Ok everyone. Good news, the lights from maukka showed up! Huge thanks to maukka for these!
So after testing them along with some other lights the numbers are lining up very well.
Like most I found .68 is the magic number.
So now to correct the spheres. I spent most of the morning looking at options and trying to get this to work in the simplest method possible. Including going to window tinting shops and getting some samples.
After a lot of testing I think I found a method that should work, I still need to test it on several more but the random sampling of 5 spheres I have been using are working well with it.
Even after sitting for awhile and being moved around several times and having these correction disks added they are all reading within my 5% goal (although 1 of them was right on the edge). I think I am going to raise the official specs to +/- 7% tolerance simply because I am sure there is an outlier that falls in that range and that is the Cree tolerance range anyways so why pretend that these can be more accurate then cree.
So the setup I am working with now are 2 of the diffusing sheets I used inside the sphere.
Depending which way they are orientated they can have a correction factor of .70 or around.66. So either 2% high or 2% low.
I think I am going to recommend going with the .70 correction factor and then simply rounding down your numbers since I recommend rounding them off anyways.
Plus I find that my sphere tends to drift a bit low every few weeks just due to dust and such. So that should balance out the readings to make them basically spot on since these will get dirty no matter how hard you try to not let them.
I am still going to try some other things but so far this is the closest I can get without having to stack 4-6 layers in just the right order and orientation of various materials. That is simply too much room for error for my tastes. Even how clean/dirty the disks are plays a noticeable role in the results.
The opaque diffusing sheet gets it really close with a single sheet but it is still around .65~~.66 one direction or .70~~.71 the other. It is simpler but slightly worse off.
Plus by sending everyone 2 of these sheets the spheres could be dialed in a bit better on a per sphere basis if a good “standard” light is ever made for individual calibration.
So opinions, how does everyone feel about a .70 correction factor?
Would you prefer .66?
Should I keep searching and find a .68 correction factor even if it is much more complicated leaving room for error?
If everyone agrees on a .70 correction factor I can get another diffusing sheet and get it laser cut this week and have it shipping out by next week.
Personally in my own sphere I will be using .70, it is good enough for me. I generally find that the simplest option is the best option. Plus since I round down anyways the numbers should be good.
Thanks for everyone having the patience to wait for a fix.