I've owned and shot many a photo using manual and AF camera, 35mm, digital and Med Format but although I use hyperfocal focusing when I can, I can't say that I've ever used infinity focus.
I know I used to know this but years of not bothering with it has made me forget. On the distance scale of my lenses I will see a number of distances and then a longer throw and the infinity symbol. Does that mean that anything from the last distance marked is included in infinity? Evidently not as when I focus on an object past that marking the lens is not focused at infinity. Infact often when focusing far beyond the markings with an AF lens, such as 100m away or further, the lens still doesn't show infinity on the distance scale. Then it seems that it is possible to rotate the focus ring past the infinity mark on the scale.
As I thought I had understood it, infinity focus is a certain distance from which anything further will be in focus, at any aperture. Is this the case that if I set the dial to the infinity mark? How do I know what distance the inifinity mark is from, why can I focus further than the infinity mark?
I'm rather embarressed asking this, I'm a pro wedding photographer and I dabble in landscape photography for recreation. I know hyperfocal focusing, I know zone focusing and use both in day to day shooting but I realised that although most of my photos would not warrant or make use of it, I should remind myself of what Infinity focus is useful for.