Getting to the correct position in each meadow gives you the best views. Carrying the proper lenses and filters into the field will give you the best tools to make good images.
As with most locations in Yosemite Valley, Sentinel Rock can be photographed with a variety of lenses depending on your location and your desire to include the formation in the grand landscape. As always, a tripod, cable release, and bubble level can help you improve your images. Two filters are also useful for this subject.
Lenses for photographing Sentinel Rock range from wide-angle to telephoto, depending upon your shooting location.
From Cook's Meadow, you want to use wide-angle lenses so that you can include Sentinel Rock in context with the surrounding landscape. If you want to photograph the rock in the vertical orientation, it takes at least a 35mm lens to get it all in from top to bottom, and at least a 28mm lens if you are going to take a horizontal image. You can use a short telephoto lens if you want to fill the frame with just a portion of the rock face. If you are going to photograph the Sentinel Rock with the small rapids found under the footbridge, wide-angle lenses from 14-20mm are necessary.
In El Capitan Meadow, you can use a telephoto lens in the 100-400mm range to fill the frame with Sentinel Rock, or a wide-angle lens in the 24-50mm range to photograph the ...