Wouldn’t it be great if there was a cheap BLF integrating sphere so we can all write excellent reviews and share experiences?
I’ve seen DIY integrating spheres all over BLF, but never a manufacturer. Well, I hope to change that today.
The number 1 problem for a cheap DIY integrating sphere is their unique calibration. By selling a pre-built sphere, we can standardize a factory calibration! And with some user-supplied data points, I can make an App that converts the lux number to lumens for it. EDIT: Yes, they will still be individually tested for deviation and the app will accept your number.
I would buy the meter and sphere, carefully drill holes with jigs, 3D print an adapter for the lux-meter to the sphere, then assemble everything and ship it.
I assume this would take $32 for the meter, $16 average for getting spheres, $8 for my printing and installation of the brackets, $4 sanding labor, $4 for the packaging box and stuffing, $12 postage to you, and $2 prototype waste cost share.
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.
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.
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.
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.
