John is handed 104 science quality 8x2048x4096 images in 3 bands by his collaborator, and asked to make a target list for a spectroscopic run next week. Targets require photometry good to 0.1 mag and astrometry good to 0.1 arcsec. John was handed these data because he is the most computer-savvy person on his team, and because he knows how to use the awesome package  SCAMP.

He needs

• images whose WCS are aligned well enough to be the starting point for SCAMP, which optimizes the astrometric WCS of overlapping images

He does the following steps:

1. He points his browser to astrometry.net.
2. He uploads a .tar.gz file filled with FITS files.
3. He asks only for first-order (straight TAN) astrometric headers, because he is going to do the hiqh-precision tweak step (to get 0.1 arcsec precision) with SCAMP, which does not know about SIP.
4. He downloads the results in any sensible form; he has no problem with writing code to edit the headers himself if he has to.

He doesn't

• mind doing some hacking at his end;
• care about high precision, because he punts that to SCAMP;
• have time to screw around with things that don't get him closer to slamming everything into SCAMP; or
• want to convert headers to a SCAMP-compliant form.