Like someone mentioned, the 35mm and 50mm primes are usually the go-to, but if you want something that actually stays glued to your R6 without adding bulk, you should look into the Canon RF 16mm f/2.8 STM. Over the years, I have tried many lenses for urban work, and honestly, the pancake design is a game changer. It is incredibly sharp for the price and barely sticks out from the body. In my experience, wide-angle street shots capture way more of the NYC energy anyway. If you need something slightly more standard, the Canon RF 28mm f/2.8 STM is another solid choice that is super reliable. It wont draw nearly as much attention as a giant zoom lens, which is crucial when you are trying to stay low-profile out there.

TL;DR: Grab the Canon RF 50mm f/1.8 STM for the ultimate budget king or the Canon RF 35mm f/1.8 Macro IS STM if you want better versatility. I totally get the zoom lens struggle. Walking around NYC with a brick attached to your camera gets old fast. For street work on an R6, I have been really happy using the pancake fifty. Honestly, the Canon RF 50mm f/1.8 STM is basically a no-brainer. It is dirt cheap, super sharp, and so small you can basically hide the whole setup in a jacket pocket. The focus is quick enough for candid shots and you will be way less conspicuous than with that bulky zoom. If you want something a bit wider, check out the Canon RF 35mm f/1.8 Macro IS STM. It is slightly pricier but still well under your six hundred dollar limit. I love the 35mm focal length for city streets because it captures more of the scene without needing to back up constantly. The main perks here are the image stabilization and the really solid build quality. It works well in low light, which is crucial if you are out during golden hour or into the evening. Both of these have served me well, and I have had zero complaints with their performance on the R6 sensor. Let me know if you want to see some sample shots or need tips on settings for the street!

Big if true