From: Roger N. Clark (change username to rnclark) on
Ilya Zakharevich wrote:

>> > the QE of digital sensor which produces noise similar to Velvia 50
>> > is about 0.004;
> Anybody who can read would see that this is a discussion of the noise
> of the film camera, not of a digital camera.

Noun = QE
Verb = is

QE refers to what? "of digital sensor"