This work addresses the problem of assigning confidence intervals to e
stimated photometry data obtained from astronomical observations. The
proposed solution is to estimate the Cramer-Rao bound, which is an ana
lytical expression that describes the minimum obtainable mean square e
rror associated with a given estimate of a parameter. This Letter pres
ents a compact and simple form for the bound associated with a linear
estimator such as a Wiener filter estimator. A prescription for estima
ting the variance associated with each element in a restored object wa
s developed using an analytical model for observed data corrupted by e
ither Poisson or Gaussian noise. Both one- and two-dimensional example
s are presented.