WFC3 Data Handbook V. 4.0

help@stsci.edu

2.3	Data Storage Requirements

•	Users are reminded to consider the large size of UVIS and IR images when allocating disk space for storing and reprocessing WFC3 data. The sizes of WFC3 data files (in MB) are given in Table 2.6. The following assumptions were made when calculating these sizes:

•	the ERR, DQ, SAMP, and TIME arrays are null in the raw files,

•	the SAMP and TIME arrays are null in the ima files,

•	IR images have the maximum of 16 MultiAccum readouts, and

•	images are full-frame and unbinned.

Table 2.6: Sizes of WFC3 data files.

Channel	Size of FITS file
	raw	ima	cal	drz
UVIS	35 MB		168 MB	214 MB
IR	34 MB	168 MB	17 MB	13 MB

The size of the drizzled image (Sdrz) is for a single image that is drizzled only for the purpose of performing geometric corrections and for combining the two UVIS chips. It assumes that the input and output image pixels are approximately the same size (drizzle scale parameter is 1.0).