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Hubble Space Telescope
Aperture Corrections

This page presents revised calculations of the aperture corrections published in Sirianni et al. (2005, hereafter S05). Tabled corrections on this page are from Bohlin's ISR-II (2011) and ISR-IV (2012).

Table 1

Encircled Energy fractions for K type and hotter stars in 0.5" and 1.0" apertures.

Table 2

Encircled Energy within 0.5" for very cool stars as a function of spectral type. The recommended values are flagged with an asterisk. For spectral type + filter combinations with no asterisk, use the hot star values in column 2, which are copied from Table 1.

Table 3

As for Table 2, except that the Encircled Energy fractions are for a 1.0" aperture.

Table of WFC Encircled Energy corrections from S05.
Table of HRC Encircled Energy corrections from S05.


Last modified on May 11, 2012.