What lenses will work best for desert landscapes?

Question

I'm going to be travelling to the Middle East soon and was wondering what the best setup for photographing desert landscapes would be. Here's what I have:

Canon 7D

EF 50mm f/1.8 II

EF-S 18-135mm f/3.5-5.6 IS

It turns out the above lenses are not weather-sealed. I can probably go to a lens rental service. In this case, what are some good Canon (or any EF-mount) lenses that are weather-sealed and good for desert photography?

UV Filter

Tripod

Also, does anyone have any general guidelines/tips for photographing in the desert?

Answer

Those lenses will die in seconds in the desert if there is wind. Actually I saw another non-weathesealed Canon lens stop working in less than 10s while in the Peru desert. In Egypt we had more luck but still a lot of people in the group had sand infiltrate their lenses. This is a good time to use a Clear or UV filter too as even a weather-sealed lenses get scratched, the filter will be ruined after that. I had an expensive polarizer damaged on the first sand-dune, luckily nothing happened to the weather-sealed lens I had.

Fortunately you have a weather-sealed camera and you shout match it with weather-sealed lenses. There are plenty for Canon mount. Normally for landscapes people go with something on the wide side but a medium telephoto is good to compress perspective which renders desert photos more interesting. The 17-40mm F/4 or 24-105mm would both make great choices. On the 7D the 24-105mm does not give you wide-angle, so you probably want a wider lens for monuments and such.

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