Don’t you just love that ‘bokeh’ blurry background effect that photographers get? I do, not all the time, but used appropriately, it can create really memorable images.
How do photographers create this blurred background thing? Quite simple really – it’s all down to having a very shallow depth of field, which is probably easier to understand if you call it ‘depth of focus’. For example, not using real figures: with a certain lens at a certain focal length – that’s the millimetres thing, you know, 28mm, and with a big hole, better known as an ‘aperture’ or ‘f-stop’, say f2.8, only the thing you focus on is in focus, plus a very shallow area behind the thing you focus on. Say, 1.5 metres. This means that anything beyond 1.5 metres, is not in focus. Hey presto! Bokeh!
Stop reading, start speaking
Stop translating in your head and start speaking Italian for real with the only audio course that prompt you to speak.
The trouble is that this depth of focus changes in relation to the length of a lens and the size of the aperture. Smaller apertures, that’s with bigger f numbers (f10, f18, f32 etc) have much deeper focus areas.
This depth of field or focus thing, as you prefer, can be calculated – just search Google for ‘DOF calculators’, and there are even charts to help you. But we live in the digital age now, so why can’t the manufacturers build a DOF display into their cameras? Much better than that silly ‘direct print’ button thing on Canon dSLRs, or so I think.
Just a photographic thought for the day, inspired by this photo, and, if you click, you will see a comment of mine on this very subject.
