I have two questions regarding the alerts and cutouts:
1. Rotation of postage stamps in alert packets
I’ve noticed that the postage stamps included in alert packets appear to vary in orientation across visits, reflecting each visit’s sky rotation. I would like to understand how DI handles this.
Specifically: before running DI,
(i) will the visit image be resampled and rotated to match the template’s orientation (so stamps would always be in template orientation),
(ii) Or is the template rotated to the visit image’s orientation (so stamps retain the visit’s native rotation)?
If it’s the former, does the orientation variation we observed in early alert stamps point to an early production issue rather than expected pipeline behavior?
2. Accessing cutouts before the 80-hour embargo
If I understand correctly, cutouts are accessible in two ways:
(i) from brokers within ~60s of readout,
(ii) via Butler/SIA, but subject to an 80-hour embargo.
However, the Data Products Definition Document (DPDD, sec 3.4.2) states: “Complete difference images will be made available for download no later than 24 hours from the end of visit acquisition.” which seems to directly conflict with my understanding based on RTN-011 (early science). Is the DPDD information stale on this point?
My main question: is there a 3rd way to access cutouts, preferably larger than the 30×30 px stamps in alert packages, before the 80-hour embargo expires?
Thank you in advance.
Best regards,
Satadru