Our route on LAN was San Francisco to Miami to Santiago to Calama. We arrived at Calama around 5 pm where we shared a cab into town with Veronica and Wilson, a Brazilian couple we met at the airport. From town, we caught the 6 pm Frontera bus to San Pedro where we stayed at Katarpe (which we liked) for the next three nights. On our return to Calama, we took the Tur bus back, which was the same cost but quite a bit more comfortable. Serene and I got along very well with Veronica and Wilson and we collectively reserved tours for the next two days to the Salar de Atacama, Valle de Luna, and Tatio geysers. Ray joined us in San Pedro for the Bolivian Altiplano trip a few days later; we later found out that the airport transfer from Calama to San Pedro for 7000 pesos is a roundtrip fare, which is about the same price for a single traveller taking a cab into Calama followed by a bus to San Pedro.
We spent our first day in the San Pedro area visiting Laguna Chaxa in the Salar de Atacama (contains 40% of the world's lithium reserves) and two altiplano lakes, Laguna Miscanti and Miniques. At the time, we thought these sights were really spectacular, but after visiting the Salar de Uyuni and the altiplano lakes in Bolivia, these sights paled in comparison. On the other hand, we could get relatively close to flamingos in Laguna Chaxa, which we couldn't in Bolivia, and Laguna Miscanti is the deepest shade of blue I've seen in a lake (even compared to Crater Lake), especially when contrasted against the arid dry desert landscape.
We got up at 4 am the second day to catch sunrise at the El Tatio Geysers. The five hour time difference between the US west coast and Chile was enough to throw our sleep cycle completely off on the second day. 4 am Chilean time is 11 pm Pacific time, which is just about the time we normally go to bed. Needless to say, we didn't get much sleep that night and we were constantly nodding off throughout the day. The Tatio geysers are at 13543 feet and watching the steaming vents at sunrise was worth the trip. The second half of the day was to Valle de Muerte and Valle de Luna. The former had some unearthly scenery but the latter was a little disappointing, although it was quite nice walking along the top of a sand dune with the warm colours of the setting sun lighting up the sand.