Texas_Ace BLF Calibrated Lumen tube / Sphere No math skills needed - Several spheres still available

[quote] Very interesting. What were the readings on both lights without the discs at all? [/quote]

Let's see, from page 12 of this thread;

and from page 21 of this thread

Just making sure if I am installing it correctly… is this correct? Rough disc is not touching the sensor. Thanks

I just received three correction discs. The instruction says to use two. I just want to make sure for the 4”, I should use 2 also right?

Yes two… smooth disc is suppose to touch sensor right??

Good info Terry Oregon, thank you…… :+1:

If things seem off when I get mine, I’ll sure give this a try.

Thanks for looking that up. Very strange, it seems to be giving a lower correction factor then it should but it seems to be inline with the numbers I got with the old sheets in that orientation (around .64)

It is unlikely but possible that he managed to get 2 of the first batch of discs that read a little lower. In which case he is correct, flipping them around is what is needed to get the correct readings.

Yep, that is the correct way to install them physically, although I can’t tell which orientation they are. Both of the smooth sides should face towards the inside of the sphere with the new discs (which I made 100 of). With the old discs they were the other direction but there were only about a dozen of them mixed in, so it is unlikely that most of you have those.

Yep, I sent 3 to everyone (and 4 to the international people) just in case 1 broke in shipment. Easier and cheaper to send a spare then ship another package. I had the buy the whole sheet of diffuser anyways.

You only need to install 2 of them though.

I am not sure what you mean by smooth disc? There should be a smooth side and a rough side to each disc.

You want the smooth side to face towards the inside of the sphere for both discs in most cases (unless you got one of the first batch of discs).

this is what i’m experiencing with my kit.
With both smooth side facing the tube i’m getting a .64 correction. it seems a little low.
what seems to work for me is the smooth side touching, with that i’m getting a .675 correction.

I got different results…

Smooth disc facing the tube = lower reading
Rough disc facing the tube= within range…

I think my set up is same as your…

Are they subtlety marked in any way or is there any way to tell the difference between the “first batch disks” & the ‘new disks’??

Do you have the rough side of both disc facing the tube?
I did try it that way. I think the correction factor was around .74
The way I have mine setup is the rough side facing the tube and the sensor.

Hey krash, here is the photo… its the rough side the picture you see…

Wow. I tested my pelican 7060, 368 lumen light… it was right on the spot… 369/368/366. By the time I took a pic, it was 366 lumen…

I also tested the fenix tk15 and it was around 1045 lumen around 20 seconds range…

So far so good…


free upload pictures

Is that a 4” sphere? That could be why we are getting different results.

Is there a difference in readings if you align the two discs with each other with regard to the ridges on them or if they are at some random oblique angle?

I used an S2+ short tube with aspire 18350’s - medium mode, fresh battery each run, two runs each configuration, measured beyond 30seconds and got:

No disks - 503

2 disks smooth side in - 313 (.62)

2 disks smooth side out - 370 (.73)

2 disks rough side facing each other - 342 (.68)

I’m going to use the last configuration - seems good to me.

It seems clear to me that we should use a stable test light and then experiment with the discs until we get as close to a 0.68 correction factor as possible.

Let’s say it reads 1000 lumen before then we want it to read 680 lumen with the discs.

500 before
340 after, etc…

Please don’t try and make a light match it’s rated specs. That is not the point of all this. :wink:

Yeap… . I dont even try to match… TA said two rough disc should be facing the tube… thats what i did, and results are great…