› Forums › Variable Stars › Valid filters for photometry? › CR ?
20 October 2019 at 12:17 pm
#581510
![](https://britastro.org/wp-content/uploads/2016/11/picture-146-1478110706-80x80.jpg)
Participant
Hi Andy,
With completely unfiltered CCD measurements (ie without cutting the IR) I vaguely remember something about CR (ie using R comparison star magnitudes) correlating better because of the extended response. Do you know if this is the case ?
Cheers
Robin