to create effects outside of the magicians line of sight, ie fireball at a hallway intersection... goons hiding around the corner get fried.

Not all manipulation spells have been able to.

True, he will see exactly the same area, but he can optimise his coverage by trying to avoid looking at areas where the ground prevents him from forming a barrier.

The mage could also use some optics which allow him to see a 360-degree field including the ground on all sides. I'm sure we've all seen pictures using ridiculously wide-angle lenses, particularly the ones with the sky in the middle and some famous building about the edges. I'm having a bit of troubble finding one with google, but I'm talking about something like this.

The good thing is that once the spell has been cast, the magician does not need to see it in-order to sustain it. He thus only needs to look through his fish-eye periscope as he casts the barrier spell and not afterwards.

The problem seems trivial to me. If you disagree that a mage can't make a full bubble if he can't see all of where the bubble will be, just make him look all around during casting. Once a spell is in place, it doesn't have to remain in line of sight to be sustained.

It comes down to how long you think the "line of sight" requirement allows. Some (like myself) feel that it's an instantaneous requirement. At the exact moment that you choose your target or area, you check line of sight. Others feel that it's checked throughoutthe entire casting of the spell, and so you can look around, ignore visual arc problems, and in general hit everyone around. The rules don't really speak to either stance, so whichever you prefer works fine. the second one makes mages more powerful, but not drastically so.

Should i specialize in gymnastics for all the spinning i will be doing ? hehe. Joking.

So you have to spin around like a magical girl when you cast area spells around yourself?
We need a FAQ so very, very badly.

What's your definition of LOS?

I usually use a very loose one where it covers the area the Mage could see if they happened to look that way. So for a barrier they can certainly do a dome since if they turned their head around they can see where the spell would take effect. This relieves me as a GM from thinking about checking if the character is actually looking at the exact spot they need to be looking at. Something that makes sustaining an invisibility spell on various different members of your team almost impossible if you interpet this any other way, since I certainly won't argue that I can keep an eye on two different people at once without some very peculiar eyes.

lmao your signature is pretty funny Apathy. Hehe i dont really consider a thread a discussion UNTIL the name calling and flame baiting start hehe.

My view on it would be that it refers to the target being in LOS not the effect, if you want to argue that you can't see behind yourself then be sure to note that you generally can't see through the target and as such will be leaving a "target" shaped hole on the side opposite yourself.

Thats just my 2 creds though.

Hey thats some damn good common sense.