I want to know the answer to the following question:
With what standard is the automatic exposure control system calibrated?
All the background I'm provided with is that "The Standard Output Sensitivity (SOS) technique, also new in the 2006 version of the standard, effectively specifies that the average level in the sRGB image must be 18% gray plus or minus 1/3 stop when the exposure is controlled by an automatic exposure control system calibrated per ISO 2721 and set to the EI with no exposure compensation.". Is that enough to answer the question?
Answer: yes