The accuracy of the wavelengths is of the order of a few hundredth of Angstroems. The other setup sections differ whether you are working in imaging or spectroscopy mode. Imaging ETC Filter Choosing the instrument filter determines in which band the observation will be performed. The magnitude parameters for object and sky are defined in the observation band you choose by choosing an instrument filter. It is not possible to define an input spectrum in J and observe it in Ks, for example.
Filters are available for wide and narrow bands.
Click on the filter name to view its transmission curve. Narrow band filter central wavelengths are indicated in microns. Information about these filters can be found at the filter page . The list of available objectives can be selected from the pull-down menu. The Exposure Time Calculator is made of 2 interactive Web forms.