Hmm, kinda late, but I did post this already in the thread before, I guess it was just ignored. 128 is NOT the boundary point for level 5 chests. It's 152. As has been posted, there is some kind of random number that is rolled that is either added to your current lights to determine potency, or is checked against your lights to determine potency. It's difficult to say how it works, there really isn't adequate data to say, but you can definitely roll a level 5 chest even with 0 Azure lights (not sure how many Abyssites this requires, if any,) and it becomes impossible to roll below level 5 at 152 (aside from the ultra rare level 1 fail chest.)
What would be most insightful I think would be to create some kind of box potency distribution with 0 lights. And to also find the other points at which level 1, 2, and 3 chests can no longer be obtained.
Don't know if this has been mentioned or not, and the info on page one has just not been updated.
In terms of Red Chest lights received the hierarchy for at he very least Pearl/Azure/Amber seems to be:
mild: 16 strong:32 intense:64.
Aslo of note it seems as ruby gets higher (until aprox 128 ruby lights) the quality of lights increases while the quantity of lights decreases. Meaning you will see less of each individual light, (due to gold/silver/ebon being added at various tiers) but said lights will often be much higher.
I have noticed the vast majority of my lights being strong and intense in the 90-120 range of ruby, and am 100% confident in this regard. Have been soloing KI's and Items on DNC for the past 2 weeks and have not failed once to build TE's/Ambers using Ruby chests. Personal "Ideal" Numbers have been Ruby 120 (128 will see Azure Pearl Amber mosty disappear from chests it seems) Azure: 148, Amber 140. Pearl of course goes as high as you can get it as i does nothing to determine the type/reward of boxes, only their rate.
Currently working on determining what exactly the effect Ebon may have on lights, early eyeballing has shown me that it does seem to effect light strength from ruby chests (this may be the "effects" all lights thing") as Ive noticed more frequent Intense with higher ebon. However this is hard to confirm as I may have just had a lucky streak against the RNG system for determining light strength. I have a feeling it could play some part but this would require more testing. Will post further findings as I play more with Ebon in the future.
Just got 32 amber from empheral ameoba in miseraux coast. The next one was 16 like normal though
May or may not be known: Pearl lights from VNMs differ. At the highlands, I received 10 pearl from one VNM and at some point received 15 (Was 55 from just VNMs). I'm guess that whatever mechanic affects the Azure/Ruby/Amber from other spike mobs might apply to VNMs as well.