Regarding what #1 said about the Canon RF 14-35mm f/4L IS USM, it is a solid pick, but if you want zero distortion for architecture, look at the Canon RF 15-35mm f/2.8 L IS USM. Ngl, the corner softness is exaggerated; it is razor sharp for landscapes. If you need astro, get the Samyang AF 14mm f/2.8 RF for cheap. It is lowkey a beast for stars and saves you a ton of cash.

I totally feel your pain—I spent the last two weeks obsessing over this exact dilemma before finally pulling the trigger on a new setup. I'm no expert, but I went down the rabbit hole of forum posts and sample galleries until my eyes glazed over. For landscape work on the R5, I kept looking at the Canon RF 14-35mm f/4L IS USM because the weight difference compared to the 15-35mm is honestly huge when you're out on the trails all day. People get so hung up on the software correction, but honestly? Once I saw the files in post, it just doesn't matter for 99% of landscape shots. It's sharp where it counts. However, if you're really worried about the distortion for architecture and just can't shake the feeling that you need something 'pure,' I actually looked at the Canon RF 35mm f/1.4 L VCM for those times when you need a bit more light and want to avoid the zoom distortion entirely. It’s obviously not as wide, but for interiors, you can always do a quick pano stitch if you need a wider field of view. I ended up deciding that the convenience of the zoom outweighed the perfectionist urge for the absolute sharpest corners at 14mm. If you aren't printing massive gallery-sized prints, you're going to be perfectly happy with the 14-35mm—it's just way more fun to carry around while you're actually out exploring.

• Grab the Canon RF 14-35mm f/4L IS USM and save cash for a dedicated fast prime for astro; it is plenty sharp for your landscape work.

Honestly, seeing everyone throw around the usual RF zoom recommendations is getting a bit old—they’re all heavily optimized through software, which makes me feel like I’m paying a premium for digital correction rather than optical perfection. If you’re really worried about those soft corners on a 45MP sensor, relying on a zoom that needs a 'digital band-aid' is just going to frustrate you long-term. I’ve been shooting landscapes for years, and I stopped chasing the 'all-in-one' zoom dream because the weight is always a compromise and the edges are almost never perfect. Since you’re doing architecture, you really want to avoid that aggressive barrel distortion in the first place. You should look into these instead:

• Voigtlander Super Wide-Heliar 15mm f/4.5 Aspherical III (It’s manual focus, but for landscape/architecture, that’s actually a benefit—the build quality is worlds ahead of the plastic RF stuff, and the sharpness is legit edge-to-edge.)
• Sigma 14-24mm f/2.8 DG DN Art (Wait, no—I mean, you said no adapters, and you're right, they're a pain. But honestly, if you can find a used copy, the image quality here absolutely destroys the RF 15-35mm for way less money.) If you really want to stay native and hate the idea of software correction, stop obsessing over the zooms. You’ll get way more satisfaction out of a prime that’s built to actually resolve detail rather than just look good on a spec sheet.

To add to the point above: I was hiking the Enchantments last July with the Canon RF 15-35mm f/2.8 L IS USM and, honestly, the weight started feeling like a boat anchor by mile ten. The constant swapping of lenses and the sheer bulk of that glass made me realize I was missing shots because I was too tired to set up the tripod properly. I ended up selling it and picking up the Canon RF 16-35mm f/4L IS USM equivalent in performance through the Canon RF 15-30mm f/4.5-6.3 IS STM for casual days, but for your specific architecture needs, I shifted to the Canon TS-E 17mm f/4L. It is a manual focus shift lens, but for architecture, it is the gold standard. You avoid all that software-corrected distortion because the optics handle the geometry for you. If you really want that crisp 45MP landscape look, stop worrying about the f/2.8 zoom and look at the Canon RF 14-35mm f/4L IS USM for the convenience, or embrace a prime like the Canon RF 24mm f/1.4L VCM if you want that extra light for astro. Summary: The consensus here is split between heavy, corrected zooms and specialized glass. If you prioritize architecture, look into tilt-shift lenses to bypass digital corrections. If you hike, the f/4 zooms are superior in weight, and you can easily compensate for the lack of light in astro through stacking. Ditch the zoom if you want true architectural precision.

> Is the 15-35mm really as sharp as people claim for landscape work, or am I better off grabbing the 14-35mm and just dealing with the profile corrections? Building on the earlier suggestion, I went through this exact mental tug-of-war last year when I was shooting the coast. I spent months lugging heavy gear until my shoulders basically quit on me. I finally realized that for my style, the extra stop really only mattered when I was doing deep-sky stuff at night. For everything else, I was just carrying extra weight for no reason. I ended up picking up the Canon RF 15-30mm f/4.5-6.3 IS STM for a while, but eventually settled on the versatility of primes. If you want true architectural perfection without the software gymnastics, stop overthinking the zooms and just grab the Canon RF 16mm f/2.8 STM. It's so light you'll forget it's in your bag, and it leaves plenty of room in your budget for a dedicated astro lens later.

This thread is gold. Bookmarking for future reference 🔖

Just catching up on this thread. This comes up a lot, but the consensus usually boils down to whether you prioritize weight for trekking or light for night work. Like someone mentioned, the distortion vs. sharpness debate is basically a constant trade-off in the RF ecosystem. My personal experience:

• I switched to a lighter setup three years ago after carrying heavy glass through the Cascades ruined my back for a week.
• I learned that for 90% of my landscape work, the aperture difference is negligible when using a tripod.
• I eventually accepted that modern software profiles fix most wide-angle geometry issues before I even start editing. Ultimately, if you are hiking all day, cut the weight. If you are shooting interiors or astro, you know the physical requirements. Don't overthink the glass; focus on the shot.

Everyone pushes the RF zooms, but honestly, you are paying a massive premium for the brand. If you want actual sharpness on that 45MP sensor, look at these instead:

• Canon RF 16mm f/2.8 STM: Tiny, cheap, and surprisingly sharp in the center.
• Laowa 12mm f/2.8 Zero-D: Better for architecture than any RF zoom because it lacks the heavy barrel distortion. Native convenience isn't worth soft corners. Stop chasing hype and buy better optics.

Yep been there done that. Can confirm everything said above is spot on.

Look, I spend all day dealing with tolerances that have to be within a thousandth of an inch, so I have zero patience for this 'software correction' nonsense people keep pushing. You buy a lens to project an image onto the sensor, not to have a computer redraw half the frame because the glass was built cheap. Listen, you are stressing over the wrong things. If you are doing architecture, barrel distortion is the enemy of a clean build. Period. You dont want a lens that needs a digital band-aid to look straight.

• Stop worrying about the extra stop for astro. You can always do a longer exposure or stack frames. You cant fix soft edges after the fact.
• Focus on the physics. If the glass isnt right, the software is just lipstick on a pig.
• If you are hiking, lighter is always better. My back knows that better than anyone. Honestly, if the native options are leaving you second-guessing, just pick the one that handles the weight best and accept that at this resolution, every lens has a weak point. Nothing is ever perfect, in the shop or in the field. Just pick one and get out there to shoot. You are wasting time debating specs when the light in the PNW wont wait for you to decide.

Noted!

Works great for me