I'm using a 150W near infra red bulb and haven\t seen any results after hundreds of hours of use. Perhaps it's not powerful enough?
The only thing with these bulbs is the heat and not knowing the nanometer of the spectrum...
I was thinking of trying this based on the study: Intsun 96 Leds IR Illuminators Light IR Infrared Light LED infrared light CCTV Camera Night-vision Fill Light for CCTV Security Camera, Standard 45° Level Angle Visual Range (96 LED): Amazon.co.uk: Lighting
It looks cheap. Check the wattage to understand why (15W).
I've been using a 400W halogen spotlight. Seems to work great for me.
I did 2500W halogen by combining several. I got more freckles which confirmed UV was coming through, so I sold all my halogens.