What do you do when auto-focus fails? well, there are two ways auto focus can fail, either it focuses on the wrong thing or it doesn’t manage to focus on anything at all, we talked about what to do when auto-focus locks on the wrong subject last week, today we will talk about what to do when the camera can’t auto-focus at all.
There are 3 common reasons for auto focus failure:
- You are too close – each lens has a “minimum focusing distance” and it’s just can’t focus light from something closer (for interchangeable lenses cameras that distance is usually printed on the bottom of the lens) – if you are using a point and shot camera you can go into “macro” mode (that usually has a flower icon) for camera’s with interchangeable lenses you need to switch to a macro lens, move back or read next week’s post about how to take macro pictures with no extra equipment.
- You are pointing you camera at something that is just a flat color – the camera need something to look at, if you point your camera at an evenly lit single color wall (for example) it can’t find focus because the in focus picture looks the same as the out of focus picture – in this case you can hold something next to the surface you are photographing, focus and then remove the object and take the picture.
- The third and most common case is not enough light – the camera is not as sensitive as our eyes (at least when auto-focusing) and can’t focus on something it can’t see – in this case a simple flashlight can help (light the subject, focus, turn off the light and take the picture) but sometimes that’s just not possible and you have to focus manually.
Some people can just look trough the viewfinder and set perfect manual focus every time, I’m not one of those people – so what do people like us that don’t have perfect eyesight can do?
Turn on live view, use the live view zoom function to zoom all the way in and turn the focus ring until the zoomed in picture is sharp – it’s that easy.
It’s easier to do this if the camera is on a tripod and the subject is not moving, but if we are in low light condition than you need a tripod and a stationary subject anyway.
That’s it, this was a shorter tip than usual, next week, as I said before we will talk about cheap macro photography.