The figure at the right shows the final MegaCam filter transmission functions.
The same data for the SDSS ugriz filter set are shown in heavier lines.
Note the MegaCam u and g filters are slightly redder than their
The transformation between the Vega and AB magnitude system is
different for the SDSS and MegaCam filters, particularly for the U.
This is shown in the following table:
These numbers are computed for zero airmass.
The colour terms between the two filter sets
can be described by the following equations:
u_Mega = u_SDSS - 0.241 (u_SDSS - g_SDSS)
g_Mega = g_SDSS - 0.153 (g_SDSS - r_SDSS)
r_Mega = r_SDSS - 0.024 (g_SDSS - r_SDSS)
i_Mega = i_SDSS - 0.085 (r_SDSS - i_SDSS) (old)
i_Mega = i_SDSS - 0.003 (r_SDSS - i_SDSS) (new)
z_Mega = z_SDSS + 0.074 (i_SDSS - z_SDSS)
The relations for the griz bands (including the old i-filter) come from the analysis of the
The relation for the u band comes from the
CFHT web pages.
The relation for the new i-filter is derived here.