For my helmet light, I was using a Zebra Light H602W (Flood, Neutral Color). It's good for close, smaller space video work. It's small and runs on (1) 18650. Apex Headlamps are pretty popular for caving. If you want to spend the coin, StenLights are also popular. If I need to bump up the light, I pull out my FF4. I made is diffuser for it by buying a Filter and then using a glass etcher to frost it. If I need more light, then I pull out by Barn Burner (my favorite light) or a homemade 100W Ballast HID Flashlight. Technically, I can pack in lighting to generate about 55,000 lumens, but I need folks to help carry my gear. Living in SC, you could drive to TN....they have some large caves. Thanks for the comments.