# Talk:Signal-to-noise ratio (imaging)

${\displaystyle \mu _{\text{sig}}}$ and ${\displaystyle \mu _{\text{bkg}}}$ have exactly the same formula, thus yielding a zero signal; if that is not corrected it must be removed.Fgnievinski (talk) 01:20, 28 March 2010 (UTC)
RMS noise is described as "the square root of the absolute value of the sum of variances" but the absolute value does not appear in the following formula, either as ${\displaystyle |x|}$ or as ${\displaystyle {\sqrt {x^{2}}}}$. —Preceding unsigned comment added by 130.102.119.10 (talk) 01:24, 10 March 2011 (UTC)