I was talking to a friend at work today about rear cycle lights and we decided to take a couple of photos as a comparison, of I thought I would post them here just in case anyone should be interested. First the DiNotte 140L v a Smart 1/2 W LED 3 Function light (which is said to be visible from up to 800 metres, according to the sales blurb).
Rear light comparison 1
And one with the Cateye TL-LD600 turned on, as you can see from the flare these photos were taken on a bright sunny day.
Rear light comparison 2

Ps.
More more posts about cycle lights: