p.2 #1 · 10-20mm vs 14-35 for landscape photography
IMO, a 14-35 is significantly more versatile for landscape use than a 10-20. First, while I love ultrawide, the 10-14mm range is really a specialized width that in my opinion has more uses for architecture than landscape. While I shoot ultra wide landscapes from time to time, it’s rare I need wider than 14mm, and most of the time I’m in the 16-30mm range when shooting wide. 10mm is really specialized because it exaggerates the foreground to an extreme degree and makes distant things appear very small in frame. For landscape use, the extra long end will save you a lot more time in lens changes than the wide end will be a savior in having the extra width.
Second, to use things like ND or polarizing filters with the 10-20 you will need an unwieldy 150mm filter holder, compared to standard screw in filters on the 14-35. While polarizers can be something to avoid when there is lots of sky on an ultra wide, I find them invaluable when shooting waterfalls and in gorges, where the ability to cut wet rock reflections is key.
If you still really want that extreme width capability from time to time, getting the 14-35 and then something like the Laowa 11mm f/4.5 for times you need the extra width might be a better option. Those two would be cheaper than the 10-20 as well.
p.2 #2 · 10-20mm vs 14-35 for landscape photography
When I took long road trips on my motorcycle I used to pack the 16-35mm f2.8 if I wanted a wide lens. i eventually gave that up in favor of the Sigma 12-24, f4. For my shooting it just worked out better.
