|The CCD-based auroral
camera used by Space Physics group of
Oulu is a fully digital Apogee AP7; it is connected straight to the
computer with a dedicated controller card. The digital resolution of the
AP7 is 16 bit (i.e. 65536 grey levels). The exposure time can be
selected from 0.02 seconds to almost 3 hours in 0.01 second increments.
The shortest possible time interval between images is 10 s.
The CCD chip is back-illuminated providing high quantum efficiency of
85 % at 680 nm (Fig. 1). The main advantage of the camera is the broad
wavelength range with a good quantum efficiency, which makes it good for
multiple purposes, e.g. for auroral research. Some of the technical
notes are listed below.
AP7 will be installed to a almost similar box that is used in ATV-98.
In the beginning AP7 will be used without interference filters, i.e.
all images will be obtained with white light.
Imaging software should take care of continuous dark time imaging
with 10 s time interval. Camera will probably be used without pixel
binning, i.e. images will be 512 * 512 pixels, and required space for
additional information. Used image format is planned to be PNG
or JPEG2000, which are capable to store and compress 16-bit grayscale
images. Collected image data will be
moved for processing with 2 GB Jazz disks. Cameras should be ready and
operating during season 2000-2001.