Spellcasting Items, Feats, Enhancements, Etc.

[Endarire]

Greetings, all!

Let's assume I use a spell from an item (a consumable, a clicky, or otherwise). What enhancements, bonuses from feats (like Spell Focus), and so on apply to this casting?

[Lonnbeimnech]

www.ddowiki.com/page/Artificer_Knowledge

and artificer Arcanotechnician capstone

Arcane Empowerment: The patterns of the most complex magical formulae are like children's drawings to you. You gain +2 Intelligence and +5 Spellcraft. You treat any non-scroll activated equipped item that casts spells (such as wands, rods, armor, or other activated items) as if they were staves, increasing their caster level to equal yours as well as increasing Save DCs to (10 + your Intelligence bonus + level of spell) if it would be an improvement. These increases are applied after Artificer Knowledge, so do not stack.

Sorcs don't get anything to improve clickies.

[Endarire]

If I cast a spell from a staff, do I use my save DC? My caster level seems to be affected.

Additionally, do metamagic feats apply to spells cast from items? What about racials and enhancements?