You can either purchase one that is specifically made for built-in flashes or you can make your own from materials you can find around the house.
The diffuser shown in this instructable is great for diffusing and directing the flash to a specific area. I mainly use it pointed upwards so that it reflects the light off the (white) ceiling and onto the subject. You can aim it in any direction by angling it or making the hole in a different part of the cup.
Step 1: Materials
- Aluminum Foil
- Scotch tape
- Double-sided tape
- Styrofoam cup
- Pair of scissors
Step 2: Cut Off the Bottom of the Cup
Step 3: Line the Inside of the Cup With Aluminum Foil
Use small peices of double-sided tape to held the foil in place.
Step 4: Tape Off the Aluminum Foil at Both Ends
Step 5: Dealing With Leaks/rips
Step 6: Sample Photos
Note: These pictures were taken in a dark room without any other lights.
Step 7: Other Configurations
You can also cover the outside of the cup with a black material to make it look more appealing.
If you'd like to allow some light through but would still like most of it to be directed elsewhere then you can keep some parts of the cup uncovered by the aluminum foil.
Using different sized cups yields different results so make sure to experiment with it.