Bill, I found almost an identical experience to that described by Ken with bright orange LEDs. I did the same test with a CD, got green and blue spikes. I tested both a Lee lighting gel 19, fire orange, and a Lee primary red. Orange was safe to just 4 min, while red gives me 15 min safety with MGIV WT. Michael 1974 has been very helpful by sharing his filter experiences when he was building his LED safelight. I am delighted with mine now.