Here's some of the photos I've taken. The times in brackets are when I reckon they're best for photos.
There's some other locations worth looking at that I've not been to, I'll dig out some stuff for those tomorrow if I get time.
Garsdale -
map
Looking south from the station (morning/no sun).
Looking north from the station (afternoon/evening)
Looking north from a hill just north of the station (morning/early afternoon) IIRC you go up the road next to the SB platform, over a wall and across a little stream. Don't be tempted to take the shortcut off the end of the platform.
Looking south from where the road goes under the railway north of the station (late afternoon)
Ais Gill -
map
Looking north near the waterfall (late morning/afternoon)
Looking north near the road bridge (late morning/afternoon)
Lazonby -
map (this is too far north for the Gypsum trains)
Just south of the village - a field next to the B6412 (afternoon)