Sorry raccoon city, I don’t know what to do about that. Dealing with the whole image hosting fiasco, I’ve pretty much decided to just host from Google (though I’d like to hear if this really is a big problem for a lot of people not seeing the images).
Back to my sphere problem: What first tipped me off to my sphere reading too low on high lumen levels was when I measured my Sofirn SP40, Sofirn SD05 and my Astrolux HL01 (XP-L 4000k). I posted about it over in the SP40 thread, asked for other’s tested levels, and only got one (helpful) response. Basically all three of these lights (at higher levels) gave lumen numbers from my sphere that didn’t make sense. All three lights were measured on fully charged new high-drain cells (LG HG2). As seen in the SP40 thread post, my SP40 on Turbo only came out at 798 lumens. By eye I would have guessed it was putting out at least 1,000 lumens. My SD05 (on a fresh charged new Molicel P42A 21700) on high measured 2,223 lumens and on medium 792 lumens. General consensus on the SD05 (there doesn’t seem to be any authoritative measurements posted) is that it is putting out between 900 and 1,000 lumens in medium (which is a very solid stable regulated level) and +/- 2,500 lumens in high. My HL01 on turbo measured 1,030 lumens at start and 992 lumens at 30 seconds. I was expecting more like 1,200 lumens.
And now that I’ve stumbled on this issue some of my other measurements on other lights at higher lumen levels make more sense to be too low, such as my Convoy M1 XM-L2 driven @ 3.04A only coming out at 840 lumens. I also reviewed that Imalent BG10 XHP50.2 bike light which measured lower than expected at higher levels (which at the time I just thought was the manufacturer fudging #’s).
So in that SP40 thread, YogibearAl measured his 4000k SP40 in his Texas Ace Lumen Tube calibrated with Maukka lights:
Low = 7 Lumens
Med = 65 Lumens
High = 358 Lumens
Turbo = 988 Lumens start up 963 @ 30 sec on freshly charged 30Q. Continues to drop as battery drains.
So I re-ran my lumen calcs based on YogibearAl’s posted #’s above to compute a new multiplier. My previous multiplier was 0.4275, and now calibrating to Yogi’s #’s I am getting varying multipliers, with the #’s for the high outputs being significantly higher (my expectation – that my sphere is “good” at low outputs, but gets exponentially worse at higher levels). Multiplier’s I get:
SP40
Low – 0.4516
Med – 0.4422
High – 0.5000
Turbo – 0.5158
If I then run with the multiplier of 0.5000 from high mode, run that back against my SP40 measurements and also on my SD05 & Astrolux HL01 (XP-L 4000k) measurements, I get:
SP40
Low – 7.8 lumens
Med – 73.5 lumens
High – 358 lumens
Turbo – 934 lumens
SD05
Low – 324 lumens
Med- 926 lumens
High- 2600 lumens
Astrolux HL01
Stepped Ramp Levels:
Step 1 – 15.2 lumens
Step 2 – 51.3 lumens
Step 3 – 145 lumens
Step 4 – 190 lumens
Step 5 – 296 lumens
Step 6 – 472 lumens
Step 7 – 807 lumens
Turbo – 1160 lumens
So now my higher numbers seem more in line with expectations, but I suspect I’m showing lumen #’s that are too high for the lower levels. My sphere was originally calibrated with the average of (3) Fenix HL55 headlamps averaging modes Low, Medium, & High (i.e. dropping Eco & Turbo), where ANSI ratings are Low = 55 lumens, Med = 165 lumens, High = 420 lumens, however I held Selfbuilt’s tested numbers which differed slightly from ANSI: Low = 55, Med = 161, High = 402.
I’ve now finished 4 coats of matte white paint on my new foam sphere halves. I quickly held up one of these halfs to the ceiling light (a standard lightbulb, LED 60 watt equivalent) and the outside of the foam no longer glows like the original sphere, so I think this has helped immensely in keeping light inside the sphere. I’m going to try to test this with a flashlight and luxmeter tonight comparing the lux reading through each foam (unpainted vs. painted). I still don’t have a piece of glass to use, so I’m not ready to assemble the sphere yet.
-Garry