CNebulaX Handbook (built 1.06.04, September 9th 2006)


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Josι R. Torres


CNebulaX works with two windows: the MAIN MAP (always visible filling the screen) and the TOOLBOX (the tabbed area usually located at the lower left corner of the screen, but can be hidden below the main map or moved to other screen locations). There are many other secondary windows. The VIEWER for instance is a floating window to show pictures and secondary maps. The toolbox is the core of the program and includes all control components in sorted tabs. The toolbox structure mimics a pull down menu (see the picture): top tabs for main entries), right tabs for associated items to each main tab, and sometimes bottom tabs for sub-options associated to a given the secondary tab. This yields more room and a more informative layout: you can view all the information and perform operations in a few clicks. Text tips are displayed if you put the mouse on the element you want to know and wait for a while. The program usage is simple, but you have to learn small tricks and protocols. Here you will find a basic knowledge on the use of the program and some operations not so obvious. I have sorted the operations to allow an easier location of the task you may want to do:



   The first run: CNebulaX configuration

   Running the program: the TOOLBOX

  The VIEWER and the infocards

   Changing the magnification

   Finding objects: the JUMP combo box and Quick DSO picker

   Rotate/Flip the map and horizontal modes

   Overlaying reference circles, CCD frames and eyepieces

   Planetarium, ephemeredes and complementary information

   Navigating through the Sky

  Copy and paste text, maps and pictures. Printing maps

   Making observation lists (or programs)

   Making notes

   Comets, asteroids and planets. Plotting orbital trails

  The CNebulaX main library (Reference)

   Control of LX200 classic telescopes

   Identification of deep sky objects: matching maps and pictures





Update CNebulaX to the latest release, and install all the supplementary databases and updates. Some features (comets, asteroids, orbital trails) are only available in the latest release. Note that there can be discrepancies between the handbook and the CNebulaX version you are using: they may be not synchronised and I am always making improvements.




CNebulaX main page

CNebulaX download page

Setup files and instructions for a basic installation

CNebulaX complements page

Extra databases to expand basic installation

Latest compiled EXE file

CNebulaX latest handbook

Latest modified handbook

CNebulaX FAQ

Root webpage

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• ARRANGEMENT: The toolbox includes several collections of sorted tabs. The eight "MAIN" tabs are placed in the upper area of the toolbox (see the picture). The secondary tabs are vertically arranged in the right area within each Main Menu tab, and lead to specific operations. This arrangement is equivalent to the classical menus in many computer programs, but in my opinion, with the tabs arrangement we get a more practical and informative layout. It was also the most compact way I could find of fitting the viewer together with the controllers, and once used to it, it is really comfortable.





  USE OF TEXT BOXES - There are lots of small text boxes to enter information. After modifying the content of any text box, press the ENTER key to apply the changes you have done. There is no button to apply changes: they are applied pressing ENTER.




The general arrangement of the toolbox (it can change from one release to another) is as follows:


MAIN TABS: they are located in the upper border of the toolbox, and consist of the following tabs:  (1) Main, (2) Info, (3) Prog, (4) Planet, (5) LX200, (6) Edit, (7) Setup, (8) Adds. Let's see what the general purpose of the main and secondary tabs:


Main Tabs



(1) Main: it includes the most practical data and operations associated to the main map.

                   Viewer (most used tab) - it frames the docked viewer and the most usual controllers.

                   Config - configuration of the main map (specifications to setup the map).

                   Observ - notes of the visual appearance of DSOs (only NGC and IC at the moment).

                   Key - legend with the symbols used in the main map.

                   Map - DSOs labels and information associated to the pointer (mouse).


 (2) Info: information for the current object and ephemeredes for planning its observation.

                   Data - Data for the current object (position, classification, charts, rise, etc).

                   Notes - Personal notebook (for your own annotations at the telescope, comments, etc).

                   Day - Plot showing the daily trend (height vs. time) for the Sun, Moon and current object.

                   Month - Month trend (rise, transit and set) for Sun, Moon and the current object.

                   Years - Annual plot (rise, transit and set) for current object, and twilights.

                   Find - Finder view of the current object with independent inversions.


(3) Prog: construction/edition of observation programs (=make/edit observing lists).

                   Database - Select the databases to be used in the cross searches.

                   Cross search - Specify the conditions to fulfil in the cross search, and proceed to it.

                   Manage output - Review, edit and save the list of objects found in the cross search.


(4) Planet: Sky planetarium and ephemeredes for comets, asteroids and main planets

                   Sky - planetarium view for the current object, planets, Sun and Moon

                   Comet - select and map the currently visible comets

                   Ast - select and map the currently visible asteroids

                   Planet - get accurate information of the main planets with the full VSOP87 theory

                   Model - default values and theories for the simulation of planets, asteroids and comets

                   Trace - Monitor annual changes of magnitude, phase, etc, and plot orbital trails.


(5) LX200: Control of LX200 classic telescope (at the moment, it only controls my main telescope)

                   Telescope - connection, speed, motions, slews, synchronization and information

                   Serial port setup - setup of the serial port

                   Port monitor - it shows the data send to or received from the RS232C port


(6) Edit: Send information to the printer or clipboard (maps), and configure the associated options.


(7) Setup: Configure CNebulaX, your telescope, accessories and observing place.

                   Configuration - telescope, eyepieces, limiting magnitude and screen features.

                   Date/Time - change the geographical situation, date, time and time offset.

                   Custom colours - change the colour set (it is saved in the INI file).


(8) Adds: Some operations not classified in the previous tabs or under development

                   Image - overlay maps on pictures to identify objects, and edit undocked images

                   Compile - built DAT/IND files, or re−index existing files (maintenance, do not use it).

                   Errors - correct discrepancies between catalogues (maintenance, do not use it)

                   Overlay - get an external file with header information to overlay it

Secondary tabs



This arrangement corresponds to the latest compiled EXE file in the moment of writing the handbook.


If you detect changes, you can be using either an older or a newer version. Anyway, the essential points will be equally valid.


The Main/Viewer tab includes the most common controllers and the docked viewer. It is the one shown when the program starts, and auto-retrieves the focus in most operations because its utility for performing general operations.


  For further sections, it will be followed this convention: a given combination MainTab-SecondaryTab will be expressed as Main/Secondary, for instance: "Prog/Cross search" or "Info/Notes". The main frame shown when the program is activated is the "Main/Viewer" tab.


