The Legendary BLF Integrating Sphere starts here! (Delivered)

Sounds nice! I guess to europe would make it about $70, wich is quite expensive…
Maybe resourcing the parts locally and just shipping the 3D printed parts would be an option? Or can’t you calibrate it that way?

Won’t these styrofoam spheres melt on some of the more powerful mods seen on BLF?

Well to get a universal calibration you need the EXACT color sphere it was designed for. Preferably from the exact same batch. So if shipping from the US is not acceptable, I don’t think we would want to think of it as the standardized one. To avoid mass confusion that could destroy trust in the sphere, I would not share the 3D printed parts, sorry. That will be the unique identifier of the standard ones.
It’s not at risk of melting because the readings are instant. No need to keep the light on after you look at the display.

I’m on the fence about melting becasue of lack of data but i would still calibrate any sphere, all precision equipment requires calibration because production tolerances and variations exist in any manufactured product. Calibration is a big business and quite expensive.
Also you would want more then instantaneous readings, the ANSI standards are after 30 secs of continuous operation, and i imagine may BLFers would want to know how long a battery lasts before brightness decreases from voltage sag on a battery.

Alright, 30 seconds it is. I will put a plastic insert/platform in that hole to ensure Styrofoam never touches your flashlight.

And yes, I plan to do a deviation test on each one. There will be an place on the app to plug in your scale factor! Cool ey?

15cm Styrofoam…probably too small?

Well, design changes are up for discussion. But I believe small is good for more accurate readings.

If I could see a production version, and there was some testing done I’d be willing to get on board.

It’s my understanding that sphere size should relate to the lens diameter of the light, ie small lens, small sphere; large lens, large sphere. I’ve read a number of posts here regarding one light giving somewhat different readings in different sized spheres which were both calibrated to one source.

But anyway I’d be interested in a standard ‘BLF’ sphere at that price level. Just no time to make one for myself.

Phil

I would want it to last an hour or two so you can track brightness over time, and lumen sag based on heatup of the head takes longer then 30 seconds and on various modes as well, knowing how long low mode lasts is very useful for an emergency situation light. Fortunately lower modes should have a lot less heat.

Also there is a light reflective coating used in many spheres, i forget what its called but has been mentioned a few times.

Actually large is better to minimize small artifacts instead of magnifying them. Real integrating spheres i have seen photos of are huge, you could fit people in them (if very uncomfortably).

Well I own and operate an electronics manufacturing company with a multi-state dealer network and very happy customers. So don’t worry about my skills.

Sounds like a great idea, especially if it is a BIF (Budget Integrating Sphere.)
I’d get one for a reasonable price.

It’s our ‘BLF’ Integrating Sphere… suggest an alternative size (with a link) and if members like it more, we will switch. Remember that larger might affect packaging and shipping costs a little.

I do not know of any, my point is that larger means less artifact errors
BTW the coating is barium sulfate iirc

Hey Josh, great idea! Put me down for one, please.

yea… There’s a nice used one here for just $2400.00 we’re not pretending to compete with that.
http://www.bmisurplus.com/products/54201-lapshere?gclid=Cj0KEQjwipi4BRD7t6zGl6m75IgBEiQAn7CfF5DijkpvRDI9C7mOIweEMD_t1ptfNxXJBlAA8z1YwNwaAhyb8P8HAQ

Its a nice small(er) size, and i notice there is no direct line of sight from the light source to the sensor.

Yea I planned on that feature too.

I think a BLF IS is a great idea, but a lot more discussion/tweaking is probably going to be needed. Regarding the above, I am not sure that a 15cm IS would be practical/useful, especially with some of the larger (and higher-powered) lights out there. Not to mention, I am guessing that 15cm is an OD measurement, so the actual ID is probably a lot smaller. For those not metrically inclined, 15cm is just a hair shy of 6 inches. You would probably even have issues trying to mount a meter to it. Not to mention, I think the port sizes (source and meter) need to be fairly small in relation to a sphere’s ID, which would be nearly impossible with a 6” sphere used for a variety of different size flashlights. Anyway, good on you for getting the ball (uh, sphere) rolling!

A couple more issues that might be worth discussing/addressing:

  • Ideal sphere size/diameter?
  • Interior coating?
  • Exterior coating?
  • Baffle (size/material/placement/etc.)?
  • Ports (size/material/placement/etc.)?
  • Stand?

Carry on!

obviously the exterior must be coated with 1” thick titanium, how else could we be sure the sphere will resist compression forces from the zombie apocalypse :smiley:

I was thinking pre-preg carbon fiber, cured in an autoclave. But yeah, I guess Ti would be OK. :smiley: