How to Make a Large Flash Diffuser

Author: | Posted in Projects No comments

Making nice photographs when all you have for lighting is a bunch of tungsten shop lamps can be a real challenge.  It is particularly hard to photograph polished brass under these conditions.  So this weekend I set out to build a flash diffuser to improve the quality of the photography on this site.

Most of the diffuser is made with foam board and packing tape.  I laid out a square 30" inches on a side and then drew a cut line from each corner to the center of the top line.  This gave me two right triangles that when taped together matched the center triangle.

I cut two sheets of foam board in this manner.

cutting foam board

When all of the pieces where taped together I had a square "horn" shape.  I used heavy gage steel wire to stiffen the front-most edge.  This wire is from a political sign of the sort that people put in their front yards.

 These signs are also a great source for small to medium sizes pieces of coro-plast.

tape foam board  wire re-inforce foam board

Next I taped a piece of acetate about halfway up the "horn" and I built a support from two pieces of wood and some more foam board which I glued in place with carpenters glue.

flash diffuserflash back

The flash is mounted with Velcro and triggered by a Wein Peanut Slave.

slave flash mounted


A 1/4" x 20 capture nut was installed in the bottom to allow the diffuser to be mounted to a tri-pod and I used gaffer tape to secure a 30" x30" piece of acetate over the entire front of the diffuser.

slave flash on tripod  firing slave flash

The light is very even.

flash front

Here's my first test.

diffuser flash on work bench  airship telegraph

This photograph was taken with the soft flash diffuser at a 45 degree angle directly above the table

sexy shot

This photo was taken with the diffuser about 4 feet in front of me, right next to the camera.  The camera is a Canon Powershot S3 set to full manual – 1/500, f8.

I am very happy with the results, total cost of the project was about $10 and the quality of the photographs I can take for this site should improve immensely.

Jake von Slatt