• SWITCH BETWEEN NORMAL/MAXIMISED VIEW: The usual way is running CNebulaX maximised, filling the whole screen. However, a more compact view can be sometimes of interest. This can be accessed from the maximise-minimise icon in the toolbox (blue icon in the upper-right area in the Main/Viewer tab). To return to the maximised view, click on the same icon again. The program is never minimised: it can only be in the normal or maximised modes. The way of changing the window modes is somewhat awkward, but it works. However, you should avoid setting the program in normal mode (it is not recommended).


• CLOSING CNebulaX AND SAVING THE INI FILE: There are two ways of closing the program:


       (1) Close icon in the Toolbox

       (2) Close icon in the Main Map


   In the current version, both close icons end the program showing the SAVE INI dialog (it allows saving the configuration at your will). If you accept saving the configuration and have loaded or created an observing program, the close dialog also saves it. There are extra buttons to save specifically the INI file (Setup/Configuration tab, "Save INI" button) and the observation list or program (Prog/Manage Output tab, "Save" button).





• MOVE THE TOOLBOX: As mentioned, the toolbox is situated in the lower left corner of the screen. However, sometimes you'd rather put it in another place. Moving it is easy: just double click on any of the upper tab captions of the toolbox (i.e., the main tabs), holding the button after the second click. Then, without releasing the button, drag the toolbox to the place you wish. Finally, release the mouse button.



The Viewer and the infocards

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• DISPLAYING THE DATA FOR THE OBJECTS IN THE MAP (picture, map or finder map) Right click with the mouse on the symbol of any object plotted within the main map. This will display the "infocard" with the data of the nearest object to the clicked point.


  The basic information will be shown in an infocard, that is, a small card with the essential data:


  • Left click on the infocard to close it

  • Right click on the infocard for a pop-up menu


By default, the infocard system works on deep sky objects planets and double stars. If you want to apply it to stars, then you should click on the pointer mode icon (at the left of the clock icon in the toolbox).


For most NGC and some IC objects, the Main/Obser tab shows information about the telescopic appearance. This information has been collected in the net and I have organised it to be accessible in the navigation. If you can get observational info of good quality and you agree sharing it in this altruistic project, send me an ASCII file and I will compile it for the inclusion. My intention is compile a huge database with observations.


More information is given in the Info tab and the associated sub-tabs. The basic data sorted by fields are given in the Info/Data tab. The remaining tabs allow taking notes (and see them), display the basic ephemeredes for the current object (day, month and year views), and an independent map that can be fitted to your finder features. All these plots will be explained in a different section.


The information of the infocards can be altered from the Main/Config tab to full cards or short cards ["Full cards" check box], and with or without rise/transit/set data ["Rise/Set" check box].


• NEXT / PREVIOUS NEAR OBJECT: Click on the buttons with the symbols [<<] and [>>] to jump to the previous and next near object, respectively. You can cycle through the objects situated at a small distance of the clicked point with those buttons. Each time you right click on a new object, the exploration environment is also refreshed for the new object. It is a very comfortable system even to explore very crowded areas.


• THE VIEWER: It is used to display pictures or small maps of the deep sky objects we are selecting. Thus, if the viewer is enabled, each time you right clicking on any object plotted in the main map, the viewer will show:


            (1) its picture

            (2) a small map centred on it

            (3) a finder view, or

            (4) its basic data


   This is whatever the choice you have selected in the viewer mode combo box (Main/Viewer tab).


The viewer can be disabled from the same combo box. In addition, there are two viewer modes:


(1) In the docked mode (default), the viewer is fitted within the toolbox (Main/Viewer tab)

(2) If the viewer is in the undocked mode, it is shown in an independent window


  If the object is shown as a picture, left clicking on the picture will undock the viewer. If you then click again in the undocked viewer window, it will be docked again within the toolbox.


  • Left click on the main map pressing CTRL = it will show the magnified area in the viewer.


• DISPLAYING PICTURES IN THE VIEWER: CNebulaX is designed to show pictures, but I cannot provide any image collection. If you download images from the net, or buy from somebody else an image CD, NebulaX would be able to display them.


My release for personal use includes a large image database including about 150,000 images of deep sky objects from POSS and other sources (virtually, one picture for any displayed object in a mean-expanded basic installation). Each time I click on an object, the viewer plots it. For doing it, however, the image file should follow certain rules for the name, and be located in a folder named as the object type in NebulaX. For instance, M 76 will be displayed if a file called "M76.JPG" exists on a directory "PLNNB" under the [Imagedb] folder specified in Setup/files. If you have downloaded the NGC/IC project site with the file structure unaltered, the DSS folder can also be specified. I have completed all objects of NGC and IC starting from the NGC/IC collection.


If pictures are not available, the viewer in the photo mode will just plot normal or finder maps (this is, simulating the telrad circles), but if the object is a double star, it simulates it at scale (in the undocked mode), and if it is a variable star, overlaying the magnitudes of neighbouring stars. If you prefer reducing the functionality of the viewer in order to gain speed, just select the "Data only" option button within the main tab of the toolbox, or disable it. You can change the displayed mode at any moment from the viewer mode combo box.


  CNebulaX can display pictures, provided some cautions are kept:

               The allowed formats are GIF or JPG

               Each file name should coincide with the respective object name in the database without spaces: A file for "PK 164+31.1" could be "PK164+31.1.JPG", and "NGC7331.JPG" is a graphic file for NGC 7331   

               The files should be properly stored in the folders indicated in Setup/Config/Files tab


  How do the image folders work? - Three categories of image folders are established:


            USERDB (the name and location are arbitrary) - the user image folder. It is a special folder that can contain unclassified graphic files (without subfolders). It is not recommended to use this folder to store all images since it would slow down the program. However, it can be used for storing a "small" collection (i.e., less than one thousand). By default CNebulaX install a folder called [ImageDB\User]. In USERDB you can specify a second folder with the same functionality than the [ImageDB\User] folder.


            IMAGEDB - the root main image folder, which contains several subfolders, one for each object class (OPNCL, GLOCL, GALXY, CL+NB, PLNNB, BRTNB, etc, see the picture). A given object file should be stored according to its class in the respective subfolder (e.g., "M 97" within PLNNB, "M 31" within GALXY, etc). As just mentioned, IMAGEDB also contain the special folder called "User" for non classified images, similarly to USERDB.


