Make a DIY Grid Spot Using a Gutter Adapter and Drinking Straws
Photography enthusiast Jeff Vier made himself a cheap DIY grid spot using a $5 gutter downspout adapter he purchased from Home Depot and a $0.50 bag of drinking straws. Simply cut all the straws to the same length (the longer the straws, the more focused the light), carefully arrange them inside the adapter, and then use super glue to fix them into place. Vier found that his makeshift adapter fit perfectly over his Speedlight 580 EX II without any adjustments.
Image credit: DIY Grid Spot by boingr