Make Your Own Bokeh Effects Filter for a DSLR

Even if you’re a casual photographer, you might be familiar with the term ‘bokeh’ — the artistic use of out-of-focus backlight to surround your subject. When done correctly, you can create a gorgeous professional image that really pops off the page (or screen). We’ll show you how to customize the shape and style of your bokeh with your very own makeshift bokeh filter.

For this DIY to be useful, you’ll need to already have on hand some specific equipment. Most notably a DSLR fitted with an appropriate lens for producing the bokeh effect — a 50mm lens with a low f-stop works nicely. For this tutorial we are using our own Sigma 50mm f1.4.

Supplies:

• A few sheets of black construction paper or posterboard at least 11×17″(medium thickness) – easy to cut, but rigid enough to not tear easily
  
• X-acto knife
  
• Scissors
  
• Electrical Tape
  
• Velcro

Got everything? Good. Let’s make it happen…

To start, we’re basically going to make a circular cutout that will fit over the top of your lens. The cutout needs to be a little larger than the lens so it can easily fit over it. The cutout will also have a small 3/4″ diameter hole in the middle — this serves as our base filter. We’ll fit interchangeable cutouts, in any custom shape we want, over the base filter to create the effects. In this step by step, we’re going to outline the process by hand, but you could draw the templates in Photoshop as well.

1. Draw a circular template wide enough to fit over the front of your lens. An easy way to do this is lie the lens — lens-side down and with lenscap on — on the paper. Get a pencil or pen and trace around the lens with the pen abutting the side of the lens.
2. Using a T-square or ruler find the center of that template by drawing a cross-hair
   
3. Make marks 3/8″ from the center of the template. Then connect the marks to create a 3/4″ circle.
4. Cut out the template and the 3/4″ hole in the middle.
   
5. Now you’ll need to make the side of the lens filter. Calculate the circumference of your lens: remember pi (3.14) * diameter? Take that number and add a 1/2″ or so (for overlap) — this will be the length of your strip.
6. Take the front part of your lens filter and wrap the rectangular strip around it. Attach the two elements together with some tape for a secure fit.
   
7. Add two velcro strips on top and bottom of the center hole — we used velcro tabs and cut them in half. Your bokeh filter is done, and now its time to make some custom shapes.
   
8. We’ll make some interchangeable filters by cutting out some more circles from our template paper. Let’s make one by simply cutting out a circle that is a bit smaller than your lens filter but larger than the 3/4″ hole – a drinking glass usually works well as a guide.
   
9. Now find that center point and cut out whatever shape you want your bokeh to take. Just try to keep the total width within about a 1/2″.

Want something more interesting and intricate? Then try gathering unique 1/2″ or 5/8″ paper punches at your hobby store or online. The 1stopsquare site seems to have lots of fun shapes you could use.

After that shape is cut, just attach opposing velcro strips to the top and bottom of the filter and attach to the lens filter you just made. Ta-da!

Now you can make several interchangeable filters and swap them out on the fly. The filter works best at night when focusing on something very close, with bright scattered light in the background — think christmas lights. Here’s some more shots we took with it.

Hope you enjoy this easy, cheap, and fun DIY. Let us know what shapes you make with it.