Juhani says: October 26, 2015 at 3:28 am The issue is that you must get all the light to 1cm x 1cm spot. I've 100W led (8k lm) but I get more light to monitor from one 1k lm Cree XM-L2. Next issue would be the narrow wavelength sample of https://epson-projector-bulb-near89888.kylieblog.com/37330100/epson-projector-bulb-hours-fundamentals-explained