GMOS can perform broad band imaging (using the SDSS filter system) or narrow-band imaging using select filters. The field of view is 5.5 arcmin x 5.5 arcmin (and does not cover the entire CCD package), with two 2.8 arcsec (39 pixel) gaps between the detector chips, as shown below. To cover the gaps it is recommended to use dither steps of at least 5 arcsec in the X-direction.