# FAQ

## General

How can I contribute to Cartes du Ciel-SkyChart?

You can contribute in several ways:

- Try the last development version and report the bugs you find to the bug tracker.
- Volunteer to write copy, or edit this text to solve spelling and grammatical errors.
- Translate the program, or this web text into your native language.
- Review the program code and propose your own improvements.
- Please send me your ideas, I am interested in your suggestions.

So version 3.10 is more recent that 3.8 ?

Yes, the version number is not a decimal number but a combination of two number separated by a dot.

The first number “3” is the major version, it normally change only if the new version is incompatible with the previous one. The last time it occur was from 2 to 3 in 2010. A new change is not planned for now.

The second number “8” or “10” is the minor version, it change at each release of a stable version. An even number indicate a stable version. The odd minor numbers are used for the development and the intermediate beta version.

## Installation

I have Cartes du Ciel-SkyChart version 2.76. What do I need to do to run the new version 3? How many files do I download and do I delete 2.76 first?

You just need to install the version 3.0 for Windows in the same directory as the version 2.76. Do not try to install in another directory, and do not delete anything because you can use the two versions at the same time. This is useful to validate that the V3 work fine for you. Run cdc.exe for the V3.0 or ciel.exe for the V2.76

Are the earlier catalogs associated with CdC V2.76 compatible with Cartes du Ciel-SkyChart V3 ?

Yes, all these catalogs can be used with the version 3.0. The only exception is the external catalog, they are replaced by the more convenient Catgen text catalog or the Virtual Observatory catalog.

Where do I install the extra catalogues under Linux, in which directory do they go into?

If you have root permissions, it is best to put them in /usr/share/skychart/cat to have them with the basic catalogs. But you can also install them anywhere as long as you specify the full path in the catalog configuration menu.

Can I get Cartes du Ciel-SkyChart software for a Macintosh?

Yes, the version 3 now work the same on Mac OS X than on Windows or Linux. Look at the specific installation instruction for more information about the additional software you need to pilot a telescope or compute the artificial satellites.

What can I do with MySQL?

MySQL was used as the default database up to the version alpha 7. Since June 2005 it is replaced by the more simple SQLite. You can still use MySQL if required but it is now depreciated and will be removed after the release of version 4.2. The database is used to store the following data: asteroids and comets elements, object pictures and world locations.

## Usage

I need black colors as I can see in some screenshot here

The program itself no more try to change the system color because this is depreciated.
You need to set a dark system theme to change the color, in this case compatible icons are used.

- On Linux: Use a dark Gtk2 theme, for example Adwaita-dark
- On macOS: Since macOS 10.14 you can set a dark theme in the preferences.
- On Windows:
  - Download a compatible dark theme, for example GreyEveTheme
  - Extract the zip and double click on the .theme file

Does Cartes du Ciel-SkyChart V3.0 for Mac/Linux support telescope tracking?

Yes, Cartes du Ciel-SkyChart V3.0 can use INDI to interface the telescope. Any telescope model supported by INDI must work with Cartes du Ciel-SkyChart. Also you can use the include interface for Meade/LX200 protocol or a simple encoder interface.
The ASCOM standard is specific for Windows and can be run only with this platform.
The new ASCOM Alpaca protocol is supported on all the platforms.

There is no “follow” and “see” telescope in the telescope menu of the V3.0?

There is now a Track telescope entry in the Telescope menu
You can also use the “lock on” feature (the anchor button). When the telescope is connected and no other object is selected, this button locks on the telescope.

Why is the sky blue?

Because it is daytime or the Moon is up. You can change that from the configuration menu, Display → Sky colour. Or change the date / time in the program by Setup → Time. Or change the coordinates system from Alt/Az to one of the other systems by a click on one of the icons on the left bar in the Coordinates system group

How can I see a sky chart with simulation of the planets before 3000 B.C?

Since the version 3.9 you can use the JPL ephemeris DE431 that extend the computation range for the planet to -13000 → +17000.

How can I switch the language from English to my language?

The language is normally detected automatically when you start the program. The menu Setup → General → Language gives you the opportunity to select another language.

Does Cartes du Ciel-SkyChart V3 have DDE support?

No, the standard communication protocol for the V3 is TCP/IP for portability reasons.

Does Cartes du Ciel-SkyChart V3.10 for Windows support Windows 10?

Yes, all the current version of Windows are supported.

## Common Problems

On Mac OS X you cannot reopen the program after it minimize to dock

This is a bug with the current version of Qt.
To re-open the program you have to right click on the dock icon, select “Show All Windows” and click on the small windows image.
You can also uncheck “Minimize windows into application icon” in System Preferences / Dock.
This bug is fixed since version 4.1.

The 64bit version of the program crash on startup

You need an AMD or Intel 64bit processor more recent than 2005 or 2006 that support the LAHF and SAHF instructions. Otherwise you must use the 32bit version.
See: https://en.wikipedia.org/wiki/X86-64#Older_implementations

On Linux, every character I type in the search box are doubled

This is a bug with some input method. The solution is to install the ibus-gtk package for your system and set ibus as your default input method.
Or if it is not possible to change the default, run skychart with the following command:

    GTK_IM_MODULE=ibus skychart

I've installed CdC V3.0 but program doesn't display stars or objects.

Maybe you have only installed the program. You also have to install the base catalog package, it is normally include with the standard download. Look at Download page and follow instructions in the Installation of extra catalogs.
Are your star catalogs activated? Make sure they are, see the Stars tab from the Setup → Catalog dialog. Another possibility is that you accidentally switched the display of stars off. Check the possibility of the icon in the object group A of the object bar.
Or maybe the cause is hidden in a troubled display filter. Check your settings in the tab Object Filter from the Setup → Chart, Coordinates dialog.

The help do not open, instead there is a message 'Unable to locate HTML Browser'.

This is because of a misconfiguration of your Windows system regarding the default browser.

Take the following action in sequence:

- Be sure you have a web browser installed and fully functional on your computer.

- From the Windows Start menu select “Default Programs”, in the new window select “Set program access and computer defaults”, select your preferred program for “default web browser”.

- From the Windows Start menu select “All programs”, Accessories“, “Command prompt”. In the command line window type

      path

  and press enter key. Check that C:\Windows\system32 is include in the result line.
  If not do the following:

  - Open the Windows Control Panel, select “System and security”, “System”. On the left pane select “Advanced system settings”. Click the button “Environment Variables…”.
    Look for a PATH variable in both the user and system variables. Select the row, click the Edit button and add “C:\Windows\system32;” at the beginning of the row “Variable value”.
    You may need to restart your computer to be sure the change take effect.

- Return to the command prompt window.
  Type (copy/paste) this command:

      rundll32.exe url.dll,FileProtocolHandler "C:\Program Files\Ciel\doc\wiki_doc\en\documentation\start.html"

  Your web browser must open the help start page. If not, read any error message that can help to investigate further.