New head lamp's power

I woke up early in the morning and started to climb about 5:30 AM. One of the object of the climbing was check the performance of new head lamp.
As a result, the 350 lumen power was great. I could see around as if it was daytime. If I used 350 lumen power continuously, the battery would be wasted only for 2 hours. So, I selected the power to 100 lumen. It was enough power for walk in forest. I liked the new lamp.