            DSS - The Digital Sky Survey files. If the NGC/IC project has been downloaded for offline browsing and the location of the DSS subfolder properly specified in the Setup/Config/Files tab, the program will display the pictures.


Since the NGC/IC project represents a thorough revision of NGC and IC objects. I have given to DSS higher hierarchy for being displayed. So, the order is: (1) DSS, (2) IMAGEDB, and (3) USERDB. The displayed image corresponds to the first file found following this sequence. There are other special folders/subfolders (i.e., PGC).


There is an icon with a photo machine in the Main/Viewer tab. From there, you can launch a pop-up menu to select a second view of the object (if it there are images in more than one folder), or load any image file in the viewer.


• DOUBLE STARS: Double stars in the main map are displayed as in Herald-Bobroff's Astroatlas, that is, at scale (in NebulaX the scale is, however, logarithmic to extend the plotting range). The double stars are labelled with a separation (number 0-9) / magnitude (character A-E) code. The number indicates the difference in brightness between the main and the secondary component, and the character, a separation class code, being A a very close double stars and E a very sparse double. A very good double star, let's say 6.5 and 6.8 components separated 3.5", will appear labelled in the map as "0C".


  The viewer, if is undocked, plots the stars at scale at would be seen from the viewing distance you have specified in the Setup/Configuration tab. If it is in the docked mode, the image will be slightly smaller




Changing the magnification and customising the maps

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There are several ways to get this, being the most comfortable by dragging the mouse on the main map. Try it, it is really handy.


Just click on the centre of the region you want magnify and drag the map downwards if you want to expand it, or upwards if you want to get a wider view. The zoom caption will show you the target magnification. When you have reached the value you want to set, just release the mouse and the main map will be re-plotted with the new values.

    • ZOOM IN = drag the mouse downwards on the star chart, and release it. The current magnification is displayed in the caption of the zoom box you will see.

    • ZOOM OUT= drag the mouse upwards and release it.

    • CHANGE IN STANDARD STEPS: F1 (greater) - F10 (smaller magnification). There is also an icon in the Main/Viewer tab (symbol: Earth with a magnifier), which displays a pop-up menu for the selection of the most usual magnifications.

    • SLIDER: Alternatively, you can use the slider within the Main/Config tab of the toolbox

    • ZOOM TEXT BOX: Just above the slider, there is a text box where you can specify the degrees you want to apply (vertical scale). As usual, press ENTER to apply changes.

    • SWAP EXPLORATION / DETAIL ZOOMS: The two zoom values (exploring/examining) specified in the Main/Config tab can be swapped by clicking certain icon in the Main tab, with two overlaid (red and blue) magnifiers.

The most important map configuration controls govern the number, size and contrast of stars, and the number of deep sky objects, which are also accessible also from the Main/Viewer tab:


Mag: Map limiting magnitud. Once modified, it is apply while the zoom is not modified.

m-offset: magnitude offset to be added to the automagnitude value. If you want less stars, put a negative value (e.g., 0.5) and if your screen is larger and you want more stars, put a positive value (e.g, +0.5)

r-offset: radius offset that make the stars appearing larger. Introduce a value larger than zero (e.g., +0.5) to enlarge stars, and a negative one (e.g, 0.5) to make them smaller

Level: contrast value, that make the progression in bright soft or more sudden (a value form 1 to 10). A mid value (5) gave a nearly linear increment in star radius.


The Main/Config tab includes other options to customise the maps. There is a set of check boxes (lower left area). Full screen removes the main map caption. Planets activates/desactivates the planets, Sun and Moon. Eq.grid switches the grid of equatorial coordinates. Zenith activates the Earth view (pseudo horizontal mode). Labels removes the labels for identify the objects in the main map. Mag plots/removes the magnitude for stars. Full cards adds extra information (notes) in the infocards. Rise/set adds to the infocard of the active object the instants of rise, transit and set. Varst, Dblst and DSO adds/removes variable stars, double stars and deep sky objects, respectively. Restrict DSO filters the deep sky objects to only plots Messiers, NGCs and ICs. MWay adds/removes the Milky Way. HLeda labels forces to label HyperLEDA galaxies (provided they are plotted), instead of only labelling them at a high magnifications. Finally, Horiz plots/removes the horizon line. All these switches allow a considerable degree of customisation.


The colours of most plotted objects can be changed from the Setup/Custom colours tab. The upper option buttons allows returning to some default colours in single click. The current colour configuration is saved in the INI file, but custom colours are overwritten with default colours if you return to them with the upper option buttons.


Finally, the Main/Map tab includes some other controls. The DSO Labels frame allows selecting the mode in which the stars and deep sky objects will be labelled in the main map. By default, the labels are the name for deep sky objects and variable stars, and a magnitude/distance code for double stars. These values can be replaced by a summary line, magnitude, notes, and some others. The map font can be selected from the button just below, and the check box besides it can set the infocards background to transparent. The check box [do not use caption] displays the pointer information on the main map (lower right area) instead of in its caption.



Finding objects: the JUMP combo box and Quick DSO picker

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Get the Main/Viewer tab of toolbox, and look for an empty combo box (=text+list box) in the upper-right area. This is the Jump combo box.  There are two ways of using this control, which is the CNebulaX generic search facility:


MODE 1 - Enter straightforwardly the object name in the text area of the combo box. After typing the name, do not forget pressing the ENTER key to jump to the object.


MODE 2 - Click the right button to deploy the hidden associated list. You will see a number of predefined targets (the Planets, Sun and Moon, Comets, Asteroids, Herschel'400 or Messier lists, Constellations, and others). You can click on the items in the list to select the target you wish. There are three kind of targets: (1) Direct targets (Sun, Moon and planets) that once clicked, move the map to them, (2) Comets and asteroids, that should be selected specifically from the Planet/Com or Planet/Ast tabs, (3) Lists within the Main Reference (Messiers, Herschel 400, Main stars, etc). This kind of entry activates the main library and the final object should be selected from lists. Once selected an entry in the main reference list, just click on the purple book icon with and "R" to display the list again and make a new choice.


  The reference library also includes dozens of tables that can be clicked to jump to deep sky objects. The use of this facility will be seen later.

