To add to the point above: it is absolutely a tank! I carried that Sigma Art beast through the Swiss Alps once and my neck was legit screaming by day three... no joke. Looking at the convo so far, you're basically choosing between the heavy/sharp Sigma Art and the light Tamron G2. But if you're budget-focused for Japan, you gotta check out the Sigma 28-70mm f/2.8 DG DN Contemporary. It is incredibly light and usually goes for around $800. I love it because the technical specs are amazing—you get that f/2.8 speed but it feels like nothing in your bag. I used the extra cash I saved to buy a nice Peak Design Slide Lite Camera Strap and a ton of street food! Basically, you get the performance without the back pain or the high price. Definitely the smart move for a hiking trip imo.

In my experience shooting Sony for over a decade, you really want something that wont fail you or break your back on the road. I've tried many of these zooms and the Sigma 24-70mm f/2.8 DG DN Art is definitely the sharpest, but it weighs a ton. After hiking for a few hours in Japan, you'll feel every gram of that thing. It can be a real burden when you're trying to enjoy the shrines. I usually suggest the Tamron 28-75mm f/2.8 Di III VXD G2 as the smarter choice for travel. Its lightweight and reliable, though you lose that wide 24mm view for cramped city streets. If you want the safest all-rounder tho, the Sony FE 24-105mm f/4 G OSS is basically legendary. The f/4 is slower, but having that extra reach and stabilization has saved my shots many times. For a one-lens trip, its the one I'd trust most.

I've spent way too much money trying to find the perfect travel lens over the years, and honestly, the spec sheet doesn't tell the whole story. When you're hiking all day, every ounce matters more than a tiny bit of extra sharpness you'll only see if you're pixel peeping.

• Tamron 28-75mm f/2.8 Di III VXD G2: This is the sweet spot for your budget. I used the first version for years and the G2 is a massive upgrade in terms of focus speed. It's super light for hiking. The only real downside is that 28mm isnt quite wide enough for some temples or tight city streets... those 4mm at the wide end make a bigger difference than you'd think when you're trying to capture a whole building.
• Sigma 24-70mm f/2.8 DG DN Art: The glass is incredible and sharp as a tack. But it's almost 300g heavier than the Tamron. I took it on a trip to the Rockies once and ended up leaving it in the hotel room halfway through because it was just too much to carry on long trails. Plus, some of the older copies had issues with dust getting behind the front element, though the newer ones seem better sealed.
• Sony FE 24-105mm f/4 G OSS: Since you're traveling, don't sleep on this one. It's right in your budget. You lose one stop of light compared to the f/2.8s, but having that extra reach at 105mm is amazing for details and portraits. The built-in stabilization (OSS) is great if you plan on doing any handheld video too. In my experience, you'll appreciate a lighter bag more than a slightly sharper corner when you're walking 20k steps a day in Japan. If you really need that f/2.8 for low light, get the Tamron. If you want more range, the 24-105 is the way to go.

@Reply #3 - good point! That Sigma 28-70 is definitely light, but unfortunately I had issues with mine after just a bit of light drizzle. The weather sealing just isnt as good as expected for a serious travel lens, which is a huge bummer because the size is perfect. If you're hiking around Japan, you're almost definitely gonna hit some rain or humidity. Adding my two cents... if reliability is your main thing, you might actually want to look at the Sony FE 24-105mm f/4 G OSS. I know its not f/2.8, but it is built like a tank and wont let you down. The extra reach is also a lifesaver when you cant move your feet to get the shot. Quick tip: If you go with the Tamron, make sure to use the USB-C port to update the firmware to the latest version before you leave. It fixes some focus breathing issues that used to annoy me. Japan is gonna be incredible, you'll have a blast shooting there!