  In a color X-ray camera, spatial resolution is achieved by means of a
polycapillary optic conducting X-ray photons from small regions on a sample to
distinct energy dispersive pixels on a CCD matrix. At present, the resolution
limit of color X-ray camera systems can go down to several microns and is
mainly restricted to pixel dimensions. The recent development of an efficient
subpixel resolution algorithm allows a release from pixel size, limiting the
resolution only to the quality of the optics. In this work polycapillary
properties that influence the spatial resolution are systematized and assessed
both theoretically and experimentally. It is demonstrated that with the current
technological level reaching one micron resolution is challenging, but
possible.
