Skyrim- On Enchanting Effectively (Part Six)
There are naturally a number of enemies that do not possess souls, such as the dwarven automata or the most common undead, but some of the other exceptions to Soul Trapping you can find are a bit surprising as well. You cannot trap a Daedra soul in a gem, you can never trap the soul of something summoned even if it otherwise has a soul, and while you can ‘consume’ dragon souls after slaying them to learn more Thu’um, you cannot capture these souls in gems.
The use of black soul gems is the only way to trap a soul from a true humanoid, which strangely does not include the devolved Falmer. Black souls come only from the major races, which means that with the exception of bandits and certain quest events, you really don’t get a chance to pick up such souls. Of course, any character finding out that you use or seem to be seeking to use such souls for enchanting purposes will be put off at the least, with few exceptions.
Overall, practically speaking, enchanting is unlikely to be of too much use to you until you get it to a fairly high level or at least learn the Smithing perk that allows you to improve enchanted arms and armor. Because of the way smithing enhancements improve weapons and armor, often by ten or more points of damage or protection, the enchantments you can perform at a lower level of the skill are simply not worth being unable to refine your equipment as your smithing skill grows. Thankfully, it is quite easy to work on your smithing by churning out items which you can then enchant for your enchanting. As a general rule of thumb, save your Greater and Grand souls for use on your own gear at later levels, save half your Petty souls for recharging enchantments, and otherwise just steadily practice your enchanting skill. Most Dovahkiin find themselves fairly swimming in money at times, so consider these moments for your rare and expensive Enchanting purchases- soul gems both full and empty, and the occasional item from a blacksmith which bears an enchantment you simply cannot find in amongst your loot. In the end, this patience will pay off, when you are certain to have enough soul gems on hand to place the mightiest enchantments on your gear at a late level, instead of a random scattering of lesser souls to use.