Honestly, that 61MP sensor on the a7R V is a bit of a double-edged sword because it shows every tiny flaw in your glass. I took a similar high-res setup to Zion last year and man, my legs were feeling it after the first day... you definitely want to be careful about carrying too much weight up those trails like Angels Landing. The zoom isnt really a compromise anymore with the newer tech, but that price tag is definitely something to think about. I would suggest looking at these options to save some money for your travel costs instead of dumping it all into one lens:

• Sony FE 20mm f/1.8 G is super light and actually handles the high res sensor better than some expensive zooms.
• Sigma 16-28mm f/2.8 DG DN Contemporary for Sony E is way cheaper than the GM and much easier to hike with.
• Sony FE 16-35mm f/4 G PZ if you dont mind a slower aperture, its incredibly sharp and tiny. Make sure to check the used market because you can often find the first Sony FE 16-35mm f/2.8 GM for way under your budget. It might be slightly heavier than the new one, but it still takes gorgeous shots. Just be careful with the 14mm prime tho... its a very specific look and you might find it way too wide for everything in the canyon. If you need any more tips on what else to pack for the trip, just ask.

Unfortunately, the price on that GM II is just disappointing. I had issues with corner sharpness on high-res sensors that really annoyed me... it just isnt worth it. You dont need to blow $2500 for Zion. Grab these instead:

• Sony FE 20mm f/1.8 G has better resolving power than most zooms and weighs nothing.
• Sigma 16-28mm f/2.8 DG DN Contemporary is way lighter and cheaper tho.

> I'm confused if the zoom is actually a compromise. Lens prices are honestly such a scam lately given the poor reliability. Are you planning on shooting astro or just day hikes tho?