Thread by @dean_frey

Crosby, Stills, Nash & Young by Tom Gundelfinger O'Neal, 1969, for their album Déja Vu
@Smithsonian National Portrait Gallery
Wait, you count six? Ahmet Ertegun convinced CS&N to add Neil Young, & on Déja Vu they added session musicians Greg Reeves & Dallas Woodrow Taylor Jr.

There's a different Tom Gundelfinger photo on the cover of Déja Vu, which had a very expensive design concept by Gary Burden. There was even a 4x5 tripod-mounted wooden tintype camera at the session, but this was apparently taken with a 35mm camera.
Not sure whose dog that is.

Joni Mitchell by Tom Gundelfinger O'Neal, 1968

Tom Gundelfinger O'Neal
Neil Young in Peter Tork's pool, between rehearsals

Tom Gundelfinger O'Neal
Jimi Hendrix before burning his guitar onstage at Monterey International Pop Music Festival, 1967
"The stage was 7 feet high. I’m a little over 6 feet. It was awkward to shoot from below the stage because it was hard to see over it."

Jim Croce by Tom Gundelfinger O'Neal
"We were shooting on the streets of Venice, California, and this little dog came up to Jim and hung out with us."

Tom Gundelfinger O’Neal with a print of Joni Mitchell
He counts Richard Avedon, Edward Weston & Annie Leibovitz as influences.

A great Tom Gundelfinger O’Neal cover photo for B. B. King's 1972 album Guess Who

Tom Gundelfinger O’Neal's cover for John Phillips's 1970 solo album, with a couple of other shots from the photo session