Wow, you picked a total beast of a camera! The R5 is amazing for landscape work because of that 45MP sensor. Since you want to save money but still get pro results in Iceland, definitely check out the Canon RF 14-35mm f/4L IS USM. It is much more affordable than the f/2.8 version and honestly, for landscapes, you are usually shooting at f/8 or f/11 anyway so the extra aperture doesnt even matter. It is super wide which is perfect for those massive waterfalls! If you want to be really budget-conscious, grab the Canon Mount Adapter EF-EOS R and a used Canon EF 16-35mm f/4L IS USM. It is a legendary lens and you can find them for a total steal now. This setup is fully weather-sealed too, which is huge for the Icelandic rain. You really wont need to swap lenses in the snow if you just keep a versatile wide zoom like that on the body!

Unfortunately, the 14-35mm recommended earlier has some pretty disappointing distortion at the wide end. I would go with the Canon RF 15-35mm f/2.8L IS USM for better corner performance, or the Canon RF 24-105mm f/4L IS USM if you want to avoid swapping lenses in the rain. Check out the lens comparison tool on The-Digital-Picture... the technical data really shows the difference in glass quality.

Honestly it drives me crazy how expensive this stuff has gotten lately! I love the R5 specs because that sensor is just amazing but the lens market is such a scam right now! Obsessing over MTF charts and technical data for years only led me to realize everything costs a fortune. It is so exhausting trying to keep up with these prices just for a vacation! Total gear fatigue!

Like someone mentioned, the 24-105mm is a solid shout, but I honestly think it is the only lens you actually need for this. I have been shooting with the RF 24-105mm f/4L for a while now and I am incredibly satisfied with how it performs on the R5. I know the 15-35mm is tempting for those huge views, but for a beginner in Iceland, keeping things simple is way better. You really dont want to be changing lenses when the wind is whipping volcanic sand everywhere... trust me. The image quality is fantastic and it works well for everything from wide vistas to tighter shots of the horses or distant peaks. Plus, it leaves you with nearly a thousand dollars of your budget left over. If you want to save even more, this extension is great for finding the best prices on gear. I have no complaints about the sharpness or the weather sealing on this one. It is a true workhorse that lets you focus on the scenery instead of your camera settings. Just get the one lens and enjoy your trip without the gear fatigue.

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