Best Sigma lens for FUJI X-T4?

Building on the earlier suggestion to look at those f/1.4 primes, I honestly think you should look at the Sigma 23mm f/1.4 DC DN Contemporary for Fujifilm X instead. Just saw this thread and felt I had to mention it because its newer and the 35mm equivalent field of view is way more versatile for street photography than the 30mm or 56mm options. Landscapes often need that bit of extra width too. Over the years ive found that a 35mm equivalent strikes the best balance for a single lens setup. Technically speaking the 23mm is better optimized for fujis 26mp and 40mp sensors. Better contrast wide open and way less chromatic aberration in high contrast street scenes compared to the older 30mm design. It usually retails around $549 so it fits your $800 budget perfectly with plenty of cash left over. Honestly you could probably pick it up and still have enough for a used Sigma 16mm f/1.4 DC DN Contemporary for Fujifilm X if you hunt for deals. Having that 16mm and 23mm duo would cover basically everything you want to shoot without breaking the bank.

Hey! I've had the Sigma 56mm f/1.4 for years on my Fuji. Tack sharp for street, even wide open. Bulletproof build. Never regretted it, especially for around $480.

Sigma 30mm f/1.4. Consider lens profile correction; barrel distortion exists. Consult pro for firmware update.

Hey! For landscapes/street on a budget, I'd suggest looking at used Sigma primes. Check KEH or MPB. You can often snag a great condition 30mm f/1.4 for around $300, leaving room for a decent UV filter. Be careful to inspect used lenses thoroughly for fungus or scratches before buying! Good luck!

Hey! For street shooting, consider Sigma's 30mm f/1.4. Good choice, but always use a lens hood, especially in bright conditions, to prevent flare and potential eye strain from reflections. Also, are you comfortable changing lenses quickly in busy areas? Maybe a zoom would be safer, less fumbling. Just a thought!

Sigma's great, but consider Tamron. Market research suggests their Fuji lenses are often sharper edge-to-edge for landscapes. Check DXOMARK for comparison; you might save $100.

Consider the Sigma 30mm f/1.4. Easy DIY calibration, but pro setup ensures best results. Happy with mine!