Congrats on the 5D4, its a total workhorse but yeah, that jump from a Rebel is no joke when it comes to weight. In my experience, do not even bother with that narrow neck strap it came with unless you want a chiropractor bill after day one. I have tested basically every carrying method over the last decade and for a heavy full-frame setup, the Peak Design Slide Camera Strap is the way to go. It uses seatbelt-style webbing that actually distributes the load across your shoulder. The Peak Design Capture Camera Clip v3 is technically rated for the weight, but honestly, with a Canon EF 24-70mm f2.8L II USM attached, it makes your backpack feel totally lopsided. For the long exposures in Iceland wind, you need mass but you dont want a 10lb tripod. I usually suggest the Sirui T-1205 Travel Tripod with E-10 Ball Head because it hits that sweet spot of carbon fiber vibration dampening without the RRS price tag. It handles about 22lbs, which gives you a good safety margin for the 5D4. Skip the battery grip for travel. Its just more bulk to cram into your bag. Just grab three or four Canon LP-E6NH Lithium-Ion Battery packs and keep them in an internal pocket close to your body heat. The cold will kill your voltage faster than the sensor readout will. Also, for the L-bracket, dont overthink it. The SmallRig L-Bracket for Canon 5D Mark IV 2117 is specifically machined for the 5D4 chassis and has a sliding side plate so you can actually plug in your remote shutter without it hitting the tripod head.

Re: "Congrats on the 5D4, its a total workhorse..."

• Are you planning on using a wired remote for those waterfalls? Port access is tricky with generic brackets.
• Skip the battery grip. It's too bulky. Just get a Wasabi Power Battery 2-Pack for Canon LP-E6N.
• The Sunwayfoto PCL-5DIV L-Bracket fits perfectly without blocking your side ports.
• For the tripod, check the Manfrotto BeFree Advanced Aluminum Travel Tripod. It handles that heavy 24-70 lens without too much vibration.

Honestly, I had a pretty rough time trying to gear up for a similar trip last year. I bought the 3 Legged Thing QR11-LC Universal L-Bracket because people said it was a great value, but unfortunately, it was a total mess on my 5D4. It constantly wiggled and blocked my remote cable port, which is basically the last thing you want when you are standing in front of a waterfall. For carrying, I tried the Op/Tech USA Pro Loop Strap because everyone raves about that neoprene padding. Ngl, it was not as good as expected for a heavy body. While the padding is thick, it has this bouncy stretch that actually made the camera feel heavier when I was hiking. It just didnt feel secure at all. Tripod-wise, I tested the Sirui T-025SK Carbon Fiber Tripod hoping to save some weight in my carry-on. Big mistake. In even a light breeze, it was vibrating like crazy with my 24-70mm lens attached. It just couldnt handle the top-heavy setup. I ended up having to hang my bag from the hook just to keep it from tipping over, which was super frustrating. TL;DR: Skip the universal brackets and ultralight tripods. The 5D4 is a tank and it will just bully gear that isnt sturdy enough.

I am literally in the exact same boat right now lol. I just grabbed a 5D4 for a trip and man... the weight is such a shock after years with a Rebel. I am super happy with the camera so far but the accessory hunt is honestly so overwhelming. Like someone mentioned, the costs just keep piling up. 400 bucks sounds like a lot but it disappears fast. I have been looking into the K&F Concept 64 inch Carbon Fiber Camera Tripod since it seems like a solid budget option that is actually reliable, but I am still nervous about it being sturdy enough for that heavy glass. It is such a struggle trying to balance being prepared with not spending a fortune. I am also stressing about the batteries for long exposures... totally feeling your pain on this one!

Late to the thread here, but I've used the 5D line for years and weight management is always the primary concern for travel. In my experience, using a standard neck strap with a heavy body and 2.8 glass is a recipe for physical fatigue. You really need a system that distributes that load across your shoulders or hips. Regarding the tripod, Iceland's wind is no joke. A lightweight setup might be easy to carry, but it can be useless for long exposures if it isn't stable. I've tried many configurations over the years and skipping the battery grip is usually the smarter move to save weight. Before looking at specific gear, what kind of terrain are you actually covering? Are you mostly shooting near the car, or doing serious hiking? Also, does your $400 budget need to cover both the tripod legs and a ball head?