To add to the point above: jumping in here because I've spent way too many years and way too much money testing every possible combo on these sensors. Honestly, looking back at my old shots, I've tried many different setups and for engagement stuff you really want that separation. In my experience, the micro-contrast you get from higher-end glass is what really sells the shot, not just the bokeh.

• Go with Sigma, you cant go wrong with their glass.
• Sony glass is always a safe bet for the eye-AF performance.
• Stick to the fast primes if you want that creamy look. Over the years I've realized that the specific brand matters less than just committing to a high-quality line. Just get any fast prime from the top-tier lines of those two and youll be set for years... honestly the a7 IV makes almost anything look good tho. Technical specs are one thing, but the way a lens handles flares in natural light is where the magic happens. Thats why I usually dont swap brands once I find a look I like. Feel free to ask if you want more details on how they feel in hand.

Congrats on the a7 IV—honestly, that sensor is basically perfect for portraits. Tbh, before you drop a ton of cash, you gotta think about the focal length first. An 85mm prime is usually the go-to for those creamy backgrounds because of the compression, but I mean... sometimes it can feel a bit tight if you're in a smaller studio space. For engagement stuff, a fast 35mm or 50mm is also a solid alternative if you wanna get more of the environment in the shot. Technically speaking, you should look at the aperture motor type—linear motors are gonna be way quieter and faster for that eye-tracking. Also, pay attention to the bokeh shape in the corners—wait, no, I mean 'bokeh balls' lol. Some glass has more of that 'swirly' look which is cool for natural light but maybe too distracting for corporate headshots. Budget-wise, you can usually find f/1.8 versions of most focal lengths that perform 90% as well as the f/1.4 stuff but weigh half as much. Just my two cents!

> Any recommendations for high-quality options, including budget-friendly choices? Been thinking about this for a bit... you might want to be careful about just looking at the price tag or the aperture specs. I used to think I needed the fastest glass to look professional, but I learned the hard way that a flashy lens isnt worth much if it misses focus during a session. I once spent a fortune on a high-end lens for an engagement shoot and it kept hunting in natural light as the sun went down. It was a total nightmare. I ended up selling it and getting a much simpler setup that was way more reliable. You really have to make sure the autofocus can keep up with your specific body before you commit. I would suggest prioritizing a lens that stays locked on over one that just promises the creamiest bokeh. In my experience, the cheaper options can be surprisingly good, but you have to watch out for things like lens flare or slow motors when you're in the studio. My current setup is actually a lot more affordable than what I started with, and honestly, the reliability gave me way more confidence than the expensive gear ever did. Just be careful not to overbuy for features you wont actually use day-to-day.