The range of validity of cluster masses and ages derived from broad-band
  photometry
  I analyze the stochastic effects introduced by the sampling of the stellar
initial mass function (SIMF) in the derivation of the individual masses and the
cluster mass function (CMF) from broad-band visible-NIR unresolved photometry.
The classical method of using unweighted UBV photometry to simultaneously
establish ages and extinctions of stellar clusters is found to be unreliable
for clusters older than approx. 30 Ma, even for relatively large cluster
masses. On the other hand, augmenting the filter set to include
longer-wavelength filters and using weights for each filter increases the range
of masses and ages that can be accurately measured with unresolved photometry.
Nevertheless, a relatively large range of masses and ages is found to be
dominated by SIMF sampling effects that render the observed masses useless,
even when using UBVRIJHK photometry.
