I've been super happy using my old Nikon glass on the a7C II lately. Like someone mentioned, manual focus is usually the way to go because it just feels more authentic to the glass. I picked up a Fotasy Nikon F to Sony E Lens Mount Adapter for basically nothing and it works well without any weird light leaks or play in the mount. The real hero for me is the IBIS. Since these legacy lenses don't have any built-in stabilization, the a7C II makes them actually usable for handheld shots where they'd usually be a shaky mess. I messed around with the Sony LA-EA5 A-Mount to E-Mount Adapter for some old A-mount stuff and while the AF is okay, it kinda lacks that soul you get from turning the ring yourself. Quick tip: map the focus magnifier to the C1 button. It makes hitting focus with vintage glass way easier than just relying on the peaking. Seriously, dont overthink the expensive adapters unless you absolutely need AF. Simple mechanical ones get the job done for cheap.

Unfortunately, my experience with third-party smart adapters for Sony A-mount glass was not as good as expected. I had constant issues with the camera failing to recognize the lens, which is honestly a huge deal-breaker when you want things to just work. If you want reliability without risking your gear, you basically have to spend more on the official stuff.

• For Sony A-mount lenses, the Sony LA-EA5 A-Mount to E-Mount Adapter is the only one I trust for the a7C II. It is built well, but unfortunately, the AF performance on legacy screw-drive glass still feels a bit clunky compared to native E-mount lenses. It is a bit of a letdown considering the price you pay.
• When it comes to Nikon F glass, I tried a few budget smart options and they were pretty flaky. The Metabones Nikon F to Sony E-Mount T Smart Adapter is way better built, but it is pricey. Cheap ones often have poor tolerances that can actually scratch your mount over time or cause light leaks.
• Manual focus is usually the only way to ensure the camera doesnt glitch out. Using a simple mechanical adapter like the Novoflex Adapter for Nikon F Lens to Sony E-Mount is much more reliable, even if it feels a bit old school. Honestly, the a7C II is too nice a camera to risk with a 20 dollar smart adapter that might short something out.

Adapting vintage lenses, especially Nikon F, on the a7C II can yield unique results. Smart adapters offer autofocus, but performance varies . Manual focus often provides more reliable results and a "vintage feel". For optimal image quality, research reputable adapter brands like those mentioned on Brian Smith's blog (Source 1). Experimentation is key to unlocking the full potential of this combination.