I agree. I have previously posted on this confusion. The arithmetic scale of the LED graph completely hides from casual view the fact that photographic materials are sensitive at low light levels (thank heavens!) and if you draw that graph with a log vertical scale you will see heaps of overlap with the paper sensitivity.
Originally Posted by PeterB
Try looking at the LED by reflecting the light from the base of a CD at the angle that gives the "rainbow effect" to give some idea of the spread of colours. I tried it with some amber LEDs about which I had high hopes, and found not only yellow but aqua! Needless to say, they fogged until I placed a sheet of Rubylith over them.
Incidentally, those LEDs I had chosen because they had a narrower spread than most, according to their specs.