WISE Imaging and Photometry

Proposed "standard" aperture isophotal thresholds: 23, 22, 18 and 15.5 mag per sq. arcsec for W1, W2, W3, and W4 respectively.

Following plots show some of the large galaxies processed thus far, spread throughout the sky showing the range in the 1-sigma SB threshold. The 1-sig SB depends on the coverage (ie. S/N), the local background and source confusion.

Red points == galaxies at low GLAT (hence confused and suffering high backgrounds), which I (therefore) ignore in my SB analysis.

Cyan dashed line represents the isophotal value that should be universal (ie, we can get it for all galaxies), essentially the 1-sigma isophote at the lowest coverages (around w1cov = 20 for W1, for example).

W1

W2

W3

W4