I have a bunch of random sized empty soul gems in my inventory ranging from petty to grand (not black or azura though). I'm casting soul trap on bad guys, just some run of the mill npc mages (nothing special). I have 60 seconds to kill them for the gem to fill with their soul. I kill them in less than 10-15 seconds, I have been seeing nothing happen lately, or it tells me that I don't have a soul gem large enough.

Could someone list the soul sizes that fit according to the creature/person killed? I'm guessing that a Skeever or a spider would be a petty soul gem and a undead lord or tough enemy would be a grand gem? But more importantly I would like to know why I'm not able to fill my empty gems with regular "badguy" npc souls? Is a bandit/mage/necromancer soul bigger than a grand soul gem??

Thank you.

You need black soul gems to capture NPC souls. Hunt giants and mammoths for grand souls. Also NPC souls are grand, but you just need a black soul or the black star to capture them.

black soul gems for humans. The black star is your best bet since black gems are exspensive.

Any humanoid npc is black soul gem level only. For enchantment purposes its equal to a grand soul gem. Idea being black soul gems cost more to buy and are rarer, yet your able to fill it easily. Grand soul gems are fairly common, yet killing a creature that will fill it to capacity is annoying. If I recall right a drauger lord would be considered a grand soul.

Thanks guys.

Enchant something with one second soul trap and it will trap during the last blow, much higher charge usage. Bow is good for faster moving things.

V
There's even more lore in Dark and Demon Souls.

The lore of black and white in case you wonder

http://www.uesp.net/wiki/Lore:Souls,_Black_and_White

question about black star and enchanting. how does it work? I heard that it's re-usable.

I have a question I've been wanting ask abou this topic....

If I have bunch of different unfilled soul gems in my inventory, how does filling it work?

If I kill somethin small will it fill the soul gem according to that soul....or will it fill another one?

What happens if I use up all the small gems and I kill something small......will it fill a larger gem?

I can't remember what happened as it's been a long time since I played Oblivion.

When a soul gem being used to fill up enchanting or enchant something, the soul gem will be destroy in the process of extracting soul of it. but Azura's star is an artifact from Azura herself, it will not be destroyed when when the soul extracted. so it become reusable

http://www.uesp.net/wiki/Lore:Azura%27s_Star

http://www.uesp.net/wiki/Skyrim:Souls

The Black Star is refilled with human souls, while Azura's Star is refilled with white souls (killing a mammoth fills it completely, but anything else is too small). Azura's Star does not get consumed when enchanting items, but needs to be refilled after every use. It is a grand soul gem.

And, as far as filling soul gems, if you get the line "you do not have a soul gem large enough" it's because if you do no have either the Black Star or black soul gems, human souls are not going to be captured. Petty gems are filled with things like mudcrab souls and wolves, but if you also have other gems, like unfilled lesser or common gems, a mudcrab soul will sill be captured in them, but it will not fill it completely (almost like wasting the gem, but you can still enchant with it, it's just the same as a petty soul gem).

Petty: creature souls below level 4.
Lesser: creature soul below level 16.
Common: creature soul below level 28.
Greater: creature souls below level 38.
Grand: Can hold any creature soul.
Black: Can hold any human soul.

This also works when you would fill a lesser soul gem with a petty soul, it would say "Lesser Soul Gem (Petty)" which tells you it has a lesser soul than it would normally hold. I hope this helps you with soul gems.

It works just like it did in Oblivion: when you kill something, it's soul will go into the soul gem of the appropriate size. If one's not available, then it will move into the next largest available. For example, You kill a wolf; it has what would considered to be a petty amount of lifeforce (soul). If you use Soul Trap, it would move into a petty soul gem, if there's an empty one. If not, it will look for the next largest available size. If the only empty sould gem you have is a grand, then you would get a petty soul in a grand soul gem. This is not desirable; hence it's always a good idea to keep a good stock of empty lesser gems on hand.

You could also go the lazy route and give your follower all of your empty soul gems along with a soul-trapping enchanted weapon. Then collect filled soul gems periodically to recharge/enchant your weapons. That's what I do simply because I use a weapon with a different enchantment on it and I can use my favorite weapon while my follower collects souls for me at the same time.