Alternatively to Mode-1, you can also use the "Center the map in" box in the Main/Config tab


    • Common objects: If you want to center let's say M22, type "M22" and ENTER, and that's it. NGCs do not require any prefix ("N" or "NGC"), just the number. If the number is 1-110, it is interpreted as belonging to a Messier object, so if you want to center NGC 80 type "N 80", "NGC 80", otherwise you will jump to M 80. There are some other tents of abbreviations, A for Abell, I for IC, etc.


    • Constellations If you select "Constellations" in the combo box entry, a list of constellation will be displayed to select which one you want to see. Click on the one you prefer and the main map will be centered on it without altering the main map magnification. Alternatively, you can type directly in the combo box the constellation code (e.g., Aql, And, Ori, etc). In that case, the constellation will be centered and the magnification changed to get a full view.


    • Planets and others: You can also type a planet name (Mars), Sun or Moon to jump to it (+ENTER, as usually). Minor planets and comets cannot be entered directly, and should be selected from the Planet/Ast and Planet/Com tabs, since they require being first loaded by the system.


    • Equatorial coordinates: You can also input the equatorial coordinates in the "R.A." and "DEC." text boxes. Pressing J (jump) with the map activated shows the jump facility as well. The coordinates are not accessible from the jump combo box.


    • Reference library - You can also use the reference library facility (icon with a book with and R in the cover) to select your target and jump examining the tabulated data. It keeps the position of the last clicked target for an easier navigation: click on the book again and make a new selection when you wish.


Quick DSOs picker


This facility works directly on the "general" database, and allows building quick lists to examine the main objects (data and pictures) by constellations and/or object type. It is activated from the small icon raised in the image below, which deploys [>>] or hides [<<] two interlinked lists: constellations and object class. These lists can be used to see the deep sky objects fulfilling the selection. If you have linked images to CNebulaX, single clicking on the found DSOs (or moving on the list with the arrows keys) will show a picture in the viewer and some extra data. Double click on the list will centre the map in the selected object, and will set it as the active one.


Quick DSOs picker is a new feature included in the 1.05.65rs



Rotate/Flip the map and horizontal modes

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(1) Left click with the mouse in the point you want to center in the main map = center the map at the pointed coordinates.

(2) Alternatively, the arrow keys also move the map to the neighbouring areas.



(1) Rotation textbox (Main/Config tab): write the rotation angle and press ENTER.

(2)  Rotate map icon (Main/Viewer tab): Maps can also be rotated graphically with one of the icons in the Main/Config tab. Once activated the rotation tool, a line will be displayed indicating the tentative direction of the top of the map, which can be changed with the mouse. Once defined the new orientation, click on the map to apply it.






(1)  If your telescope inverts the image once (prism), and you want the maps left-to-right inverted, mark the FLIP-Horiz checkbox. The maps can also mirrored up-to-down by clicking FLIP-Vertical checkbox in the Main/Config tab.

(2) Alternatively: activate the horizontal flip / vertical flip icon (each of them will be highlighted if it has been activated).


DOUBLE INVERSION: If your telescope inverts the image twice (astronomical telescopes), set rotation angle to 180. Alternatively, activate both flip icons.


      Naturally, you can alter these values with the ROTATE MAP facility to match exactly the telescope appearance.


• HORIZONTAL MODES (true- and pseudo- horizontal modes):


CNebulaX includes two horizontal modes (or earth views):


 (1) True horizontal mode - it is accessible from the Planet/Sky tab, but it is not applied to conventional maps since it makes them slower to be plotted. The true horizontal mode is only applied in the two kinds of sky plots accessible from the Planet/Sky tab.

(2) Pseudo-horizontal mode - in practice, it allows plotting maps quite comparable true horizontal maps for zooms <30Ί, but it is faster. It just rotates the chart to point its centre oriented towards the zenith. For telescopic or binocular views, this strategy is far more preferable and completely equivalent to the former horizontal mode. For activating it:


(2a) Zenith check box (Main/Config tab): if checked, the top of the map will be always pointed to the zenith. The default way (unchecked) allows rotating the map freely.


 (2b) There is also an icon in the Main/Viewer tab to activate the horizontal mode.





• RETURN TO THE STANDARD MODE: to return the map to the standard mode (unrotated, unflipped and with the north at the top), you can unmark one by one the icons you have previously clicked to get the inversions/flips, but you can do it in a single operation by clicking the "remove flips & rotations" button with a house (Main/Viewer tab).



Overlaying reference circles, CCD frames and eyepiece fields

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• OVERLAY REFERENCE CIRCLES: By default, a 1 degree black circle is drawn at the map center, surrounded by a 5 degree red circle simulating the finder view. The dimensions of both circles can be changed to whatever value from the text box you will see in the Main/Config tab (leave the box empty to hide the circles). You can also specify more circles separating them by [;] (e.g., "1;2;4;7"). The first circle in the list is the "Main Circle", which will be filled. Do not use this facility to set your eyepiece field, since there is an easier and handier way to overlay eyepieces fields (see below). Reference circle are just that: references that make understanding the map scale easier.


The tip in the Main Circle is always pointed to the zenith and allows referring the maps to the actual orientation in the sky.



Left click with the mouse pressing SHIFT. It displays overlaid the field seen through the current eyepiece. The eyepiece class and focal length can be changed from the Setup/Configuration tab in the toolbox (click on the lower label to activate this). The default eyepiece is one of my favourite, a 22 mm Panoptic. You can specify any other eyepiece selecting the "Other" option button, provided you know its apparent field.


• Move the eyepiece field - Shift + left click in the new location (you can do it repeatedly)

• Hide the eyepiece field - Click on the eyepiece field caption (the label below the eyepiece circle), or refresh the map



• Specify the dimensions - The dimensions can be specified in the (Main/Config tab), with the format: mm.m'xmm.m').

• Rotate the CCD box - Writing the rotation angle in the text box by the "CCD frame" toolbox (+ENTER), or graphically using the rotate CCD frame icon (Main/Viewer tab). This icon works similarly to the rotate field icon: it activates a line pointing the new orientation, which is applied clicking on the map.




Planetarium, basic ephemeredes and complementary information

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• PLANETARIUM: It shows the firmament at the computer clock time, together with the Planets, Sun, Moon and current object (Main/Sky tab). The default view shows a south oriented half horizon, and can be changed to another orientation from the option buttons below. The Sun is surrounded by blue circles that help to visualise the twilight instants. If you push the [activate] button, the planetarium is switched to full screen, that allows to change the date and time, and some other features.


