I'm a lens snob, so when I tried the Tamron 15-30mm f/2.8 for the first time, I was skeptical. It's quite inexpensive compared to the Canon lens, but I'm very pleased to say that I'm really really happy with this lens. Right now it's my workhorse. Most landscape photographers don't shoot long lenses, but Michael Frye encouraged me to try long lens landscapes and it's been very helpful, so I included a 70-200 on the list as well.
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