A mini DIY integrating sphere: Possible

[contactcr]

@clientequator

If you make own light integrating sphere, what is the best method to calibrate? I am thinking that you use a known brightness source (say 500 lumen), but where do you find such a source of ‘reference brightness’ lamp? djozz, do you use a specific reference light to calibrate your tests? I would like to know what the best way is. Thank you sir!

This thread has the answers you seek: WTS: Calibration lights for DIY integrating spheres / lumen tubes - 67 € -