• NIGHT INFO: It is a list that, for the current night, shows twilights, sun, moon and some low-accuracy planetary ephemeredes, together with horizontal data for the main stars. Activate it with the icon showing the moon on the sea (Main/Viewer tab).


• EPHEMEREDES FOR THE CURRENT OBJECT: It shows the azimuth and height evolution for the current object, the Sun and the Moon.



  For periodical variable stars, the instants of maximum or minimum are also given. The most important data (height vs. time) can also be seen graphically in the Info tab (see below).


• SPECIAL INFO PLOTS: In addition, some special plots are displayed to make planning the observation easier:


(a) Daily plot (Info/Day tab)


It shows the height trails vs. time for the Sun, Moon and current object. Daylight conditions (light blue), twilights (dark blue) and moonlight conditions (grey) are also plotted. The actual night window (without Moon and in astronomical conditions) appears plotted as dark area.


Use the mouse to read the data (the last line gives the values for the Sun, Moon and target object). The combo box in the upper left corner allows changing the current object (target) by any of the main planets.

(b) Month plot (Info/Month tab)


A plot showing the instants of upper meridian transit, rise and set for the current object (deep red = rise and set / bright red=transit), and the Moon (grey=rise and set / white = meridian). The night time is represented by the inner black area. Astronomical twilights are the blue lines, and the grey outer areas represent Sunlight time. As above, the combo box in the upper left corner allows changing the current object (target) by any of the main planets. Moon phase is indicated in the top line. The midnight instants are represented by the central yellow line.



(c) Annual plot (Info/Year tab)

This plot allows to visualise the instants of rise, transit and set for the current object (or the planets, using the upper combo box), together with twilights. The midnight instants are represented by the central yellow line.

(d) Finder plot (Info/Find tab)

It simulates the finder area, by specifying the naked-eye weakest star, finder diameter and magnification, and true field. The finder limiting magnitude is by default auto−calculated.


• CALCULATION OF VISIBILITY: It works equally well for stellar and nonstellar objects. Calculation of visibility includes locating the optimal combination of eyepieces, Barlow lenses, and focal reducers.




The prediction system is explained in detail in the auxiliary documentation. To learn how it works, activate the Help pop-up menu, and select the entry "Prediction of visibility". It is based in the direct use of the Blackwell's response surface giving the eye detection performance. It is particularly good for small and faint deep sky objects, but it works even for planets in daylight conditions, or for stars in night conditions.


Activate it by clicking on the icon with an eye. The telescope and night configuration are specified in the Setup/Configuration tab. The results are shown in a table arrangement. Each line corresponds to a combination of eyepiece, barlow lens or focal reducer, from the data you have indicated in the Setup/Configuration tab, "Accessory box" entry (see the picture). The telescope diameter and focal length, the naked-eye limiting magnitude, and the telescope class are used to perform the calculations.


The selected line indicates the best eyepiece combination (in the example, the best combination is a 7 mm with 0.63 focal reducer, which yields a magnification of x225).


TLM is the telescopic limiting magnitude, that is, the faintest star seen at the telescope at that magnification


Most of the remaining figures are non-intuitive and you have to should read the help article to understand them. Darkening is the magnitude darkening of the background owing to the magnification. Backgr is the apparent surface brightness of the background in magnitudes by squared arc second. SBlim is faintest visible surface brightness at that magnification in magnitudes by squared arc second. log(C) is the critical contrast. These are only intermediate calculation results of interest if you have learned the basis of the prediction of visibility system.


Visibility is the final result. If it is larger than zero, the object can be seen. This value is the only one of importance for most observers in practice.


In this case, with my 254 mm Schmidt-Cassegrain, NGC 6277 is at the eye threshold if we set the appropriate eyepiece combination. For instance, this galaxy cannot be seen up to reach ca. x100 because the background is still too luminous for the eye detection capabilities (visibility<0). The larger the visibility value, the easier the object with that eyepiece combination. The best eyepiece combination is thus a 7 mm eyepiece with x0.63 focal reducer-field flattener. If we increase the magnification too much, it becomes too faint to be perceptible. In this case, if the magnification exceeds x500, it is lost again because the eye cannot glimpse a so weakened object.


If the calculations exceed the response surface area, the line is labelled as "[extrap]" indicating that the results should be taken with caution since they come from an extrapolation. NGC 6277 is anyway a hard object under moderately good rural sky (naked-eye limiting magnitude 6.5), since the visibility value is quite close to zero.


Just below the list of magnifications, you will see a line telling whether the object can be seen, cannot be seen, or it is at the threshold. Three more lines follow showing the minimal, optimal and maximal magnification at which the object can be seen. Also, the limiting magnitude that can be detected at those magnifications, for both a stellar object and a non-stellar object having the same size that the current one. The last line gives the maximal stellar magnitude and the minimal magnification required to reach a background of 27 magnitudes by squared arc second. This is the magnification that allows reaching the maximal stellar magnitude for your instrument and night conditions.



Navigating through the Sky

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• MAIN MAP CAPTION: It constantly displays information about the position pointed by mouse in the main map, together with the map parameters. You can modify the displayed data from the Main/Map tab. By default, it can be read the following information:




(1) Current zoom (vertical magnification) in the main map

(2) Limiting magnitude (weakest plotted star)

(3) Equatorial coordinates 2000.0 (RA and DEC)

(4) Constellation code

(5) Chart for Uranometria 2000 (first and second edition: u1 and u2)

(6) Chart for Sky Atlas 2000 (s)

(7) Chart for the Millennium atlas (chart and volume,m)

(8) Chart for Herald-Bobroff chart (section C, HBc).

(9) Horizontal coordinates (azimuth and height over the horizon)

(10) Instants of rise, transit through the upper meridian, and set






  Left click pressing ALT while you drag the mouse. Release the mouse button and then the ALT key to return to the normal mode.


• THE NAVIGATOR: For knowing the Sky area where we are (high zooms), to make working at a high magnification easier, there is a special second wide view, called the "navigator" (left upper corner of the main map). You can use it to zoom or quickly change the position in the main map. The navigator allows knowing where we are on a large zoom, and it is useful to jump or change the magnification easily without loosing a high power view of the main map.


The Navigator is by default disabled. There are two ways to activate the navigator:


(1) Click navigator option button in the Main/Config tab. Clicking on the "Navigator" icon shows the navigator, and clicking again will hide it.


