Curious about one thing: what kind of filters are you planning to use? Honestly, when shooting coastal scenes with the Sony Alpha a7R IV, salt spray is a major risk for that 61MP sensor. Before I suggest the Tamron 17-28mm f/2.8 Di III RXD as a budget-friendly, internal-zooming (safer!) option versus the Sony FE 20mm f/1.8 G, I need to know if you're using screw-ins or a square system. Let me know!

Curious about one thing: what's your actual budget for these glass upgrades? The Sony FE 16-35mm f/2.8 GM II is technically the gold standard, but it's pricey. If you're looking for cost-effective alternatives that still resolve 61MP, I've got some ideas:

1. Sigma 14-24mm f/2.8 DG DN Art for Sony E - incredible corner sharpness for around $1,300.
2. Tamron 17-28mm f/2.8 Di III RXD - great weather sealing and much cheaper, usually under $900.

Let me know your price range!

In my experience, shooting with the 61MP sensor on the a7R IV is a total game-changer, but yeah, it absolutely punishes mediocre glass! For your coastal treks, I seriously recommend the Sony FE 16-35mm f/2.8 GM II. It's way sharper than the first version, especially in the corners where the high resolution usually reveals soft spots. The weather sealing is fantastic too, which is a must for salt spray.

If you're gonna be hiking for miles and want to shed weight, the Sony FE 20mm f/1.8 G is actually incredible. Honestly, its resolving power is mind-blowing for a G-series lens—it holds up to the 61MP sensor better than many older primes! You wont regret either, but the zoom's versatility is amazing for framing tide pools. Hope this helps!

Basically, I totally agree that the a7R IV is a total beast that demands perfection, but there's a DIY side to this that a lot of folks overlook. You can buy the best glass in the world, but on a 61MP body, even a tiny bit of element misalignment or a dirty sensor is gonna show up immediately in those big prints. I've found that self-servicing and testing is the only way to stay sane. Here is what I do to make sure my gear actually hits those MTF benchmarks:
- Do a DIY decentering test immediately. Shoot a distant subject at the center and all four corners to ensure the elements are perfectly aligned. This sensor is brutal on "copy variation" and even a GM can have issues.
- Master your own sensor cleaning. With coastal shooting, you're gonna get salt spray and grit; sending it for professional service every time is a waste of money when you can do it safely at home with a good kit.
- If your using adapters, check the flange distance accuracy. Even a fraction of a millimeter off will kill your edge-to-edge sharpness. If your looking for another prime, the Sony FE 24mm f/1.4 GM is incredible for its weight. Tbh, it's one of the few lenses that feels like it was actually built for this resolution.

Stumbled on this thread and it really hits home. Shooting high res near the ocean is a whole different beast. Reminds me of this one trip I took to the rugged cliffs up north. I had just gotten a new high-end body and was so terrified of the salt air that I basically babied it the entire time. I remember staying up half the night before just checking the seals on my bag and making sure I had enough microfiber cloths. When I finally got to the edge of the water, the wind was howling so hard it was literally blowing the tripod over. I spent about two hours just fighting with my jacket to create a windbreak and never actually managed to frame a single shot. My buddy was with me just snapping away with his old film camera not caring at all, while I was obsessing over every little drop of mist. We ended up losing the light because I was so distracted by a weird clicking sound in my tripod head that turned out to be just a tiny pebble. Total nightmare of a morning, but man, the coffee at the trailhead afterwards was legendary... definitely made the failed shoot feel a bit better.

Facts.

So I've been shooting with the R series for a long time now and honestly I spent way too much money early on trying to chase every new GM release just to feed that sensor but I eventually realized that for the way I shoot landscapes—mostly stopped down to f/8 anyway—some of the budget lenses actually hold up way better than people give them credit for. I've had the Samyang AF 24mm f/1.8 FE in my bag for like two years now and even though it feels kinda plasticky compared to the Sony glass it’s surprisingly sharp even on my a7R IV and it weighs basically nothing which is a lifesaver on those long coastal hikes. I actually picked mine up used for a total steal and it's been my workhorse while my expensive zooms mostly just sit in the cabinet because I'm way less stressed about it getting hit by salt spray or sand. You just gotta be careful with the quality control on those third-party primes and maybe test a couple copies but once you get a sharp one it’s hard to justify the extra $1k for the name brand stuff especially when you're just gonna be beating it up in the elements anyway tbh.

Re: "In my experience, shooting with the 61MP sensor..."

• Spot on! That sensor is amazing but it definitely makes you realize how much your old lenses were struggling. I love it tho because when you hit that focus perfectly it looks incredible! Reminds me of my trip to the coast last year where I was so focused on the gear that I totally forgot to check the tide charts and almost got my car stuck in the sand. It was this bright red Jeep and honestly the color was the only reason the tow truck found us. Best part was the driver had like six dogs in the cab with him and they were all super friendly. I ended up spending more time playing with the golden retriever than actually shooting the sunset. Those dogs were definitely the highlight of the weekend for me! Anyway sorry kinda went off topic there lol.

Saving this whole thread. So much good info here you guys are awesome.

Great info, saved!