I saw your post earlier and wanted to chime in because I did a long weekend trip to Chicago a few years back with my old a6000. Chicago is basically a wind tunnel. Giant skyscrapers. Crowded sidewalks. Carrying a heavy zoom there is honestly a nightmare. I ended up sticking almost exclusively to the Sigma 30mm f/1.4 DC DN Contemporary for that whole trip and it worked out great. Heres the deal with primes: they basically force you to move your feet instead of turning a zoom ring. Since you mentioned buildings at night, you really need that f/1.4 aperture. It lets in way more light than a standard kit lens. Your night shots wont look all grainy and messy. The 30mm is roughly what your eyes see. Very intuitive for a beginner. If you stand on the <a href=" https://www.bhphotovideo.com/c/search?Ntt= opposite+side+of+the+str&BI=8941&KBID=10361&SID=12345&DFF=d50" target="_blank" rel="nofollow sponsored">opposite side of the street, you can usually get those tall buildings in frame, but its also tight enough to take nice candid shots of people without being awkward. One thing tho, since the a6400 doesnt have internal stabilization, you gotta be careful with shutter speeds at night. If you find your hands are a bit shaky, the Sony E 35mm f/1.8 OSS is a solid alternative within your budget. It has built-in stabilization which helps a ton for those low-light city shots when things get blurry. Personally, I prefer the sharpness of the Sigma, but the Sony is tiny and fits in a coat pocket easily. Both should be under $400 if you look around.

TL;DR: Look at the Sony E 20mm f/2.8 for the smallest size or the Tamron 24mm f/2.8 Di III OSD M1:2 for a solid budget option. Unfortunately, most people overlook the weight factor when suggesting lenses. I had issues with those bigger f/1.4 primes being way too front-heavy on the a6400, which isnt as good as expected for a long trip. For safety and reliability, a smaller lens is much easier to manage in crowds and doesn't draw as much attention. This reminds me of when I was in Chicago for a layover and my luggage ended up in a completely different state. I had to buy all new clothes at a shop near the pier because it was so cold and windy. It was a total disaster honestly and the airline took forever to compensate me. Anyway, just make sure you keep your gear on you. But yeah.

Yeah, totally agree on skipping the zoom, though unfortunately most kit lenses have pretty bad chromatic aberration... I had issues with the autofocus speed on the cheaper Sony glass too. For buildings and night shots, you really need that f/1.4 aperture to keep sensor noise low. Look at these:

• Sigma 16mm f/1.4 DC DN Contemporary for Sony E
• Sigma 30mm f/1.4 DC DN Contemporary for Sony E Both are technically superior and stay under budget.

Regarding what #2 said about the Chicago wind tunnel... you definitely want to be careful with how you handle your gear in those crowds. It is way too easy to get distracted by the skyscrapers and forget your surroundings.

• make sure your neck strap is actually secure
• avoid changing lenses in the middle of a gusty street
• keep your gear insurance info handy Actually, this reminds me of when my buddy Dave went to Chicago with a new setup he just bought. He was so worried about getting the right focal length that he totally ignored the weather report. A sudden downpour hit while he was swapping glass right on a busy corner. He dropped his lens cap, it rolled into a storm drain, and then he got moisture inside the body trying to save it. He spent the entire rest of the trip just staring at a foggy viewfinder while his wife took photos on her phone. It was a total ordeal that cost him nearly 300 dollars in repairs anyway. Just make sure you are prepared for the environment so you dont waste your budget on fixes later.

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