(2) Click the navigator icon in the Main/Viewer tab. Clicking again hides it.



• THE FINDER VIEW: It is similar to the Navigator. The viewer includes a special mode (select it from the viewer mode combo box), called "finder". In "finder mode", the viewer shows a wide map whose scale can be changed with the slider at the right. Clicking on the finder map, the main map is centred in the clicked area and the finder, update to that center. However, magnification changes are only available from the navigator or from the main map.



• DSO OBJECTS IN THE FIELD: The data of all plotted objects in the main window can be listed by clicking on the "DSO in the field" button .Clicking repeatedly on the button toggle this region on and off. When it is activated, a list is displayed at the top of the map will the data of all plotted objects:


            (1) Click on the list to jump to any object displayed on the map.

            (2) Click on any object in the map and get the full information in the upper list.




Copy and paste text, maps and pictures. Printing maps.

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• BASIC DATA: NebulaX includes an elaborate way to prepare observation lists (or programs) that we will see later. However, there is also a fast procedure: Each time you right click with the mouse on an object its basic data are copied to the clipboard (just paste it in MS Word and you will get a handy observation program), so you can quickly made an observation program just clicking on the object icons, checking the data, and if you want to store it in your observation program, pasting its data in your text editor. You will get for instance this information set in the clipboard when you right click on M 75:


  NGC6864/M75 20 06.1 -21 55 SGR GLOCL:1/8.6m/6.0' 343u1/144u2/23s/1386-3m/60HBc


  The predictions of visibility and ephemeredes can be saved on disk as well. The clipboard is available to transfer more kind of data.


• IMAGES AND MAPS: From the either Edit tab, from the pop-up menus, or from the Main/Viewer tab a wide variety of maps (from 250-400 to 4000 pixels) can be copied to be pasted further in any other application. Also, pictures can be copied and pasted.


• PASTING DATA: The RTF editor can be used to place your notes at the telescope, but also accept pictures, maps and other data. You can make sketches with Paint or scan them, and paste the images within your own notes.


• PRINTING MAPS: High resolution maps can also be printed from the Edit tab through the windows default printer. A certain degree of customisation can be set:


  (1) Set the line width from the upper left combo box. For laser printers, the lines should be preferably wider (3 points are usually good).

  (2) Modify the star limiting magnitude from the upper slider labelled with "Mag"

  (3) Increase/decrease the star size from the "Star Size" slider. Usually, 2.5 is quite good for laser printers.

  (4) Increase the default deep sky objects from the "Details" slider


You can choose printing monochrome maps (black objects on a white background), colour objects on a white background, or fully customised colours (those specified in the Setup/Custom colours tab). There is a preview facility in the Edit tab (star size is not representative in the preview since the printed area is larger: stars will appear smaller in the printed map).



Making observation lists (or programs)

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  One of the most important features of CNebulaX is making observation lists. Observation lists allows jumping to any included object and plotting marks in the main map, and can be saved for further usage and introduced in word-processing programs. Save and load lists at your will. Observation lists can be generated mainly in two ways that can be used in a cooperative fashion:


• THE PIN ICON: During map exploration, when you find an object you are interested in, first right click on it to make the active object. Then click on the Pin icon (the first icon from the left in the Main/Viewer tab). This will include the object in the observation list, and you will see a circle highlighting it in the map to visualise it. Adds to the observation program can also be done from the main map pop-up menu.


• THE PROG TAB: The most practical way of making lists is from the Prog tab, which includes three secondary tabs that should be used in the following order:


• Database selection: select the database(s) to be used. The default database is "General", a wide−purpose mixed database good for most situations. Don't introduce excessive databases or you will slowdown the program excessively.


• Cross-search: define the conditions to govern the search. If you want to clean all the text entries, press the [Clean] button. Empty fields will not condition the search (i.e., they are not used in the search). A typical search could be for instance finding all planetary nebulae in Sagittarius brighter than 12.5 magnitude and larger than 15 arcseconds above -30Ί declination. When you have set the search conditions, press [Proceed] to make the search. Remember to clean the observation program before proceeding to a new search. If you do not clean it, the new search will be added to the old list. This is indeed a second possibility: make cumulative searches, provided you make a new search keeping the old list without cleaning it. You can remove the duplicated objects using the verify button in the Manage Output tab.


•    Manage output: see and edit the results found, that can be saved on disk, adjoined, or used to explore. Double click on the list to jump to the objects. Click on the name and wait for a while to see the data for the clicked object. The final list can be saved in ASCII format for further use, and cumulative searches are possible to build a composite list.


By default, all the objects that in a given moment are included in the observation list (Prog/Manage Output tab), are plotted in the main map as full circles overlaid without labels. Zooming to >100Ί includes also additional labels. The markers can be hidden un-checking [Plot list] in the mentioned tab. At higher magnifications, if a given object is too faint to be auto displayed, only the circle will indicate that there is an object in the program in that point. In such situations, if you want to write labels for marking all objects, check the box [Force labels]. Also, you can change the colour of the labels and the circles from the same tab.



  That [Manage Output] tab allows some additional facilities:


            Clear:            It empties the list and removes all the markers in the main map

            Load:            Load a previously saved observation program. It can be used in a cumulative way, appending to the current list an older one. After the loading, some objects can be repeated: use the verify button to remove repetitions and sort the merged list.

            Save:            Save the current observation program in the hard drive for further usage.

            Del Marked:  Remove particular entries in the upper list (those one that are marked). To mark several objects and remove them in a single operation, combine mouse left clicks with the keys SHIFT and CTRL, as in any windows application.

            Show:           Display the list in a more complete fashion. Click on the new list to jump to the objects. This list can also be displayed from an icon in the Main/Viewer tab.

            Inverse:         Inverse the selection state (unmark marked lines and vice-versa)

            Verify:           Remove repetitions and sort the list


Besides these procedures, remind that each time you right click on any object plotted in the main map, its basic data are transferred to the clipboard: paste them in a word processing program, or in any window that accept them (the CNebulaX quick notebook, the user notes, etc)


For a quick activation, there is an icon in the Main/Viewer tab that directly displays the full list.



