Vertical or Horizontal Alignment
Adjustment Origin to destination
Practical advises to use adjustment
Georeference by one point and a distance
Definition of the navigable area
2. To integrate modifications to the original chart
ScanNav charts internal format
« Menu-File-Save (or Save As) »
Menu-File-Optimize for Navigation
Organization of charts on disk
ScanNav Documentation
Charts Workshop
ScanNav opens by default in the mode it was on last usage, and in Navigation mode if it is the first usage.
To open a window in Workshop mode when you were previously in Navigation mode, use the “New” entry of the “File” menu.
The first thing to do is to have images to work with.
To do so, you can directly use the « menu->File->Scan Twain » function to interface any Twain scanner. Nevertheless, I would advise you to scan your maps with your native scanning software, and to save the images to disk in TIFF, GIF, or BMP format (the only formats supported today), to be able to import them later on in ScanNav, this for several reasons:
· You can make mistakes, and it’s good not to have to rescan all files again…
· The demo version inserts a Copyright text in any generated image. So if you want to be able to use the work you’ve done with the evaluation version, later on with the official version, it is better to have the original scan files.
Insert the different scans you want to merge. (To read a image file: Menu->File->Insert)
The current tool is the one currently selected (pressed down)
Moving tool Click with the mouse’s left button on the selected image(s), and drag them where you want.
Manual rotating tool Click with the mouse’s left button on the selected image(s) and drag the mouse to rotate them around their center.
Manual Scaling tool Click with the mouse’s left button on the selected image(s) and drag the mouse to scale them up or down around their center.
Crop tool Enables you to crop an image on its left, right top or bottom side.
Click with the mouse’s left button near a border of the selected image, and drag the mouse keeping the button down. The side that will be cropped depends on the initial movement of the mouse. If this is vertical, it will be the top or bottom side (whichever is nearer the cursor), and if this is horizontal, it will be the left or right side.
The Crop tool definitively suppresses the cropped parts, and only allows horizontal or vertical cropping. To have a more selective cropping, refer to tool number 8 to define the navigable area.
Adjustment Tool This is one of the most important tools of the ScanNav workshop. It enables you to merge several scans to rebuild an entire chart.
WARNING: The image(s) on which the operations will take place is (are) the one(s) selected when you enter this function. So Make sure to select THE and only THE piece you want to adjust!
When you select this tool, the following control box appears:
Proceed as follows:
· Select the operation you want to perform (Vertical or Horizontal alignment, or Adjustment of points)
· Define all the necessary points needed for the selected function: Select one of the « Point » buttons, and click on the map with the mouse’s LEFT button to define the point.
· You can move the selected point using the arrow buttons.
· Click on the « Adjust » button to perform the operation
The number of points needed depend on the selected operation:
Lets you straighten up a map by aligning two points vertically or horizontally. In this mode, you will have to define moving points 1 and 2. When you click on « Adjust », point 2 will move to align vertically or horizontally with point 1. You can also define the « Destination » Point 1. In this case the « Moving » point 1 will move there in the same operation.
For this operation, you have to define all the 4 points. When you click on « Adjust », « Moving Point 1 » will move to « Destination Point 1 » and « Moving Point 2 » will move to « Destination Point 2 », the selected image being transformed in consequence. You can omit one of the « Destination » points. In this case it will be assumed to be at the same position than it’s corresponding « Moving » point.
You may also use this function to perform a simple translation of the selected image. To do so, just select « Moving Point 1 » and « Destination Point 1 » leaving both « Points 2 » undefined.
To leave the adjustment tool, you just have to click on the window's closing cross of the dialog box. In this case, no confirmation is asked, and if an operation is in progress, it is aborted.
You can also leave the function by selecting another current tool. In this case, ScanNav will ask you confirmation. This can be a way of erasing all defined points in a row…
You also can use some keyboard shortcuts:
· « Backspace » key: to erase the current point.
· 1 2 3 and 4 keys: shortcut for selecting the current point. 1 is for « Moving Point 1 », 2 for « Moving Point 2 », 3 for « Destination Point 1 », and 4 for « Destination Point 2 ».
· a z q s keys: shortcut to the control box arrows. They move the current point of one pixel towards left (a), right (z), bottom (q), or top (s). If you leave the key down, the point will keep moving until you release the key.
That’s for the principle. Now, you have to know that you can zoom in and out, and move around the screen with the + and - keys, arrow keys, or using the mouse wheel and center button. You will indeed need to zoom in at a maximum, so as to have a maximum of precision for the definitions of points. (You can zoom out afterwards to move around the map faster). You can also use the zoom-in window so as not to permanently zoom in and out.
So as not to propagate errors while adjusting pieces, it is recommended to proceed as follows:
· Always start the adjustment by a central piece of the chart, and « turn » around it. Most people have the reflex to start from an angle, which means the adjustment errors will propagate from one edge to the other.
· Start adjustment by straightening up the first scan with the vertical or horizontal alignment function. This way it will be easier to visualize errors along the vertical or horizontal axis.
· You can use the georeferencement grid to visualize perfect horizontal and vertical axis on which you can align parallels and meridians. (See hereunder for manipulation of the grid)
· If for some reason or other you’re having trouble to adjust a whole chart (for example if it’s too crumbled, or with too deep folding marks…), don’t insist! In this case, instead of merging the chart in it’s integrality, just make several blocks by merging for example by blocks of 4 pieces, and georeferencing them separately. The blocks will merge together in any case automatically in navigation mode, and the georeference errors will be limited (but the frontier between blocks will me more visible on the screen)
· You can also retouch an adjustment after having georeferenced the chart
Once charts have been merged, you have to georeference them.
ScanNav supports different projection types (Mercator and UTM), and takes in account the Datum specifications for the chart's referencement.
