Maintaining an illusion..

[Kerilstrasz]

A wizzard cast a silent image ...

Illusion (Figment)
Level: Brd 1, Sor/Wiz 1
Components: V, S, F
Casting Time: 1 standard action
Range: Long (400 ft. + 40 ft./level)
Effect: Visual figment that cannot
extend beyond four 10-ft. cubes + one
10-ft. cube/level (S)
Duration: Concentration
Saving Throw: Will disbelief (if interacted
with)
Spell Resistance: No

what that exactly means??
from my point of view, it stays in place as long the caster keeps in mind on it, thus , cast NO other spell for the duration, NOT taking dmg or any other effect that can break his concetration...but if he is not threatened... for example he stands on a balcony unnoticed (or invisible) he can extend the duration to his like without need to do anything else...
from my current DM's point of view whatever the situation the caster Has to roll a concetration DC 15 each round to maintain it....

which is true?????
plz provide me each and any reference to DMG and PhB books you can think of(Book and Pg plz)...

and secondary...
does the caster need to have eye contact with the place the illusion is created or he just need to know the place by any means just so he dont accidentally make a chair for example that hovers 1 inch from ground instead of touchin it?

BTW we are in a 3,5E
thnx a lot

[Ernir]

A spellcaster must spend a standard action each round to maintain a spell with a duration of "concentration". He is not required to make a Concentration skill check. See spell durations (http://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#duration).

The caster is not strictly required to have Line of Sight to the place where a spell effect is supposed to originate (although you must be able to see or touch the recipient of a targeted spell), although you must have Line of Effect. See aiming a spell (http://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#aimingASpell).
Whether you're able to correctly position an illusion with respect to the ground and such without seeing is a question best answered by your DM, I think.

[Malachei]

The Swift Concentration skill trick from Complete Scoundrel helps.

[Kerilstrasz]

well... we come to the point that my DM said... yes.. it doesnt say you dont have roll... it sais you have to concetrate.. so this is translated as concetrate roll... is there a page in phb or dmg that states i dont have to roll????

and unfortunatelly this is a core campaign and i cant use C.S. for that skill trick...

[VGLordR2]

Check
You must make a Concentration check whenever you might potentially be distracted (by taking damage, by harsh weather, and so on) while engaged in some action that requires your full attention. Such actions include casting a spell, manifesting a power, concentrating on an active spell or power, directing a spell or power, using a spell-like or psi-like ability, or using a skill that would provoke an attack of opportunity. In general, if an action wouldn’t normally provoke an attack of opportunity, you need not make a Concentration check to avoid being distracted.


Concentration
The spell lasts as long as you concentrate on it. Concentrating to maintain a spell is a standard action that does not provoke attacks of opportunity. Anything that could break your concentration when casting a spell can also break your concentration while you’re maintaining one, causing the spell to end.
You can’t cast a spell while concentrating on another one. Sometimes a spell lasts for a short time after you cease concentrating.


Emphasis mine.

[Krosta]

As VGLord correctly quoted, you should roll a Concentration check only if something distracts you while mantaining the spell active. Mantaining the spell itself is a standard action every round that requires no roll of any kind.