Why include a reference lamp?

A special Viso reference light source (Reference 800) is included in alle new Viso light measurement systems.

The purpose for supplying this item is to facilitate quick tests of whether the spectrometer properties have drifted, indicating that recalibration is needed. With The REF-800 you avoid wearing on your calibration lamp such as CALI-T50.

The light source has its own power supply, and both parts are labelled with identical calibration date and numbers. Never measure without the original power supply.

Right after factory calibration of your system, the reference light source was measured and a certificate was issued.  The certificate is part of the delivery. The certificate can also be downloaded from Viso’s website using the calibration number on the labels.


With the reference lamp you can quickly check your calibration status:

  • Check whether the total flux in lumen and peak candela is close to the original values
  • Check whether the shape of the spectrum is close to the original shape.
  • Check whether the spectrum looks spiky or jagged.

If you are not happy with the result, the system needs to be calibrated. Viso recommends calibration every year, or minimum every 2 years. Viso provides calibration service, or you may do your own calibrations using the Viso CALI-T50, VISO CALI-DT300 or other traceable calibration light sources.

Check-up Procedure

  • Place the Reference 800 with the indicator (the oblong hole in the base) upwards
  • Do not preheat the light source before measurement
  • Centre the light source in the gonio.
  • Set the measuring distance to 200 cm.
  • Start measurement normal measurement. In the stabilization window, choose “1,0% in 15 min.” and let the measurement finish by itself.