ZTF Image Data Quality

Info about ZTF DQ.

Topics
ZTF data quality
IPAC Exit codes.


Identifying Bad Exposures (June 2026)

ZTF Camera Layout


ZTF camera focal plane layout.
Blue are the CCD controller Archons.
Green are the CCDs.
Red are the readout channels.
Black is the order of quadrants within a CCD.

ZTF image processing exist codes from the IPAC grafana interface

IPAC exit codes for CCD readout channels run from 0 to 63, starting from the top of each image. Individual exposures are distributed along the X-axis. Blank/black rectangles mean there were no error during processing of a readout channel. Other colours represent processing errors of different types. The error colours can change over time and thus do not represent specific errors.


Exposures that failed to process all from Archon 1 (CCDs 3,4,7,8). From 2026-01-25.


Exposures with shutter errors (2025-08-18).


An excess errors just from occuring in CCD 4 (horizontal blue ragions) from 2024-05-16.
The horizontal green section shows errors with noisy CCD number 6.


Irregular errors just occuring from CCDs 1,6,9,14 on 2025-07-03.


Sets of failures across multiple nights from varying Archons 1 and 4 as well as 3 on one night. Taken on 2026-04-01.


Many hours of observations taken through thick clouds causing processing failure for most exposures.


Four hours of observing clouds during the first part of the night.