View this image at 100% without any scaling. It is the best test of 4:4:4 vs 4:2:2. Download the image and view it outside browser (this will not work inside browser as scaling destroys the test)
You will be able to read one or the other (4:2:2 at the top or 4:4:4 at the bottom).
You will be able to read one or the other (4:2:2 at the top or 4:4:4 at the bottom).