[ MISTRAL instrument page ]

MISTRAL observing modes and GUI

(1): Mode to measure the camera offset signal.

(2): Mode to center image on targets (imaging mode), and to focus the telescope. Fast reading with relatively high reading noise. These images are not saved.

(3): The goal is to take science images.

(4): Mode to take flat field images with the goal of correcting the differential spatial CCD response. Has to be done preferentially on the sky (see below), and within each filter. Response is very different from a filter to another one.

(5): Mode to locate the slit “x” position within the CCD before moving the telescope to push the target within the slit. Slit is seen thanks to the sky surface brightness. Images are not saved. Rapid reading mode.

(6): Mode to move the target at the slit position. Rapid reading mode. Images are not saved.

(7): This is the mode to take the spectrum of your science target (blue or red disperser). In principle to be done without regular filters (unless you really have special reasons), and with an order separation filter for the red disperser.

(8): To take wavelength spectral calibrations in order to relate “x” position to wavelength.

(9): To take spectral flat fields in order to correct for CCD differential spectral response.

All these modes are accessible through the following GUI: