Greater Arcane sight rules Question

[Khelvan]

If have two question about that spell since its now heavily used in my campaign.
First it lets the user know what spells are on effect on something he / she sees.
What is with magic items the target wears. There auras are visible too.
Can the user use GAS to determine what this items are?

Second.
The spell says that the caster concentrates on a target he can determine what if and what caster level the target has.

How long does one need to concentrate?
And what can the person that does the concentrating do ( which Action are allowed ) do in that time?

Any advice welcome.

regards.

Khel.

[Gauss]

First, no you cannot identify magic items worn on another creature via either Arcane Sight or Greater Arcane Sight because neither spell provides an exception to the 3 round clause nor the 'thoroughly examine the object' (usually considered to be handling the item) clause.

CRB p106 wrote:

Attempting to ascertain the properties of a magic item takes 3 rounds per item to be identified and you must be able to thoroughly examine the object.

Note: Some GMs may waive the 3 round clause because Arcane Sight gets three rounds of Detect Magic information in 1 round.

Second, it is a standard action to concentrate on a target.

CRB p244 wrote:

If you concentrate on a specific creature within 120 feet of you as a standard action, you can determine whether it has any spellcasting or spell-like abilities, whether these are arcane or divine (spell-like abilities register as arcane), and the strength of the most powerful spell or spell-like ability the creature currently has available for use.

[Abraham spalding]

The caster could make some guesses as to what the item is or does based on the aura. That does not mean he will know just from looking.

For greater it depends on how "magical effects" is defined. I would generally think that would include what effects magic items are having on the character.