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drphilmarshall / OM10

Tools for working with the Oguri & Marshall (2010) mock catalog of strong gravitational lenses
MIT License
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-ve magnifications #6

Closed richardgmcmahon closed 10 years ago

richardgmcmahon commented 10 years ago

Hi Phil,

Do the -ve magnifications mean anything special?

i.e. magnifications have +ve values with >1 are mags; <1 are demagnifications but abs(magnif) is used to get the apparent magnitude.

e.g. mi[i] = ms - 2.5*numpy.log10(numpy.abs(mui[i]))

r.

drphilmarshall commented 10 years ago

They indicate the parity of the image, which is important for some applications. If you just want to predict fluxes, take the absolute value.

On Tue, Jul 22, 2014 at 10:48 AM, richardgmcmahon notifications@github.com wrote:

Hi Phil,

Do the -ve magnifications mean anything special?

r.

— Reply to this email directly or view it on GitHub https://github.com/drphilmarshall/OM10/issues/6.

richardgmcmahon commented 10 years ago

Thanks