I spent two weeks in December in Torres del Paine natural park. You should really go to see it. It is wonderful.
Some tips (that can be criticized since I have been only there one time).
- You are going there in peak season (summer time down there), so it is going to be expensive.
- If you rent a car in Punta Arenas or Puerto Natales to go to Torres del Paine, beware that the last Gas Station it is in Puerto Natales, from there there are no more Gas Stations (if memory does not fail me, from Puerto Natales to Torres del Paine, it is like three to four hours driving). They say that you can buy gas from the Hotels in Torres del Paine, we did not do that, so I don't know how difficult it is, or how expensive it is.
- The most economic place where to sleep is camping, but of course, you have to take your camping gear. You can sleep for free one night in "Lago Azul", but the installations are quite limited (no restaurant...), as I was saying, free camping. Lake Pehoe has "Camping Pehoe", they have some kinds of bungalogs, I don't know if they are ok or not, we took our own camping gear. I don't know for sure, but they told me hotels in the area are expensive, starting around 250-300 dollars per person per night... up to 3.000-4.000 dollars per person per night if you go to Explora hotel or Tierra Patagonia. You can eat in camping Pehoe for around 20 dollars each meal, but they have strick timetables, so, depending on the dates, dinners or breakfasts are not photographer friendly.
- To get inside the park you will need a permit, you have to pay for it, it was not much, I don't remember right now, maybe around 10-20 dollars? It gives you access to the park for 3 or 4 days. Anyway, at the sunset - sunrise hours, we never saw anybody there checking the cars going in or out.
- Wind, strong wind, take with you somekind of windstopper/goretex jacket... sturdy tripod.
So, the most famous landscape locations are Torres del Paine and Cuernos del Paine, from Lago Azul you have a nice view of Torres del Paine, I will also explore the road that takes you there, they have a really nice view. Explore lake Pehoe and Salto Grande and Chico area, you will have wonderfuls views of Cuernos del Paine. If you like photographing animals, you will see lot of Guanacos, Ñandús, Vultures... and of course the king there is the Puma, but it is difficult to see, the park ranger tolds us some areas to go to see them in the early morning, when they are out of their caves hunting, but we did not have the lenses to go to photograph them.
I love the park, and I will probably return in the next years to there... If you have the opportunity, don't miss it.