Taking notes

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There are two ways of taking notes:


• QUICK NOTES: CNebulaX includes an area to write down notes of any kind. These quick notes are auto-saved in a text file called Notebook.txt (RootCNebulaXFolder). This file is loaded each time the program is started, so it is a matter of diary. I use the quick notes area to store annotations about the objects I want to observe because present special interest. Normally, once found an object I am interested in, I paste the basic line in the notebook area and I add the comments that moved me to select the object. But naturally, you can write in the notebook any piece of information.


  When you want to return to the map, press either the ESC key or the close button of the main map. The notebook file is auto-saved when you return to the main map, if the program detects changes.


• TAKING NOTES AT THE TELESCOPE: Notes relative to the active object including pictures, maps or photos can be introduced using the Info/Notes tab. The notes are saved in individual files stored in the "notes" folder. If the program detects changes, it will display the save dialog, but you can save the notes at any time pressing the "save" icon.


Advising if the current object includes notes - The notebook icon (quick notes, Main/Viewer tab) changes to indicate whether the active object includes notes or not. When the current object includes additional notes, the icon background becomes green whereas the notebook colour changes form white to yellow.



Comets, asteroids and planets. Plotting orbital trails

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  The release 1.05 includes finally calculation of orbits for comets and minor planets. In addition, it is also prepared for applying the VSOP87 theory (the main planets). Pluto is still not available.




  Go to the Planet/Comet tab. Then specify the search limit in astronomical units (by default, it is 4 AU, beyond which the comets are usually too faint). Finally, push the Load button to search the comets in the database, and load them. If you want to restrict the search, write in the "name pattern" box the name mask to be applied. For instance, if you write "Bro", the comets to be loaded will be "Brorsen", "Pons-Brooks", "Brooks 2", etc. You likely need to extend the AU search limit to load a very distant comet.


  The search text box - You can search the comets in the list: write the search pattern (i.e., "Poj" for Pojmanski), in the search text box, and press ENTER repeatedly up to jump the Pojmanski comet. In this case, there is only one comet matching the search conditions, so you will get it immediately. Once the comet is selected, it is available for centring the map on it (jump button), or for loading the orbital elements to calculate ephemeredes and orbital trails (trace button).


  The Trace button - When you have loaded the currently visible comets filling the list below (for each comet, it lists constellation, magnitude, number and name), they will plotted in the main map and are available to jump to them (select one comet and press the "Jump" button). However, if you want more ephemeredes for a particular comet, then click on the "Trace" button. This will load the orbital elements and activate the Planet/Trace tab, which allows checking how the magnitude, phase angle, elongation, and distances to the Sun and to the Earth changes with the time (combo box above).


  Orbital trails - The trace button also allows tracing the orbit for comets, asteroids and planets covering different periods (1 year, 6 months, 3 months, etc; combo box below). Select the time period and jump to the object to see the trail. For removing the trail selecting "(none)" in the combo box.


  Overlay external tables - In addition to the CNebulaX orbital trails, you can also represent external ephemeredes from the Adds/Overlay tab. Make an ASCII file containing only columns of data, and add a first line with the following decoding characters:


            Identifier: L=labels                                                      [Pojmanski]=      LLLLLLLLL

            Right Ascension: H=hours, M=minutes, S=seconds      [11h12.34m]=      HH MMMMM

                                               [11 12 34.3]=     HH MM SSSS

                                               [11.245]=         HHHHHH

            Declination: +=sign, Ί=degrees, '=minutes, "=arcsec     [11Ί12.34']=      ΊΊ '''''

                                               [11 12 34.3]=     HH '' """"

                                               [11.245]=         ΊΊΊΊΊΊ


  An example with the first 5 rows of a hypothetical file containing a table of ephemeredes, with the corresponding decoding header in the first line could be:


      LLLLLLLLLL    hh mmmmm   +ΊΊ ''''

      2006/02/24    20 14.37 -21 44.2    0.824    0.557 34.2

      2006/03/01    20 22.97 -09 07.6    0.780    0.577 35.6

      2006/03/06    20 36.73 +04 21.2    0.773    0.618 38.5

      2006/03/11    20 54.69 +17 05.9    0.806    0.674 42.4


  Comets at scale - Comets are plotted at scale, orienting the tail opposite to the Sun and with a standard length and size (merely informative) of 10 million kilometres. The comma is also indicative of the comet scale, and by default it is 1 million kilometres width. These figures correspond to perihelium values, and give an indication on how far the comet is and its real orientation in the sky.


  The magnitude of comets is rather uncertain. The default values (Planet/Model tab) allow having an approximate idea of a usual comet, but bright comets are exceptional and can differ strongly. The JPL database used here with ca. 2,500 comets does not include absolute magnitude and slope, and the magnitude previsions are done with the default values, so they must be taken with caution.


  Deep searches - The loading capacity is restricted to 2500 asteroids and 300 comets (far more than enough) in the whole sky. However, you can load a very deep search restricting the search to the current map (marking the respective check box). In this way, you can for instance load asteroids up to 24th magnitude or any known comet, and get an extremely deep chart for the region you want.



  The comet database is saved in ASCII file to be easily edited (adding new comets), but if you edit it, be sure you save it in DOS ASCII format




  It has the same structure and similar features than the facilities for comet predictions introduced just above (read it). In this case, however, magnitudes are well known and predictions are reliable. So the search limit is done in this case attending to the visual magnitude. There are ca. 300,000 asteroids, in three databases provided by the Jet Propulsion Laboratory (JPL):


  (1) Brief database (default) -  Asteroid with a common name (ca. 12,000)

  (2) Full database #1 - Secure (numbered) asteroids, with accurate data (ca. 100,000)

  (3) Brief database #2 - Asteroids with inaccurate orbital elements or few observed (ca. 200,000)


  The brief database covers by far all the needs of amateurs and it is fast to load, so use it except for power searches. The default magnitude parameters can be specified in the Planet/Model tab.


  You can specify a name pattern if you want to restrict the search to a few, or a singe asteroid. Also, you can restrict the loading to the asteroids appearing in the current chart. The result list will show the asteroids sorted by constellations and visual magnitude.


  The asteroid databases are also saved in ASCII file to be easily edited (adding new asteroids or updating them), but if you edit it, again be sure you save it in DOS ASCII format




  By default, CNebulaX uses a low accuracy theory to predict planets (based on the VSOP82 theory), except when the area is magnified (zoom<25Ί). However, more accurate predictions are available from the Planet/Planet tab. The Trace button here give access to evolution plots in the same way as for comets and asteroids. Also, the planets trails can be plotted form the trace tab. Read the information given above for comets to know the details.


