Numerous minor releases of SIMS were released from the v1.0
version. These releases brought many enhancements and we will not
cover them all in this document. Description of these upgrades can be
found in the Products/Software/Articles section of this web site. We
only summarize major enhancements and bug fixes between last SIMS
v1.1.7 and SIPS v2.0.
Major changes are related to SIPS internal workings. Basically,
SIPS v2 become heavily multi-threaded, almost every time-consuming
operation was moved to background. This means the user can
interact with the software during image processing, image download
from the camera etc. Not only the SIPS GUI is much more
responsive, but numerous operations (e.g. attempt to load multiple
images at once) can be simply canceled.
The following operations were moved to background
Image calibration and creation of calibration
Image mathematical operations (filters, processing of
image sets etc.).
Transformations of image sets.
Automatic image matching in Blink and Combine Image
Multiple image load and save.
Image astrometry solution.
Communication with connected camera, including filter
settings, chip clearing, image download etc.
Moving of these operations to background threads not only made
SIPS more responsive, but also opened the possibility to use
modern multi-core CPUs (even the cheapest netbook computer are
capable to process two or four threads in parallel these days).
Not all operations are completely parallelized yet, but doing so
is now relatively easy and more and more time-consuming operations
will utilize the SMP (Symmetric Multi Processing) of modern PCs in
the subsequent minor releases of SIPS.
Also user interface underwent some updates. New mode of
displaying of images in tabbed panes, filling the whole SIPS
workspace, was introduced:
Compared to traditional windowed documents interface:
Switching between these two modes can be performed using
Show images in tabs menu item or directly by clicking of
the corresponding tool .
If images are displayed in individual windows, any attempt to
maximize any window (be it from window menu or by clicking the
maximize button or double-clicking the window title) switches SIPS
workspace to tabbed mode. However, switching back from tabbed mode
to window mode is possible only by clicking of the tool.
SIPS v2 also added the possibility to arrange multiple image
Another small, but quite useful enhancement is the ability to
show cross over every displayed image center. The cross is
displayed when the
tool is checked. The cross does not alter image data, it is only
Marking of the image center can be useful feature for
various observing tasks:
While performing equatorial mount polar adjustment using
drift method. Placing observed star in the field center allows
the user to precisely determine the star drift.
While aligning the mount to sky, displayed cross enables
precise centering of the star in the field of view.
Various other enhancements were introduced in SIPS v2.
SIPS can export images not only to common 8-bit file formats,
where original dynamic range of FITS images is lost (the same
image transformations, used to display images on computer screen,
are used to transform 16 or 32 bit image to 8 bits dynamic range),
but also to 16-bit PNG and TIFF formats. Only 16-bit images can be
exported to 16-bit PNG or TIFF, because no dynamic range
transformation is applied in this case.
There is a possibility to define binning independently for each
captured image in the Series tab of the CCD Camera control
SIPS includes sophisticated algorithm for searching stars in
images. The algorithm uses several parameters to identify stars
properly. Optimal values of these parameters depend on image S/N
ratio, on star FWHM etc. These parameters were common for the
whole SIMS and used for star matching in Astrometry, Combine
Images or Blink tools. These parameters were also used for
searching of a star on images used for automatic guiding.
But typically guiding telscope/camera has very different
properties compared to main imaging telescope and camera. Stars
has different FWHM caused by different telescope focal length and
different pixel size of guiding camera. This is why SIPS started
to use independent set of star search parameters for main
camera/telescope related tasks (astrometry, image matching, ...)
and another set of these parameters for guiding.
Support for new hardware
SIPS v2 supports new hardware devices as well as enhances
All communication with devices utilizing serial line (RS-232C
interface) was also moved to background threads. This affects
mainly drivers for telescope mounts (LX200, NexStar) and
eliminated possible problems with missing of telescope commands,
causing unreliable communication.
New drivers for NMEA-compatible GPS receivers was added to
SIPS. This is widely adopted standard and almost every GPS
receiver is able to communicate with a host PC using NMEA
protocol. NMEA driver also utilizes serial line interface,
similarly to the telescope mount drivers.
Support for newly introduced G0 series of autoguiding and
planetary CCD cameras was added to the G1 camera driver. G0
cameras are basically the same like G1 ones, but camera housing is
smaller and of round shape (similar to an ordinary 1.25"
eyepiece). However, G0 physical shape changes leaded to slightly
different electronic and resulted to driver updates.
It is now possible to create multiple configuration files for
multiple G2, G3 and G4 cooled CCD cameras. For instance if the
user uses G2-3200 camera equipped with photometric BVRI filters
for scientific and research tasks and G3-11000 camera with RGB or
narrow-band filters for aesthetics atrophotography, it
was necessary to use two 'g3ccd.ini' configuration
files, each containing different filter description. One of these
files should be copied to SIMS directory, so the
'g3ccd.dll' driver, used for all G2, G3 and G4 cameras,
can use appropriate .ini file. SIPS includes enhanced
'g3ccd.dll' driver, which looks for an .ini file
containing camera identifier (ID number) in its name first and
general 'g3ccd.ini' file only if the camera-specific
.ini configuration file is not found.
If the user has G2-3200 camera if ID 3200 and G3-11000
camera with ID 11000, if is possible to create two .ini
'g3ccd.3200.ini' file for the G2-3200 camera,
containing BVRI filters description
'g3ccd.11000.ini' file for the G3-11000
camera, containing LRGB filters description
G2, G3 and G4 camera drivers are able to crop the image matrix
even before the image is passed to SIPS. Although it is possible
to define sub-frames directly in SIPS camera control tool,
limiting camera resolution this way is not very convenient when
multiple frames of different types (light, dark, flat) are
acquired. If for instance the user wants to use only center area
of a large CCD because the optics used cannot utilize such large
CCD detector, it is possible to read only a sub-frame (sub-frame
512, 512, 3072, 3072 converts 16Mpx G1-16000 camera into 9MPx
camera). But different sub-frame is used e.g. when focusing the
camera and it is necessary to properly restore above mentioned
subframe before each dark, light of flat field is acquired. And 1
pixel difference between light and dark frame harms the
possibility to properly calibrate images.
This is why the 'g3ccd.dll' driver allows definition
of sub frame in the appropriate .ini file in the [crop]
x = 512
y = 512
w = 3072
h = 3072
Such camera will report resolution 3072 × 3072 pixels to SIPS and all other sub-frames,
defined in the SIPS camera control tools, will be related to the
above defined subframe.
SIPS v2 fixes problems, found in the previous versions
of the software.
Switching of imaging camera in the CCD Camera tool did
not update limits for frame binning. So if e.g. G1 camera was
selected as imaging one, hardware binning limit is 1 pixel (G1
cameras do not support hardware binning). After selecting of G2
camera as imaging camera, binning limit was kept on 1 pixels
instead on 4 pixels (Gx cameras support up to 4 × 4 hardware binning).
Zooming images in various tools (e.g. Blink tool) did not
reflect actual zoom ration in image status bar.
32-bit image, whose dynamic range was stretched to 16
bits using histogram transform could not be saved due to omitted
update of bit depth information in FITS header.
Image rotated by 90 could not
be saved, because rotation did not update image width and depth
in FITS header.
Image crop failed when image was scrolled so the image
upper-left corner was not visible.
Calibrate Immediately option th the Calibration tool did
not work properly when the Calibration tool remained
SIPS v2 is a freeware and can be downloaded from the download section of this WWW site.