As already described in the technical description, the SHARP II+
camera provides three different image scales.
For most observations the 
scale is recommended.
When observing in K-band, this pixel scale provides full Nyquist sampling
of the diffraction limited point spread function ( 3 pixels per FWHM
). Even for J- and H-band, this pixel scale samples the point spread
function accurately enough, when observing under average seeing conditions.
For extraordinary seeing conditions or if the field of view is of
minor interest, the 
scale is recommended.
The 
scale with its larger field of view is very
useful in the beginning of the observations for finding the object of
interest
within a crowded field. The larger field of view also helps the
observer in searching for yet unknown objects and mapping larger
areas on the sky.
Beside this advantages, the scale has
several disadvantages. First, there is vignetting of about 20 % towards
the corner of the field of view. Second, in the present configuration
the ADONIS field of view is somewhat too small for recording sky frames
by moving the ON/OFF mirror.
Third, there is an unavoidable reflection between the detector and the
filters. The center of symmetry is at pixel (74,127).
Table 3.1 summarizes the recommendations.
Table 3.1: Pixel scale and recommended purpose