In order to photograph the firefall, the key is position, so plan to get to your location as early as 2:30 p.m. before the crowds gather. Bring an insulated pad or folding camping chair because you will be waiting a while.
If you are coming at a different time of the year and just want to photograph the waterfall, you have more flexibility. Spend some time scouting in the two areas on the map and look for the clearest views. With any luck, you will have first rights to any spot you desire!
As with most locations in Yosemite, Horsetail Fall can be photographed with a variety of lenses. If you are going after the firefall, using a tripod is necessary because the event takes place as the sun is setting and your exposures will be getting longer. Remember, you will be carrying your gear through snow, so proper snow gear and a good camera bag that will not throw you off balance is important.
You can use a variety of lenses to photograph Horsetail Fall depending on your location.
At this location, you are closer to the fall and are looking over the treetops. Longer lenses in the 100-400mm range work best. You cannot get the whole falls in from this location, so you will be zooming in to get the waterfall as it leaps over the cliff face.
From the river you can use a whole array of lenses going from wide-angle to telephoto. ...