Interesting. Yet another example where medical equipment has been slow to adopt technology that has been around in other areas for quite a while! smile

Have you tried other (cheaper) light meters, compared readings with the "official tester", and applied a "fiddle factor"?

I haven't checked the relative fluorescent versus LED wavelengths. Why not? ... too busy ... I'll give someone else their chance (but this guy could tell us), but it could be a 1:1 relationship (or near enough) for all I know.

Meanwhile, there are some nice ones here.

If you don't inspect ... don't expect.