While making the Softbox, I used some of the smaller scraps and made a snoot that I’d been wanting to try out for a little while.
The first shot shows all the materials involved: straws, scrap corruplast, and some duct tape. What it doesn’t show is that the straws are taped together. The next shot is with the straws extended slightly.
The next shot shows the flash firing without the straws inside it, and then with them. As you can see the beam is significantly tighter. It’s also a bit dimmer. You’ll have to raise the flash power to compensate. I’ll update this post with a more exact value of how much light you lose.