Ive been staring at reviews for weeks and honestly my head is spinning. Im taking a trip to Zion and Bryce Canyon next month and I still havent picked a wide angle for my R5.
Im torn between the RF 15-35mm f/2.8 and the 14-35mm f/4. The f/4 is cheaper and lighter for hiking, but I worry about blue hour shots where I might need that extra stop. Then theres the older EF 16-35mm III with an adapter but is it worth the extra bulk? My budget is capped at $2k and I just want to buy one and be done with it. Which one is best for those big canyon views?...
Man, I went through this exact same dilemma before my trip to Arches last year. I was honestly losing sleep over whether to get the f/2.8 or the f/4 for my R5. After hauling gear through the desert for a week, I can tell you I am beyond happy I went with the Canon RF 14-35mm f/4L IS USM. Hiking around Zion is no joke, especially if you're doing stuff like the Narrows or Angels Landing. Every ounce counts when you're climbing. I was worried about the blue hour stuff too, but honestly, with the IBIS on the R5 combined with the lens stabilization, I was pulling off hand-held shots at half a second or longer without any blur. Plus, for those massive canyon views, that extra 1mm on the wide end makes a surprisingly huge difference compared to the Canon RF 15-35mm f/2.8L IS USM. It captures so much more of the sky and foreground. I almost went the adapter route with the Canon EF 16-35mm f/2.8L III USM because I found a deal, but the bulk just isnt worth it on the R system. The RF glass is just sharper across the frame. If you're shooting landscapes, you're usually stopped down to f/8 or f/11 anyway to get everything in focus, so paying extra for f/2.8 just for those blue hour moments doesnt make sense to me anymore. I've had zero complaints with the f/4 version and it fits perfectly in my bag with room to spare.