  From the 1.05.65 rs, main planets, asteroids, and comets, are given in topocentric apparent equatorial coordinates, with an accuracy higher than 0.05 arc seconds with regard to USNO ephemeredes. The Moon remains uncorrected, and Pluto is still not implemented (1.05.65rs).



The CNebulaX main library (Reference)

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  This is one of my favourite features (activate it from the book icon with an R in the cover). It includes navigating tables (click on an object row to center that object in the map) through combo boxes. The main use is listing what any constellation contains. But the first combo (on the left) gives access to other very handy sections, including references and thousands of observations found in the internet, lists by DSO type, astrophysical data and so on. Take your time exploring this, IT IS REALLY HUGE.


  Compiling files in the help format is not included in this release yet. If you have a file with information you think could be of interest for other people and would like to include in the reference library, send me the file and I will compile it for the inclusion.


  The use of the library is simple. There are three combo boxes in the top line. The left one is the main combo: deploy it to list the main items. The central combo is the secondary combo and includes the subtopics related to the each main combo entry. Identically, the third combo at the right includes the subtopics associated to each second combo item. Just click on them to deploy the information. There are quite tables listing brief data: clicking on them will move the main map to the listed objects. To refresh the screen, change the main combo item to another one.


  Each time you leave the reference library, the position within the list is kept. Thus, just click again the Ref icon and you will be ready to follow with the data in the same place where you were.



  The command controls in the second line are:


• Autocons: if it is checked, the constellation list is changed to follow the active object in the Main Map

• Get Constel: pressing the button changes once the list to the constellation of the active object

• Search facility: type in the textbox the string to be searched in the list below. Then press the find button repeatedly up to get the line you want to locate. Finally, press the jump button to center the map in the object found.

• Bookmarks: The remaining buttons in the second row set up to three bookmarks in the help system. Once set a marker (set button), clicking in the respective go button will move the help system to the stored bookmark.



Control of LX200 classic telescopes

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  NebulaX was originally designed to assist my 10" Meade LX200 classic, and it includes controls to govern it. I have had no opportunities to try other telescopes, but I am considering implement the ASCOM standard in the near future. At the moment, the current LX200 control can be used in other telescopes with emulating interfaces.


  The interface is transparent: the orders sent to or received from the serial port can be seen in a monitor (LX200/Port monitor tab). There are two ways of slewing the telescope to point an object. First you should configure the RS232C (LX200/Serial port setup), and open the connection (LX200/Telescope tab). Then, you can govern it very easily from the Main/Viewer tab, or from the LX200/Telescope tab:


  (1) By clicking the icon with a telescope in the Main/Viewer tab. For doing this, first right click on the object in order to make it the active object. Then press the small icon with the telescope icon to slew to it (Main/Viewer tab).


       In the LX200/Telescope tab you will find another command button for activate slews.


  (2) By clicking a special icon with a gear wheel (a button that as in (1) is placed in the last row of the Main/Viewer tab). For doing this, first click on that toolbox icon: you will see that a gear will appear in the middle of the main map. Now click on this new gear icon holding the mouse, and drag it to the place where you want to point the telescope, releasing the mouse. You can repeat the click+hold movement up to situate it exactly where you want. Finally, click again in the toolbox icon, and the telescope will move to point the target place.




Similarly, the LX200/Telescope tab have a similar facility (a check box, in this case). When you mark it, the gear wheel to be dragged is shown in the screen centre. Drag it to the target point and press slew telescope (command button above he check box)


(3) Some basic movement arrows can be used from the Main/Viewer tab. This is hidden and should be activated by clicking on the left icon in the same row as (1) and (2), in the Main/Viewer tab.


Additional controls are available in the LX200 main tab: information about position and time sent from the LX200, and synchronisation between telescope and computer.



Identification of deep sky objects: matching maps and pictures

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  This facility is available from the Adds/Image tab. The fitting requires installing the GSC databases (if you have not installed it yet, grab it from the website).


IMPORTANT:    If the toolbox is hidden throughout the next operations, remember that pressing the escape key (ESC) will show it again


  (1) Images should be first resized with an external program if they are larger than the screen when zoomed at 100%, with photoshop, irfanview or whatever similar program. The best performance is when the image fills completely the screen at 100%. At the moment, CNebulaX does not resize them, but it will in next revisions. The program can process rotated images, but should be un-inverted. Flipped images cannot be processed, and should be flipped manually from an external program.


  (2) Go to the Adds/Image tab. Load the picture with the folder button. The picture will be set at the background. Note that the usual appearance of the map will be different: the program will enter in the so-called "markers mode", which allows fitting images and maps. In the markers mode, mouse clicks will place markers on the map instead of re-centring the image. Markers are reference points to match the image with the map.


  (3) You should establish the equivalence between map and picture by setting two pairs of reference points, common to the map and the photo. These 4 points are [Atlas-1] to match with [Photo-1]), and [Atlas-2] to match with [Photo-2]. To establish the equivalences, you can use whatever feature you could identify in the picture that is also plotted in the map: stars, the cores of deep sky objects, a prominent knotty nebula, etc. And you can make corrections by iterations (make a guess and try). The four markers needed are selected with the four option buttons you will see in the toolbox.


  (4) Then press [rotate + scale] button to change scale and orientation. This will rotate and change the magnification of the map, and will return to the normal mode. The centres, however, are not coincident.


  (5) After re-scaling, CNebulaX will return to the normal mode ("markers" check box unelected). Click repeatedly near the central cross to move the map gradually to match the picture. For small corrections, you can also use:


·         The two rotate buttons for slight rotations

·         The four move buttons for slight movements in the final adjustments


       The center can also be adjusted with one or two pairs of reference points with the [Move] button. However, final adjustments are always needed.


  (6) If you discover that you had to do a major correction, or need to re-scale, check again the "Markers" checkbox and repeat the process from step (3).


  (7) When all is at your taste, click the "save" button to save the final image:


·         For saving conventional stars, uncheck the "Markers" checkbox

·         For saving no stars, uncheck the "Stars" checkbox

·         For saving the stars as empty circles check the "Circles" checkbox

·         For saving semi-transparent stars (recommended), check "Markers" and choose the colour you wish (colour diagram button)


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