Skiing in Rocky Point in the Alta Periphery, myself and two other skiers. Our objective was to ski some fresh snow, and jump off some of the cliffs that Rocky Point offers. After a lap skiers right of the main cliff area, we skied through the skier's left cliff area. An initial ski cut, and run, produced no sluffing or snow movement. On our third run, I skied below and slightly off to the side of a cliff to shoot a photo of one of my partners jumping off of said cliff. None of us were expecting any snow movement in this particular area, as we had been ski cutting and skiing steeper slopes without any results. The slope we were on was not particularly steep, I would estimate it at 23 degrees, with a slightly steeper bit just below the cliff. My partner took to the air, and landed right at the bottom of the cliff in a pile of what must have been wind deposited snow, with a dusting of new snow on top. His impact broke through the slab 8'' down at the impact point, it propagated 15' on either side of him, with the crown tapering down to only an inch or two at the edges of it. I saw the slab break, and move toward me. I didn't have any time to get out of the way. The snow was moving slowly and shallowly. I stayed on my feet the entire time as it pushed me 150' or so down the slope. It was not deep enough to bury a person, and the moving debris only came up to the back of my knees at the deepest point. The slide itself was not particularly scary for these reasons. It was shallow, slow moving, and in inconsequential terrain. However, it still left me feeling shaken. We had been safe up until this point, and I got complacent with the conditions. The information that we had gathered up until then were positive indicators that we were making good decisions, and we let our guard down. None of us expected to set off a slide where we were, based on what we saw, and overlooked the fact that if something were to slide, it would be in the exact spot that it did. North aspect, wind loaded, at a rocky spot to release, and with a large trigger mechanism. In this case, a skier landing on the slope. It will absolutely make me think much longer and harder about choosing to take photographs of skiing from an on slope position.