Here are some tests with spectrum results
Lots of lights and leds tested by awesome members. Im going to point out maukka’s tests as they have consistent spectral measurememts
blue cross represent spectra that I currently possess(measured or mixed, and some from internet), the orange part is from SDL strip that I mentioned before, notice the two rear parts, seems the two extreme rear ends are statistical outliers(SDL strip’s dimming range is 1800K~12000K, this quite low and high CCTs may correspond to this graph, and in the long run, SDL would support 20000K and even higher CCTS).
I don’t have flashlights spectra, but I think flashlights spectra may show a little common characteristics with this SDL spectra, that is their spectra are kind of statistically different with those spectra that I currently have. actually I want to classify different spectra and then handle each kind of spectra specifically(divide and conquer should generate more accurate results). but I can’t as shown in the graph, SDL spectra overlap with “average / normal” spectra.
btw, the lens may incur shift in spectrum, maybe lens of flashlights differ a lot from home lights which are made of materials like PP or some other plastics.
in a word, if spectra from flashlights and home lights are statistically conform to same distribution, there ought to be no precision difference between them. but there does exist some difference, why?
You mean tint shift? If there’s a diffraction, any optics will bring it out. Is this a problem? A true spectrophotometer will also not measure the LED, but LED plus optics.
Flashlight-use optics are very even transmittance through entire visible spectrum, usually made of glass, polycarbonate, or PMMA, should not cause that issue.
I’m not aware of any earthly material that can visibly shift an entire spectrum. You’d need a very fast moving flashlingt for something like a redshift. For some wavelengths, there could be fluorescence due to impurities of the material. But you wouldn’t been able to measure this with the Lightmaster.
Please correct me if I’m wrong, but absorbing and emitting photons seems to me the only way to alter the frequency except special and general relativity. A very massive flashlight (carved from a neutron star) might indeed have an effect, too. But you shouldn’t handle those anyway.
Hi guys I have an Opple Lightmaster 3 and I need a spectometer analyzer for all visible spectrum (Lights. Led lamps, Red therapy) and I’d like a score as in this picture
IIRC that isn’t because of the material itself, it is because of the optical properties changing where on the emitter the light comes from. The same effect happens with PMMA TIRs and probably glass too, though I don’t have any to try it with.
No, you cannot use any of those Lightmasters for this. The spectral resolution is far too low. The LM3 has six, the LM4 eight wavelengths in the visible spectrum.
Hi guys, I got a flashlight, seems its LED chip is quite low-end because its Ra is 73.7, I measured it using integrating sphere.
but I found one weird thing, LM3’s reading is 75.9, and LM4’s reading is 80.8, when I shine the flashlight directly at LM4, LM4’s reading is 96.8. LM3 works OK under this scenario, why?
I compared this spectrum with other Led spectra, yes Led’s spectra are quite alike from human’s eye. but seems green&red part are much more “fat/convex” than other spectra. in a word, it is not i.i.d from distribution of spectra that I have(independent and identically distributed). perhaps when I add spectrum to my spectra database, there will be improvements.
I think inherently there are shortcomings with 6 or 8 channels sensors, quite few. integrating sphere got 401 data points, IS is like vernier caliper, but I got a meter ruler.
