Intracluster light is the wrong color in DR9/north

[djschlegel]

John has noticed that the intracluster light profiles are too green in DR9/north, apparently due to a change in the z-band sky levels. The suspicion is that the CP used for DR9 did more high-spatial-frequency filtering for MzLS.

Here's one comparison of DR8 vs. DR9:
https://www.legacysurvey.org/viewer-dev?ra=250.0824&dec=46.7115&layer=ls-dr9-north&zoom=14
https://www.legacysurvey.org/viewer-dev?ra=250.0824&dec=46.7115&layer=ls-dr8&zoom=14

It looks like this issue is pretty prevalent. Here are 50 clusters all at Dec>32:
https://www.legacysurvey.org/viewer-dev/?ra=126.3773&dec=47.1332&layer=ls-dr9-north&zoom=14&catalog=tmpqp1ehsu0#

[rongpu]

It looks like large galaxies are also affected, e.g., DR9 vs DR8 vs DR6 vs SDSS:
https://www.legacysurvey.org/viewer-dev/?ra=232.4360&dec=42.8773&layer=ls-dr9-north&zoom=12&sga
https://www.legacysurvey.org/viewer-dev/?ra=232.4360&dec=42.8773&layer=ls-dr8-north&zoom=12&sga
https://www.legacysurvey.org/viewer-dev/?ra=232.4360&dec=42.8773&layer=mzls+bass-dr6&zoom=12&sga
https://www.legacysurvey.org/viewer-dev/?ra=232.4360&dec=42.8773&layer=sdss&zoom=12&sga