6.2 NICMOS Coordinate System Conventions

Figure 6.1 shows how the NICMOS cameras are arranged in the HST field of view. The alignment of each camera is not exact, and the internal coordinate systems attached to each of them differ by small rotations (< 1 degree). The FITS format data files generated for NICMOS observers have a World Coordinate System specified appropriately for each camera. The adopted coordinate system for all three cameras is summarized in Figure 6.1.

Figure 6.1: Common NICMOS Coordinate System