Adding my two cents here because those Zion hikes can get brutal if your packs too heavy. I would suggest being cautious about the technical trade-offs with the Canon RF 14-35mm f/4L IS USM. While that extra 1mm at the wide end sounds minor, it actually provides a significantly wider field of view for those big canyon walls. However, make sure to look at the raw files before corrections; it relies heavily on digital processing to fix massive vignetting and barrel distortion at 14mm. Ngl, the uncorrected corners are basically black at the widest setting. I would suggest comparing these specific technical points before you buy:

• Weight and Portability: The f/4 version is roughly 540g compared to the 840g of the f/2.8 zoom. Carrying an extra 300g up to Angels Landing is definitely something you will feel by the afternoon.
• Optical Quality: Honestly, the Canon RF 15-35mm f/2.8L IS USM is more consistent across the frame at wider apertures. The f/4 is sharp, but it really peaks around f/8 for landscape work.
• Astro Potential: If you think youll ever want to shoot the Milky Way, you might want to consider the Canon RF 16mm f/2.8 STM as a tiny, lightweight prime to supplement the f/4 zoom if you go that route. If youre strictly on a tripod at sunrise, the f/4 is basically a no-brainer for saving weight. But if you really want that gold standard feel, the f/2.8 is the one to beat... just be prepared for the extra bulk and the price tag.

^ This. Also, summarizing the thread... basically it is weight vs aperture. I am really happy with the f/4 and havent had any complaints. To save cash:

• Find a refurbished Canon RF 14-35mm f/4L IS USM
• Grab a tiny Canon RF 16mm f/2.8 STM for astro This setup works well and is lighter! Let me know if you need help finding gear deals.

Jumping in because I'm having the exact same struggle and it's honestly frustrating. I've been looking at the MTF charts for the Canon RF 14-35mm f/4L IS USM and the native distortion is just brutal... like almost 10% at 14mm. It's disappointing that we're paying L prices for glass that relies so heavily on digital stretching. I've had issues with corner smearing on my R5 when doing my own lens profiles too. Since I'm also trying to figure this out without spending a fortune, here are a couple quick tips:

• Check out the Sigma 14-24mm f/2.8 DG HSM Art for EF mount. Use it with the Canon Mount Adapter EF-EOS R. The technical specs on the Sigma are way better than the RF zooms for landscape.
• If you're tech-savvy, try building a custom profile in Adobe Lens Profile Creator instead of using the built-in Canon one; it handles the 14-35mm's stretch way better. It really shouldn't be this hard to find a wide zoom that doesn't compromise on raw optical quality.

Be careful choosing the f/4 zoom if you have any interest in astro while youre in Zion. While its lighter for hiking, that extra stop is critical for keeping sensor noise down at night. I would suggest checking a few technical specs first:

• Corner sharpness at f/4 versus f/5.6
• Flare resistance when shooting into the sun
• Physical weight versus your tripod capacity Basically, dont ignore the light gathering loss just to save a few grams... you might regret it during blue hour.

Before you pull the trigger, how much of this trip is actually gonna be dedicated to astro vs daytime landscape? If it's mostly sunrise on a tripod, you're fine with f/4, but there's a third option that might be better than both RF zooms for your budget. I've been extremely happy using the Canon EF 16-35mm f/2.8L III USM with an adapter on my R5. It's a tank and honestly performs better than the RF 14-35mm in terms of raw optical quality without relying on software.

• You get f/2.8 for the night shots without the huge RF price tag.
• No weird digital stretching in the corners like the 14-35mm has.
• Fits easily under your $2k budget even if you buy it mint. The only real downside is the extra length with the Canon Mount Adapter EF-EOS R, but for Zion, the reliability is worth it. It's been my go-to for years and I still havent found a reason to swap to the native RF version tho. It just works and the files are super clean.

Building on the earlier suggestion about the EF adapter route, I unfortunately have to agree that the current RF lens pricing is quite steep for what you actually get. Its disappointing that we are expected to pay premium prices for glass that relies so heavily on software to look decent. I bought into the R5 system expecting more accessible wide-angle options under two grand, but it hasnt really happened yet for native L-series zooms. Since you want to keep the budget tight for Zion, here is a practical setup that wont break the bank:

• Buy a used Canon EF 16-35mm f/4L IS USM for your tripod work.
• Use a Canon Mount Adapter EF-EOS R which is super reliable.
• Pick up a Canon RF 16mm f/2.8 STM specifically for your night sky shots. I had issues with the 14-35mm f/4 feeling a bit overpriced for the build quality, and the raw files were just not as good as expected before digital corrections. Taking the EF route saves you enough money to actually enjoy your trip without stressing about the gear debt. It is not as sleek as a single RF zoom, but for long-term ownership, the value is just much better.

> Does that extra stop of light really matter if Im mostly on a tripod at sunrise? Honestly, be super careful with the f/4 zoom tho! I totally disagree with the idea of just relying on software to fix those images later. Zion is literal magic and you dont want to get home only to find out your corners are muddy because the digital corrections stretched them too far! If youre on a tripod at sunrise, sure, f/8 is king. But what about when the wind kicks up in the Narrows and you need a faster shutter speed to freeze motion? I had a lens fail me once because I thought weight was everything, and man, I regretted it so much. Stick with the high-end glass if you can swing it! The build quality on the f/2.8 is just on another level and much more reliable when you're out in the elements for a week straight. Plus, changing lenses in the desert? Such a bad idea. Dust is gonna get all over that R5 sensor if you try to swap between a zoom and that tiny prime mentioned above. Stick to one amazing, weather-sealed lens and call it a day! You wont regret the extra weight when you see those crisp shots!

Great info, saved!