I am thinking about upgrading to a new Sony AX-53 4K cam, but am shocked that it doesn't have much internal memory. And that the BIGGEST SD card you can get is still 512GB. How much will that allow me to film in 4K? And why aren't camcorders putting more internal storage in? Is it quicker with an SD? I asked on the Sony forums, and got yelled at. So please only answer if you can help. Also I'm puzzled as to why all of Sony's 4K traditional camcorders lack a built-in internal light. I shoot closeups in low light settings often; the light is a must. Unless the clarity is so good, they don't need them. But then, the Panasonic 4K Traditional Cam DOES have a light. Any advice would be great. Perhaps I just need to wait until the 4K Cams are more advanced for longer shoots. They seem to be meant for 5-10 minute videos, and I am trying to do 3-4 hours at a time.