I bought a Planet-Waves optical tuner. It shines a strobe light on your string while you're tuning.
It works great with my steel-string guitar. Positive #1: There is no problem with jumping needles. Positive #2: There is no problem with competing sympathetic vibration. Positive #3: The is no problem with background noise from the room. Positive #4: The feedback is instant. Positive #5: It's small (size of a guitar pick). Positive #6: The accuracy is so good that the main limitation is how smoothly the tuning mechanism works. Positive #7: There is no problem with the tuner selecting E when you're tuning an A string. Positive #8: If you're inventive and knowledgeable, you can check your overtones and detect false strings. Positive #9: It's cheap. Unfortunately, it has only the six guitar notes EADGBE, so it's limited in usefulness for a 440 lute, and even more so for a 415 lute. An industrial strobe light (eg, ESL-100) would probably work, but it would be bulky and costs around $650. Yes, I know you're suppose to learn to tune by ear. To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html
