SBIG file format
Overview over the SBIG file format, like it is used in
WinScan.
WinScan also supports FITS file format (should be preferred)
The file format can be chosen at: Settings Computer
The original SBIG file format, see:
www.sbig.com
There are added a few items to the SBIG file
format
An example of the file header written by WinScan:
ST-7
Image
File_version=3
Data_version=1
Exposure=8413
Focal_length=29.567
Aperture=28.2200
Response_factor=2000.000
Note=Sekunden
je Reihe
0.164969755254731
Background=200
Range=1000
Height=2000
Width=765
Date=12/10/01
Time=11:21:19
Exposure_state=293
Temperature=24.46
Number_exposures=1
Each_exposure=8413
History=R
Observer=Christoph_Flohr
X_pixel_size=0.0090
Y_pixel_size=0.0090
Pedestal=0
E_gain=2.30
User_1=WinScan
User_2=-
User_3=-
User_4=Y2KYear=2001
Filter=None
Readout_mode=0
Track_time=0
Sat_level=65535
An_other_note=ANote1
Shiftime=0.16496975525473
Declination=5.0000000000
Right_ascension=1000.1757600000
TIME_OBS=11:21:18.67
KindImg=DriftScan
End
Some explanations:
ST-7 Image
- WinScan can only store uncompressed
images
File_version=3
Data_version=1
Exposure=8413
- in
1/100 seconds =84.13 seconds
- drift scan images: effective
exposure time, =
the time, a star needs to move over the CCD=
number of lines of the CCD * Shiftime
if there are read in
fewer lines, with open
- shutter, as lines are on the CCD
-
Exposure = Shiftime * lines read in while shutter open
- Standard
image: Time the shutter is open
- sub array image: The time, one
sub array is exposed
- speckle image: The time one sub array of
the speckle image is exposed
- fast scan image: The time, to read
out one line, same as Shiftime
Focal_length=29.567
- in inch
Aperture=28.2200
- in inch^2
Response_factor=2000.000
Note=Sekunden je Reihe
0.164969755254731
- The time to read out one line, see: Shiftime
Background=200
Range=1000
Height=2000
Width=765
Date=12/10/01
Time=11:21:19
-should
be UT
Exposure_state=293
Temperature=24.46
Number_exposures=1
Each_exposure=8413
-same
as Exposure, as WinScan does not support track and
accumulate
History=R
Observer=Christoph_Flohr
X_pixel_size=0.0090
Y_pixel_size=0.0090
Pedestal=0
E_gain=2.30
User_1=WinScan
User_2=-
User_3=-
User_4=Y2KYear=2001
Filter=None
Readout_mode=0
Track_time=0
Sat_level=65535
An_other_note=ANote1
-
a comment
Shiftime=0.16496975525473
- The time to read out one
line
not used for Standard images and sub array images
This
is calculated in the settings form for drift scan images form focal
length, declination, pixel height and sidereal rate.
For speckle
images and fast scan images this is filled in in the settings form.
To check, if the shifttime is reached, check the timestamp data.
Declination=5.0000000000
- form the settings form
Right_ascension=1000.1757600000
- in the settings
information's form the RA of the start of the image can be filled in,
processing the image in ViewScan may change this
if unknown, set
to 1000
TIME_OBS=11:21:18.67
- same as time
KindImg=DriftScan
-kind of image:
- 'DriftScan' for drift
scan images
- 'Standard' for standard images
- 'SubArray' for
sub array images
- 'Speckle' for speckle images
- 'FastScan'
for fast scan images
End