13th December 2017 – The Xmas Do and a bit of Bokeh

Blog has been on a bit of a hiatus through other commitments but hopefully is back to being regular now. Our last session was the club Christmas party and a good time and a few quid raised for club coffers means that it was a success. A record was probably set for unflattering-photographs-of-club-members-whilst-sober  but it was all in a good cause. Our thanks to Myk for running a very enjoyable evening.


The programme in the new year is full of promise too, underpinning the aim of the club to be one where we learn together rather than one where blokes (it always is blokes) stand around, sucking the air through clenched teeth, fiddling with the string in their cardigan pockets whilst moaning about things not being as they used to be in the good old days.


Like any skill we learn as much, arguably more, by not getting it quite right and keeping a balanced and critical eye. Use the judges’ opinions and try them out. Critique the result for yourself and compare it to your original. Use the clubs internal online presence (sorry members only) to try  out others opinions. Use a buddy group, use external sites that offer critiques (thick skin sometimes required). There are lots of options.


Try something new. Christmas is rapidly becoming the one time in the year many photographers decide to try out bokeh. Everything to do with the Christmas Tree lights. Bokeh is an example of making the most out of something you can’t change. In this case, the laws of physics, branch optics.


If you look at the world through your camera phone, most of it is in focus most of the time, even though the lens aperture is usually pretty wide. Think of the situations cameras are used in phones for the most part and keeping things still enough not to blur means a wide aperture is a good idea to keep shutter speeds up. This is because of the depth of field relative to the size of the sensor you are using for capture. Basically F2 on your camera phone is roughly F11 on a full frame (35mm) sensor in terms of depth of field and camera phones use wide angle lenses (compare further). Note that is not an expression of the amount of light transmitted, only the area we find acceptably sharp.  It also means, practically, that, mostly, bokeh effects on camera phones are software rather than optically driven. This is by the by for most users.


You can, at least in theory, construct bokeh on any lens (tougher on a fish eye, but possible). The term bokeh is Japanese and an art term for the aesthetic qualities of out of focus light. It can also, given the right context mean senility or mental fuzziness, apparently, but that too is by the by.  The keys to successfully taking a bokeh photograph are pretty straight forward. Paying attention to the basics of composition is as important as always. The effect may be out of focus but the subject must be in focus. Maybe obvious, maybe not, but essential nonetheless. Get as close to your subject as possible, framing is important and only having one subject is as important as ever it is.


The largest aperture on your chosen lens is also a given if you want to  maximise the effect. Prime lenses are probably better than zooms as they tend to have larger maximum apertures. F2 is more convenient for this than F3.5 which is better than f5.6 in that the depth of field is less for any given sensor size the wider the aperture set at a fixed focal length. But as with everything kit wise the one you’ve got is the best for the job.


The other key is the separation between background and subject (and, of course, having some light in the background!). The larger this gap is the larger the bokeh effect will be. Of course the Christmas tree isn’t likely to have a lot of room behind, nonetheless the effect is still obtainable, though colour balance can be tricky. If you are at macro distances then the effect on the background can still be striking, though of course through a more restricted field of view. That includes the use of lenses and extension tubes, just bear in mind depth of field is extremely shallow.


The shape of the bokeh is determined by the number of leaves that go up to making the iris. Cheaper lenses tend towards having five or six blades to the iris, more expensive lenses 9 or more (and in between). The more blades the more circular the bokeh appears. The other factor is the placement of the blades, straight or rounded making for hard edged or circular smooth points. You pays your money and you takes your choice.


And that is pretty much all there is to it. It can be done indoors and out. It can be done in different light levels. It’s a simple technique that makes the most of a physical necessity. It can be one point or many depending on light source(s). Straight forward and quite striking. Try it.


Happy Christmas.