The images directory contains jpeg2000 images by
year, month, day, filter, then filename.

The synoptic directory contains FITS files at a 2-minute
cadence reduced to 1024x1024 2.4 arc-sec pixels by summing
with pixel value in DN per original 0.6 arc-sec pixel by
year, month, day, hour, and filename. The AIA synoptic
images are at data level 1.5. These images are produced
approximately 7 days after T_OBS since they are derived
from definitive level 1 data.

As a convenience, similar NRT images are produced at a
3-minute cadence in the synoptic/nrt directory hierarchy
with a 15 to 20 minute latency from T_OBS. Because of
various latencies and parallelisms in the level 0 and
level 1 NRT pipelines, data are occasionally produced
out of time order. Gaps in NRT AIA synoptic data do not
get filled.