raw   snap   red

Speedy Near-IR data Automatic reduction Pipeline

Filippo Mannucci, IRA-CNR, Firenze


SNAP is a new procedure for the automatic reduction of near-IR data based on several existing peaces of software (IRDR, IRAF, Sextractor and Drizzle), allowing for a full reduction  (including double-pass sky subtraction and field distortion correction) with a single command.
For the moment it is optimazed for NICS data and is available on the linux PC brunello in the TNG control room.

SNAP Outline

Using SNAP
> nics [TYPE]   [MOSAIC]


TYPE is type of reduction required, chose one among single, double, and full (default: double).
With single the images are coadded after a simple single-pass sky subtraction;  double performs a double-pass sky subtraction with object masking, appropriate for imaging with the NICS small field optics. full performs the full procedure, with a double-pass sky subtraction with object masking and correction for field distortion.
MOSAIC is the mosaic pattern, chose one among dither, onoff, offon (default: dither);
dither means that all the images are ``on source'',
onoff means that a chopping ON-OFF technique was used, starting  with a ON, so that only even images will be used for sky subtraction and only odd images will be coadded;
offon is the same, but starting with an OFF

A command to reduce the ARNICA image is also present:

> arnica [TYPE]  [MOSAIC]

where TYPE con only be single or double


The needed time to reduce 10 images is about 2/ min (TYPE=double)

Download the full  SNAP 1.1 user manual