| L0 | 0.958 | incandescent |
| L1 | 0.851 | LED white |
| L2 | 0.902 | LED amber/yellow |
| L3 | 0.772 | LED green |
| L4 | 1.642 | LED red |
| L5 | 1.475 | LED blue |
| L6 | 1.148 | "Not used" |
| L7 | 0.484 | my custom bobbersphere setting |
I have the LT45 too and when I look at my settings I get the above. L7 is set to my own factor based on a calibration light and diffusion I used in my bobbersphere.
If a red LED is approx 1.93x a normal daylight white LED (0.851 * 1.93 = 1.642) cant we multiply our integrated values by 1.93 to get "red lumens"?
I suspect you could gut check this with the datasheet of a red LED.
Also here is the meter sensitivity by wavelength:
I guess if we say LED peak is around 580-610 and red LED is 620-660 it seems reasonable? I'd bet the 1.93 is more for standard red and photo red would be even higher than 2x to be honest.