So I've been shooting with my D750 for about six years now, mostly doing portrait stuff with my trusty 85mm prime and the heavy 70-200 f2.8. But I've got this trip to Japan coming up in three weeks, and my back just cannot handle lugging around a bag full of heavy glass anymore. I need to consolidate down to just one single lens that can stay on the body the whole time.
Normally I'd just grab a 24-70 but I feel like I'll miss the extra reach for street details, and the f2.8 version is still a brick. I've been looking at the 24-120mm f4 VR, but I'm worried the low light performance in Tokyo at night is going to bum me out since I'm so used to fast primes. Budget is around 800 bucks, totally fine buying used. I actually borrowed a friend's 28-300mm superzoom to test out last weekend, but the image quality on the long end was way softer than I expected, even stopped down to f8. It just felt really mushy.
What is actually the best balance of range, weight, and sharpness for a Nikon FX body when you can only bring one lens?
Late to the party here, but I wanted to chime in because I did a similar Japan trip with a D750. You might want to consider a slightly different strategy than just one single heavy zoom, especially since you are so used to that 85mm look. I would suggest looking at the Nikon AF-S NIKKOR 24-85mm f/3.5-4.5G ED VR. It is way lighter than the 24-120mm (only about 465g) and you can find them used for under 300 bucks. To solve your low light anxiety in Tokyo, pair it with a tiny prime like the Nikon AF-S NIKKOR 50mm f/1.8G. The 50mm weighs basically nothing and easily slips into a pocket. When the sun goes down, you just swap to the prime. Be careful with third-party f/2.8 zooms like the Tamron SP 24-70mm f/2.8 Di VC USD G2. While the optical quality is fantastic and it fits your budget, it still weighs around 900g. That pretty much defeats the purpose of saving your back. Make sure to check out the DXOMARK lens database for sharpness scores on the D750, and browse the Fred Miranda buy/sell forums for used deals. You can grab both the 24-85 and the 50mm way under your 800 dollar budget.
Regarding what #2 said about a different strategy, in my experience over the years, the Tamron 35-150mm f/2.8-4 Di VC OSD is a killer compromise. You'll get that fast f2.8 at the wide end for night shots, and the focal range is perfect for street details. Check MPB or KEH for used deals, they usually have them way under your budget. Let me know if you want links to check the sharpness specs!
Go with the Nikon AF-S NIKKOR 24-120mm f/4G ED VR. Having run this setup on my D750, the constant f4 aperture keeps the weight at 710g, which is pretty manageable. The D750 handles ISO 3200 and 6400 incredibly well, so the f4 speed isnt really an issue at night in Tokyo, especially with the VR offering 3.5 stops of stabilization. You can easily grab a clean used one for around 450 bucks.
