>>3389385Ok mate. Look at pic. It's the focus scale on an old lens. Numbers on top show distance, yellow for feet and white for meters. Thicc vertical white line shows you at what distance you're focusing. Colored lines show the depth of field. Depth of field means from where to where the objects in the picture will be more or less in focus. See the colors of the lines match the colors of the numbers? The numbers are the aperture. So when this lens is focused to 4 meters, if you set aperture to f/22 everything from 3 meters to 6 meters and a half will be in focus, if you set it to f/4 stuff from more or less 3.8 to 4.3 will be in focus. Also, an object at 10 meters will be blurry in both cases, but in the case of f/4 it will be much more blurry. Other thing that's useful to know, if a tele lens (say 100mm) and a wide angle (say 18mm) are both focused at the same distance and at the same f stop, the wider lens will have a bigger depth of field (=more stuff in focus). Was that clear enough?
And now please do your own reading, google "how do cameras work" or something like that.
