Implement utility functions purely related to survey and filter numbers #24
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aboucaud
changed the title
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We've been using the stuff in wldeblending, so if these functions match that, then it should be good to go. I'd suggest downloading their catalogs and converting the same entries w/ the same survey properties maybe? |
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We'll leave the typical background on a moonless night out of this PR for now. @ismael-mendoza I think I'll merge this branch now |
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| def mag2counts(magnitude, survey_name, filter_name): | ||
| """Convert source magnitude to counts for a given filter of a survey |
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We may mention that it consists of electron counts ?
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But is it really ?
For me, this is photon count. To be electron counts it needs to be multiplied by the gain.
It does not change a thing for LSST because the gain is set to 1.0 but for other surveys this is relevant.
This comes back to another related question about the units of the gain currently in electron/adu that should be changed to electron/count if we would like them to be compatible.
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Hm I think that the conversion from photons to electrons depends on the quantum efficiency while the gain is effectively transforming electrons to ADUs (it is in e-/ADU such that going from e- to ADUs is done by dividing by the gain).
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Coming back to this, as we are using zeropoints indicating magnitudes giving 1e-/s, I would say that the fluxes we compute with those zeropoints should be in e-.
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ping @aboucaud (I don't know if you have a notification as the PR has been merged) |
Tentative implementation of functions for
Fixes #15