im literally leaving for my tokyo trip in four days and i still havent picked a prime lens for my a7IV. its stressing me out big time. i spent all night looking at the 35mm f1.8 because its cheap and light for walking around shibuya but then i keep seeing people say the 35mm GM is the only way to go for the sensor quality. the GM is way over my $900 budget though and looks way too heavy for a whole day of walking. i also saw the 40mm f2.5 mentioned for being tiny but im worried that aperture isnt fast enough for night street shots. i need to buy something tomorrow to get it in time. what do i actually get...
Honestly, picking a lens right before a big trip like Tokyo is a recipe for regret, but i get the stress. You are right to worry about the GM weight. Its a total beast to carry around Shibuya for 10 hours and will definitely hurt your neck by day two. Unfortunately, the options in your budget all have annoying trade-offs and arent as good as people make them out to be.
- Sony FE 35mm f1.8 is the most logical choice for your budget, but the build quality is kinda plastic and the bokeh isnt nearly as smooth as youd want. I had issues with purple fringing on high-contrast night signs in Shinjuku with this one. It works, but it feels like a compromise every time you look at the raw files.
- Sony FE 40mm f2.5 G is beautiful and tiny, but f2.5 is just not as good as expected for low light. If you are hitting the Golden Gai back alleys at night, you are gonna be pushing that a7IV sensor way harder than necessary. Its disappointing for anything other than broad daylight.
- Sigma 35mm f2 DG DN Contemporary is actually what i would grab. Its built way better than the Sony 35mm f1.8 and stays under your budget. It has a physical aperture ring which is great for street work. I wouldnt bother with the 40mm if you care about night shots. Just get the Sigma 35mm f2 DG DN Contemporary or the Sony 35mm f1.8 and accept that it wont be GM quality. The Sigma feels way more premium tho.
