Raw Image data products
Readout modes
Single
In single mode, the detector is readout after a reset. After the readout, the detector is reset gain. This readout mode has limited utillity and it is meant for engeneering.
The frame contains a single HDU. The data section of the HDU contains the 2048x2048 dataframe. In the header, the following keywords are set
READPROC = F / The frame has been preprocessed after readout READMODE = ‘SINGLE’ / The readmode used to adquire the image
Fowler
Fowler mode is an extension of CDS. The detector is reset, then read n
times, exposed and then read agin n times. The exposure time in this
case is equal to the time between correlated reads.
The frame contains a single HDU. The data section of the HDU contains
a 2048x2048x2n dataframe. The first n layers contain the readouts after
reset and the second n the readouts after the exposure time.
In the header, the following keywords are set
READPROC = F / The frame has been preprocessed after readout READMODE = ‘FOWLER’ / The readmode used to adquire the image READSAMP = 2*n / Number of samples taken
Follow-up-the ramp
In ramp mode, the exposure time is sampled n times.
The frame contains a single HDU. The data section of the HDU contains a 2048x2048xn dataframe. Each layer contains the n-th readouts after reset. In the header, the following keywords are set
READPROC = F / The frame has been preprocessed after readout READMODE = ‘RAMP’ / The readmode used to adquire the image READSAMP = n / Number of samples taken