djozz… what hardware did you use to get that tint reading in your test? It looks interesting.
A Gossen Mavospec Base, which is a handheld spectrometer targeted to the professional lighting market (but is bought every now and then by a hobby freak). There is similar devices around by Sekonic and other brands.
Cool… yeah I was hoping it was something much less expensive. 
I've read elsewhere that brass screws can be purchased for the Q8, and will also help get you a bit more brightness. I would definitely recommend XPL-HI or XP-L2 over the stock XP-L.
Oh man the DUV is very disappointing. I was hoping it will be -.008 DUV with bare LED so even with optics, it would still not be green.
BTW, I’ve been considering buy a spectrometer for a long while but haven’t yet because of the price. Maybe in the future I will. Why did you choose the Gossen Mavospec Base over Sekonic or any other brands? How does yours compare with Maukka’s spectrometer?
I’m not sure how maukka’s measuring setup is done, it is not a handheld spectrometer like mine but works via a computer, and possibly an optical fiber is used to collect the light.
And I did not do an extensive search for the best, cheapest or most versatile spectrometer (the Sekonic C700 is cheaper and more versatile, not sure about quality and accuracy, should be ok too), the Gossen spectrometer was recommended and sold to me by a dutch lighting company that also very friendly helped me with calibrating my luxmeter last year. Call me lured into this one 
Handheld seems more versatile since you can measure any light source including ceiling light fixtures. I will look into the Sekonic. I also want it to have decent spectrum reader so I canuse it to help me minimize blue wavelength lighting in my bedroom. The E21A 2500k with majority red wavelengths seems to really put me to sleep compared with other lights Ive used at bedtime
Maukka uses something like this I believe:
See this thread:
Doesn’t seem much different than what djozz uses
You can find guides online to build a Do-It-Yourself spectrometer. It’s similar complexity to DIY lumen tubes.
Here’s some basic spectral analysis software designed to work with DIY spectrometer:
I don’t know if any of the Spectral Workbench contributors have developed a package to produce chromaticity diagrams or calculate CRI.
I want to ask if there is a ~eta on the springs? Last thing i read was that theay are ordered. But i did not read all the thread.
I think it’s expected to take the slow boat. So probably several weeks. I may be remembering wrong though. Maybe BlueSwordM will step in and answer.
EDIT: I was curious myself, so I looked back at the first spring order. Blue made the order and sent payment by 7-07 and had the springs in his possession by 7-30. That’s 23 days.
Yep. It takes quite a long time, especially since the springs have to be manufactured all at once this time.
Once I have any news about them, I’ll post about it.
Shipping itself is very fast, but making the springs and electroplating them takes more time, as I’ve discovered that they don’t do silver plating on site, unlike nickel and tin.
Sorry if it took a bit more time, but the springs ready, and prepared to ship from the manufacturer.
They all look very nice.
Lookn good. Thanks for the update
Whoa, bling!
BlueSwordM you must have the patience of a saint to untangle all those springs.
Yeah, it takes a bit of time.
However, one way to untangle them all is just to mix them in the bag, then put them in another bag.
Actually works pretty well.
Those look great! :+1: … Looks like the “fun” begins pretty soon for you…… having to sort that tangle out.
This, I have the 2000K E21A, more like 2300K in person, and I feel naturally sleepy with it on for a little while.
Related followup to my earlier post (follow along in maukka’s thread for discussion so we dont derail this one too much)
I ended up buying the cheapest spectrophotometer X-Rite makes (ColorMunki Photo / i1Studio) for $250 used but good condition on ebay. With just that investment I am able to get all the spectrum data needed for CCT/CRI/DUV and can make wavelength and CIE plots with entirely free software.
While it isn’t a self contained mobile device like what djozz has you can buy a $2 OTG cable and a $99 app that will get you “mobile” if you don’t want to use a laptop.
After having done this now I really wish we could do a BLF Arduino/Pi based spectrophotometer and lux meter. It doesn’t seem that complicated, the device outputs a decimal value for each wavelength and that’s it. The rest is just math equations using those numbers to get the rest. No special sauce/proprietary stuff needed.