SBIG STC-428-OEM CAMERA
USER’S MANUAL
29
e)
Configure the parameters in the
Stack
form
’s
remaining tabs as
required:
•
Select the
Quality
tab to configure parameters that limit which files
will be stacked, based on various quality criteria.
•
Select the
Align
tab to enable precise alignment of images. This is
useful if a certain amount of shift from image to image is present for
one reason or another.
•
If you are using a filter wheel then select the
Color
tab to customize
the color balance settings, if desired. Otherwise click the
Defaults
button, which assumes 1:1:1 color balance.
The parameters contained in these tabs are explained in detail in the
Help file. Refer to the
Image Processing
–
Stacking
tutorial.
f)
Select the
Combine
tab and set the
Combine Method
. For large numbers
of images, try using
Sigma Clip
- a
Sigma Factor
of 3 is a good starting
point. If you have a modest number of images, the
SD Mask
mode will
produce a better result but will take more time - a good starting point is
a
Sigma Factor
of 0.5 and
Number of Passes
set to 3.
The remaining Combine parameters and options are detailed in the Help
file. Set these as required.
g)
Click
Go
to start the stacking process. This may take some time, so you
can interrupt and restart the process if needed. If you have multiple
image groups, they will be stacked separately. Color sets will
automatically be color combined.
When the combining process completes, the final product is a calibrated
master light frame that can be used as a basis for any further image
processing.
You can save this image in a number of different formats. The FITS (Flexible
Image Transport System) file is the standard file format used in astronomical
applications. It includes extensive support for header information to describe
the image, along with the equipment and procedures used to produce it. The
FITS file can also save your images in floating point format, which will better
preserve the full data range after stacking.
For other applications, we recommend using 16-bit TIFF images. The choice of
TIFF or FITS can be set under:
File
menu >
Settings
>
Files
tab >
Default File
Extensions Setting
. This determines the default file type created when MaxIm
LT takes images.
