To use Charon to examine drift scan images,
fill in the
settings in Charon like this:
|
Report file name |
mpc.log |
Saturation point |
32000 |
|
Cutoff point |
0.950 |
Focal len (inches) |
29.53 |
|
Image offset |
0 |
Pix width (microns) |
9.00 |
|
Scale tolerance |
0.010 |
Pix height(microns) |
9.00 |
|
Search distance |
0.50 |
Image is uninverted |
|
|
Observer code |
0 |
Match to GSC-ACT |
|
|
Time offset |
0.0 |
File date gives end of exposure |
|
|
Maximum residual |
1.0 |
Mag limit: |
18.00 |
|
Number stars used |
7 |
D:\GJG\TAU20.ST7 |
|
|
White stars on black |
Object name: |
GSC 1267 237 |
|
|
RA/dec in decimal seconds |
Simple centroiding |
||
|
Video mode: |
320 x 200 |
Max tilt angle: |
90.00 +/- 4.00 |
|
Linear (first-order) fit |
Photometric band: |
||
|
Centroid size |
5 |
Save settings |
Charon will calculate a correct mid exposure time.
( but
only outside the ramping )
The time and date in the file info of
an image taken by SCAN, will indicate the time, when the first line
of the image is read out. Nevertheless/therefore in Charon it is
necessary to set: File date gives end of exposure
In files sliced
from JimsSilce or ViewScan the time in the file info is also the
time, the first line (of the new file) is read out, same settings as
mentioned before.
It is also important to set: Image is uninverted
and :
Max tilt angle: 90.00 +/- 4.00
(Max tilt angle: 90.00 +/-
1.00 should also work)
(In images taken by SCAN West is at the
top)
In large images,it should be set:
Maximum residual
2.0
Search distance 2 or 4 or more, depends on the size of the
image
If Charon don't works with that settings, try to change
some items
It may be easier to use smaller or sliced images
(I
got Charon work with images up to 765 * 10000 pixels, but the
settings in Charon have to be adjusted carefully)
In large
images, it may help, to fill in the exact RA and DEC of the center of
the image (at Object name).
Video mode: try different settings