The video by Petzl that demonstrates proper ice screw placement technique, as well as how to set an anchor and a v-thread in waterfall ice. It's clear seven minutes don't suffice to cover all ice ...

Ice climbing belays: 1. The ice screws should be positioned almost vertically one above the other, and no closer than 30cm, so as to create an acute angle. Place screw gate carabiners into the ice ...