Not to complain, but there are many cases where I feel we should all refrain from picking mushrooms. I do understand they are the fruiting body of a fungus, and they are open for several days to disperse spores. There are other concerns, however.
First, on a public trail, land, or open space, you are actually not allowed legally to pick anything nor take anything. Furthermore, many people would like to see the mushrooms growing and decomposing naturally, and as is, not picked and turned upside down. To do this in a public space is illegal and selfish to all other people trying to enjoy a natural area in its natural state. I dislike greatly when I hike a public trail and someone selfishly picked the mushrooms.
Picking anything in National Forest is illegal without a permit, and in a designated Wilderness it is especially bad. Picking mushrooms on private property is also illegal unless you have permission.
Use a small mirror to photograph them!