I have the first generation 10-24mm and love it for landscapes. Its on my camera for 95% of the time as I love wide angle landscape photos. Its also been to New Zealand with me. PM me if you want any tips on cool photo locations.
I use a Samyang 12mm F2 for wide angle astro stuff, but have also taken this on general landscape trips if I want to save weight. its tiny. Optically is good, but probably not quite as good as the 10-24. Manual Focus only.
There are a few photos I took the other day on the 10-24 in the landscape photo page.
An early start (04:30) and a very hard slog in the ice up Red Screes was rewarded with some beautiful light on sunrise. Absolutely baltic on the tops. Timed the return just right as upon getting to the car the weather turned very quickly into dark grey snowstorms, and stayed like that all day...
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