The one i built above took a bit of time to build, not sure if there is any profit in it for the time and parts used.
I have it calibrated very well now though.
Nice work DBSAR! It looks very handy with all the mounting options around it.
The accurateness of professional spheres has much less to do with the actual sphere, much more with the better measuring equipment and calibrated sources, a home made sphere like we make already has excellent integrating properties.
Good point. for most of us the only way to “calibrate” our Integrating Spheres is calculations based on testing our stock known ANSI measured Lights, in my case is a few fenixes, Nitecores, Olights, thrunites, etc.
For the purpose of consolidating information regarding IS's here are a couple of links for those who may be interested in a source for Barium Sulfate products for the inside coating if one were to choose that method.
This is just one supplier that was mentioned in another forum. It is not known if they are more or less expensive than any others.
Labsphere, Inc.
A Halma Company
P.O. Box 70
231 Shaker Street
North Sutton NH US 03260
+ 1.603.927.4266 (ph)
+ 1.603.927.4694 (fax) labsphere@labsphere.com
Welcome to BLF!
Match’s coating was plain flat white paint without BaSO4 what I remember, but his sphere was made many years ago and Match is not around here anymore.
A BaSO4 coating can indeed be 0.96 if done well, but I doubt that DIY formulations containing BaSO4 will be anything close to that, and even if someone did a good job at it, the experiment for testing the reflective value is difficult without proper laboratory equipment. And then you also want to measure the reflectivity across the spectrum…
I don’t really understand the concepts behind an integrating sphere, I wish there were an affordable one just because I’d like to test my mods. This would certainly be reflective, but aside from putting a hole in it ruining the structural integrity/shape I assume there are many other reasons it wouldn’t work that I’m unaware of. https://www.amazon.com/TONIFUL-Hangable-Aluminum-Metallic-Decoration/dp/B07X655671
Seems like there is a decent market for this and data logging light meters, I’m mildly surprised we don’t see some package deal priced well out of China.