- #36
Alfred Cann
- 82
- 4
Peter Donis:
Aha! After reading a lot more articles about K correction, I finally realized I had a misconception of what it was. I thought it was simply the factor (1+z)^2; it is not. It is a correction or set of corrections applied to photometric measurements through filters when one uses them to estimate what is called a PHOTOMETRIC redshift. That is a crude method, subject to many errors, which one uses only when one cannot collect enough photons to perform a measurement of SPECTROSCOPIC redshift, the accurate method.
So, the articles did not mean to imply that, in cases of single lines or bolometric measurements, the RECEIVED POWER was not modified by the factor (1+z)^2, as I incorrectly inferred. They merely meant that no K correction needs to be applied to the measurement of REDSHIFT in those cases.
Aha! After reading a lot more articles about K correction, I finally realized I had a misconception of what it was. I thought it was simply the factor (1+z)^2; it is not. It is a correction or set of corrections applied to photometric measurements through filters when one uses them to estimate what is called a PHOTOMETRIC redshift. That is a crude method, subject to many errors, which one uses only when one cannot collect enough photons to perform a measurement of SPECTROSCOPIC redshift, the accurate method.
So, the articles did not mean to imply that, in cases of single lines or bolometric measurements, the RECEIVED POWER was not modified by the factor (1+z)^2, as I incorrectly inferred. They merely meant that no K correction needs to be applied to the measurement of REDSHIFT in those cases.