I have and still own various cameras. I use different cameras for different things. But I have a favorite. One that is my go to carry it with me everyday. I like the results I get from it SOOC, I love the color, I like the way it works, and I like the way it feels and handles. And it has one hot pixel. Arrrrrgggggg. 😡 But it is still my favorite camera.

So this post is not about what camera is best or most expensive or mine is better than yours, or DSLR vs Mirrorless, or brand loyalty. It's about what camera is your favorite camera, and lens, and why.

Mine is my Olympus OM-D EM5 Mii + 14-45 Panasonic Lens.

What is yours?

I will probably start a range war here, but, I think the phrase "I don't like my camera making decisions for me" is so overused. I contend, unless you are shooting creatively, the camera is, in fact, making decisions for you. The purists always say, I shoot manual mode because I want to be in control of my camera. So, you set shutter speed, you set the aperture, you set the iso, but then, you check the exposure meter. If the little slider line is not in the middle (for proper exposure), you then adjust one or more of the three (shutter speed, aperture, iso) To get WHAT THE CAMERA SAYS is proper exposure. So, as I said, unless you are shooting for creative effects, and ignore the exposure meter on your camera, that camera is making decisions for you. What say you?

I have the Nikon Df which has very low noise. When I was shopping for it the dealer didn't have it and the sales guy tried to sell me the D800 and said if you down size the image from the D800 to 16MP you would have the same low noise level as the Df. Plus you have higher resolution when shooting in bright light and noise is not a problem.
Still I didn't buy the D800.
So what I said to the OP is that he could down size the image from the A7RIV when he has to shoot in low light and have the same resolution as the A9 and possibly same noise level. In bright light he can have the 61MP images.