A few JPEG screen shots from my DSO-2090 USB Oscilliscope.
Just got it in early April and was looking at "waveform behavior" on a few LED strands that don't act the same (different manufacturer).
Half power (intensity) from an ACx8 into a string of incandescent mini lights.

The TRIACs are turning on half way through the input sine wave.
Full power (intensity) from an ACx8 into a string of incandescent mini lights.

Very clean waveform from the TRIACs