Circles of confusion

After posting some of these Christmas pics elsewhere I was asked what I used to get the special bokeh snowflake effects. This is a quick and dirty technique blog on how to create and use a custom bokeh kit.I was going to title it "Custom Bokeh" but last time I did that elsewhere some guy came on telling me it is in fact "circles of confusion" and not "bokeh". For me it will always be bokeh in the background though and C of C is too long winded to use for the rest of this entry so purists switch off now.

So how did I do these? Certainly the stall holder at the German market was curious when I asked if I could take some pictures and proceeded to do so with a camera looking like it had the lens cap on! To the casual observer the set up does look odd.

Camera with filter in place ready for shooting.

 This is my old trusty Nikon D80 with a 50mm 1.8 lens mounted and the snowflake bokeh shaper and the only light entering the camera goes through that snowflake hole in the home made filter covering the whole lens - yes strange isn`t it? Bit like the pin hole camera technology of really. The filter is made by just getting a strip of card long enough to wrap around the lens in a circle shape with another circle cut out to mount on the end of the filter. Some would just cut the required shape out of the end circle but I hit on a way of accommodating multiple shaped filter tools  by cutting a round hole in the end and using a range of shapes attached using velcro.

As you can see I got carried away doing one to fit my 85mm lens as well as my nifty 50 and used a number of shapes using a cheap stencil cutter tool from Hobbycraft. The main thing is that you need a lens offering a wide aperture f1.8 or greater. Sometimes the autofocus might hunt a little with the restricted light so you need to manually focus or get help from your flash if using one that does that focus assist trick for you. My sb800 does it well. As with all good bokeh results the rest depends on getting a suitable subject and the right distance between that and the background to get decent bokeh. A few quick shots to demonstrate trials this afternoon.

No filter in place

Snowflake filter shapes the bokeh or blurred lights / shapes in the background

Why stop at snowflakes - we all love Santa!

Tulips just don`t fit!

Ordinary bokeh

Snowflake filter

These were taken  using Christmas decorations and background Christmas tree lights. Of course you can use natural light or filters on your flash to give differing effects

This one was a tulip (wooden) using dandelions in the background that were shaped with the heart filter.

This rose was taken in front of fairy lights with a red filter on the off camera flash used for a Valentine effort.

Having got the DIY filter out of the cupboard for the first time in a while and slapping it straight on my D700 I remembered that the one I made does not work well with a full frame camera - heavy vignetting but still usable results. I could make another with bigger circles and shapes to allow more light but for the limited use I make of it will maybe just continue to get out my old D80 with it`s cropped sensor when I need it. It`s a plaything rather than a serious tool. Why not have a go and do one yourself if you have the right lenses. Great fun and nothing gives greater pleasure than a DIY item working well for you. Any questions just ask!