How to choose a full-frame camera
Start with the split between resolution and speed. The Sony a7 IV’s 33 megapixels give you real cropping room and detail for large prints, which suits a photographer who shoots portraits, weddings and travel and edits heavily. The Canon R6 Mark II and Sony a7 III sit at 24 megapixels, which is plenty for almost everything and actually helps in low light — fewer, larger pixels gather more light per photosite. If you print billboards or crop aggressively, lean toward more resolution; otherwise 24 megapixels is the smarter, cleaner default.
Then weigh video. This is where the Canon R6 Mark II pulls ahead: it shoots uncropped 4K60, so you keep your full field of view at the higher frame rate, where the Sony a7 IV drops to a Super 35 crop for 4K60. If you film as much as you photograph, that difference is the whole decision. For stills-first shooters who film occasionally, both Sony bodies are more than capable and the crop rarely comes up.
Finally, think about the system, because the body you buy commits you to a lens mount for years. Sony’s E-mount has the deepest, most affordable lens catalog of any full-frame system, with huge third-party support from Sigma and Tamron — a real advantage as you build a kit. Canon’s RF mount has superb first-party glass but tighter third-party options. Whichever you choose, remember that a good lens changes your images far more than the body does: our portrait lens guide and video lens guide are where the real image-quality upgrades live.
Do you actually need full-frame?
Most people don’t, and we’d be doing you a disservice not to say it. A modern APS-C body like the Fujifilm X-S20 or Sony a6700 gives you excellent photos, clean 4K and a viewfinder in a smaller, lighter, far cheaper package — and the money you save on the body and its smaller lenses buys better glass, which matters more. Full-frame makes sense when low-light performance and shallow depth of field are genuinely part of your paid work, or when you already own full-frame lenses. If that’s not you, spend less and shoot more: start with our hybrid camera guide or the beginner mirrorless picks instead. And whatever body you land on, the biggest upgrades to your results are almost never the sensor: a fast prime, a good microphone for video, and time spent learning the light beat a bigger sensor every time.