Endy:Klett colorimeter

From OpenWetWare

The klett machine is useful for taking OD's without needing to actually remove samples from your culture.


  1. Turn the knob on the power source to 100% and let the bulb warm for 5 minutes
    • Note: make sure the switch on the right hand side of the machine is set to off, only turn that switch on when there is a sample in the light path to avoid damaging the machine.
    • If the light does not come on the bulb may be out, also check that the power switch is turned on and the switch on the light itself is on.
  2. Set the reading to zero by turning the knob on the face of the machine.
  3. Zero the machine by turning the knob on the top of the machine until the red arrow and line are aligned.
  4. Insert a blank, flip the switch on the side of the machine to on and align the red arrow and line by turning the knob at the back of the machine.
    • You will need to blank the machine for any samples taken during the 1st hour the lamp is on since the intensity will be fluctuating.
  5. Flip the switch on the side of the machine to off and remove blank.
  6. Insert sample and flip switch onside of machine to on
  7. Turn knob on face of machine until arrow aligns, and then the value on the meter is the Klett reading for your sample.
  8. The power source can be left at 30% to keep bulb warm if you aren't spending much time between samples. (<2hrs) Otherwise turn the power to 0% and turn back on for next sample.


  • Max volume in 250ml Klett flasks is 40ml.
  • Klett flasks are located in the glassware cabinet in the main hallway outside 68-558D
  • Klett machine is located on Sri's bench

Calibration Curve