Ha Alberto thanks for the info. Do you want to know why I asked this to you?
I already did the Nagel Anomaloscope in Holland and I had strange feelings after the test.
This white blue machine had indeed 2 turning knobs to adjust the colour and intesity. The lady from the AMC told me to use ONLY the lower knob and not the upper one. I spoke to more people (who did this test in another country) and the told me that you have to use 2 turning knobs to be successful.
I talked to the lady and she really said only the lower knob.
This is a link wirh a picture of the machine. It is exactly the one that I used.
http://www.argusoptik.hu/minimum_elemei/hmc.htm
If someone can give me some advice I would be thankfull
Regards
White