NOTES for wxAstroCapture

This page contains realease notes (top) and some advice relevant to using wxAstroCapture (bottom).

Rev 1.8-1 - 23. October 2010

Rev 1.7-2 - 10. November 2009

Rev 1.7-1 - 08. November 2009

Rev 1.6-3 - 27. April 2009

Rev 1.6-1 - 10. April 2009

Rev 1.5-1 - 15. October 2008

Rev 1.4-1 - 29. September 2008

Rev 1.3-1 - 16. September 2008

Using subframes

In version 1.3 you can capture webcam subframes.

Now you are streaming a subframe, the rest is blurred and static.

To re-enable the fullframe, use the Fullframe button in the toolbar or double right-click in the graphics window.

Rev 1.1-1 - February 2008

Multiple instances

wxAstroCapture can be run in multiple instances - it is useful for guiding and imaging using two separate instances - there are some limitations however.

Ports cannot be shared between instances!

Any parallel port can only be used twice within the same instance of the program. I.e. if you use one instance with a long exposure (LE) webcam on parallel port 1, it can be used for guiding via the same parallel port in the same program instance.

A second program instance can use any other port than parallel port 1.

Settings Dialog

The Settings Dialog for ports contains a tab to set up the webcam long exposure (LE) port and another tab for the guide port. These tabs will be greyed out and inaccessible when either LE exposure or guiding is running i.e. using the port in question.

You have to switch those functions off to get access to the settings.


Autoguiding is currently supported for webcams only. Webcams modified for long exposures can be used.

Port Interface

Select the Port Interface in the Guiding Options, interface tab. Then in the Guide Port tab select the parallel or serial port to be used for guiding. Then select the guiding protocol to be used for that port.

Notice that for the PowerFlex MTS-3 supported is firmware V3.xx, please refer to the LX200 protocol.

File Interface

Select the File Interface in the Guiding Options, interface tab. Set the target folder for X.DAT and Y.DAT text files to contain guiding information. Separate software (not included) is required for guiding using the file interface.

Bridge Interface

Select the Bridge Interface in the Guiding Options, interface tab. This interface allows you to send guiding commands over TCP/IP. A demo program (wxScopeServer) is available in full C++ source code. wxAstroCapture is the TCP/IP client and wxScopeServer is the server. The client and server can run on the same computer (localhost) or over a network. You must specify the host as either an IP address or host name and Port 5618.

For additional information, including how to develop a complete server, please consult this page and/or the wxAstroCapture Yahoo group. We are interested in help from anyone wanting to implement an ASCOM server (MS Windows only) based on the demo.


This version supports imaging with 16bit Artemis/ATK cameras on Windows and Linux

Camera models supported

Tested cameras are Art429 and Art285; ATIK of the same kind may work (ATK-16; ATK-16HR - for colour models there is only raw image support).
Support of ATK-16IC is unknown - we don't have such a camera to test with.
The large format range is not supported (yet??)


For the Artemis cameras a full range of toolbar buttons help to use the camera.
The leftmost item (a star icon) allows to quickly enter the OBJECT property of the FITS file.
Then a dropdown allows to choose the IMAGETYP of the recorded FITS file.
Next is the binning - choose from the dropdown box.
Then Zoom, either type in a factor or use the mouse scroll wheel, you may first have to click the image area with the mouse - the blue arrow icon resets zoomfactor to 1.0.
Fullframe (blue arrow icon) resets the exposed area to full frame.
Restart will just drop the current exposure and start a new one - if a download is in progress it will load it but the image is not saved if capture was requested.

Subframe selection

Using the right mouse button one can choose a subframe in the image area. The next exposure will only capture the choosen area. You may note that the surounding is blured but remains visible until binning is changed - then it gets black until a new full frame is taken. Subframe selection works continuously but you have to wait for the download of an image to have the new selection visible.
To reset the exposed area use the toolbar button (Fullframe).

Image Properties

Using the Properties button in the Record panel Black point, white point and gamma can be adjusted.
There one can (un)check the Auto Histo Stretch box which tries to make a visible image - NOTE: this box is checked by default whenever an Artemis camera is connected.
All settings there do not affect the captured files, they are just useful for live preview.

Exposure meter

Note - the histogram is calculated from the exposed subframe.
For the Art cameras the exposure meter just reports the luminance channel - choosing R,G or B changes the colour but not the content of the histogram.

Artemis camera simulation

To get ready using an Artemis camera with wxAstroCapture you may use a camera simulation.
First get Artemis Sim files from Yahoo group files area, install them according to the readme file.
Once the program finds the image files it will show "Art nnnn Sim" in the camera chooser (Menu Camera - Connect)
While this simulation allows to use all wxAstroCapture features it is still limited to a single frame and also the exposure time range is in the area of 2sec max otherwise the image just gets overexposed and therefore white.
If you don't want the Sim cameras in the chooser you may just remove or rename the files installed.