Georeferencement ToolWhen you select this tool, the following control box shows up.
The first tab lets you enter the chart's general parameters
The second tab lets you choose projection and datum parameters:
4 types of projection are supported up to now:
1. Latitude/Longitude projection (equidistant Mercator projection): All the parallels are equally distant each other on one map. This was the only projection type used by ScanNav in the first release. This was sufficient for detailed maps, but the problem of this system is when you start having large-scale charts where you can have a considerable difference concerning latitude intervals at the top and the bottom of the chart. This was resolved with tool number 7 (see next chapter), which can modify the chart to have equidistant latitudes, but also to correct errors due to folds, etc… It is still present for historical reasons, but should not be used anymore.
2. Mercator Projection: It is The projection used for marine charts. This type of projection is supported since release 1.6, so it isn't necessary to correct latitudes with tool 7 anymore
3. UTM Projection: This type of projection is used for topographic maps such as the USGS DRG charts. These are not for navigation usage, but are interesting for hikers or roadrunners, and there are sites where you can download them for free as they are of public domain. You can also use them as a complement to your navigation paper charts, as they also cover all the USA coasts.
4. Lambert Projection: This projection is very much used in land cartography, especially for the French IGN institute. There are several additional parameters to give for the Lambert projection. These can be input through the 2 additional fields of the dialog box that appear when the Lambert projection is selected:
A predefined list contains the Lambert variations used by the IGN French institute. Warning, the Datum is in close relation with these parameters, and is not positioned automatically when choosing one of these entries. You will therefore have to make sure you position it to the appropriate value. Except contradictory advice on the printed map, the Datum must be:
· NTF France: for « Lambert I » « Lambert II » « Lambert III » « Lambert IV » and « Lambert II étendu »
· WGS84: for « Lambert 93 »
The « Advanced » button lets you define the different Lambert parameters for zones not in this list, using the following dialog:
· If you only change the name, a button « Rename » will appear (on the left of the « Cancel » button).
· As soon as one of the other parameters change, a « Create » button appears instead, which lets you add entries to the predefined list. Make sure when doing so, to also give a new name to this entry, as there is no control on the name which can be confusing… Also be aware that there is no way to remove entries using this interface. So limit the different test entries to a minimum.
· The « Paris » button lets you set in a fast manner the Central meridian to the Paris meridian still very much used in Lambert projection.
WARNING: A chart library must only contain maps with
the same projection parameter; otherwise adjustments between the maps will
be approximate, so erroneous. If you want to use
two charts of different projection systems in the same library, you will have
to re-project one of them using the “Reproject chart” function accessible
thru the “Operation” menu.
The Datum specifies parameters that were used by the cartography to reference the chart. It consists of a reference ellipsoid, and of corrections to apply on 3 axes. A Datum name list is available, in which you can choose. You also can enter the numeric values in the appropriate fields. The datum is normally indicated on the chart. For recent charts it is normally the "WGS84 Global Definition". If you don't have the information on the datum, I suggest you stick with WGS84. This datum may be specified as a name, in which case you will have to choose in the list, but it can also be given as numeric values. The ellipsoid is consisted of a Major Axis, and a Minor Axis. These can be given in different forms. In general, you will have the Major Axis and the flattening, where flattening = (Minor Axis) / (Major Axis). Furthermore, for precision reasons, the flattening is most often given than it's inverse (1/flattening). This is the form in which ScanNav expects you to enter these parameters. If you have them in another form, you might have to look for your calculator. Then come the translation parameters Dx, Dy, and Dz, all together forming the Datum.
Once these values entered or chosen from the list, you will have to click on the "Apply" button so as they take effect in ScanNav.
All this is quite complicated, and it is not so easy to know the exact datum the original chart was calculated with. On some charts, you will just find shift information to apply to the WGS84 reference. As an example, on the chart number 6966 of the SHOM you will find indicated: "Positionnement par satellites: les positions obtenus au moyen de systèmes de navigation par satellites rapportées au système géodésique mondial WGS84 doivent être corrigées de 0.06' vers le Nord et de 0.08' vers l'Est pour être en accord avec cette carte", which means in English: "Satellite positioning systems: Positions obtained with a GPS using the WGS84 datum must be moved 0.06' Northward and 0.08' Eastward to agree with this chart" . It is then simpler to just enter this shift information, than to look for the exact datum in the list (Actually this same chart also specifies it is in "European 1950", but this is not always the case.)
So, a new possibility has been added to enter the datum with these shift information’s. For the above example, you will have to choose the WGS84 datum, and enter the following shift information:
· Latitude shift: 0.06 N (N, as positions given by the GPS must be moved North)
· Longitude shift: 0.08 E (E, as positions given by the GPS must be moved East)
This way of entering the datum is much simpler than to look in the list, and gives good enough precision for most charts. This system might also be applied with other datum than WGS84
Important notices:
· Positioning errors due to a wrong datum can vary up to several hundred meters. So it is very important that you make sure you have chosen the right Datum when creating your own charts.
· See also the Navigation.htm - Datum chapter for how to set to the GPS and grid datum parameters.
The following tabs are used to define the georeference grid. In a first step, only 2 points are required. You will have to make sure those two points are not aligned on a same latitude or longitude axis. They only serve for elaborating a georeference grid, which you can manipulate afterwards to fine tune the georeferencement.
Proceed as follows:
· For more precision, use the zoom-in window
· Select the « Points » tab. A combo list lets you choose the point you want to define. You have to define a minimum of 2 points (In a first time, those two points are predefined to arbitrary values). Select point 1 and click on a known point of the chart with the mouse’s Left button to define the first point
· Enter this point’s geographic position in the appropriate fields. Values can be entered in Latitude/Longitude in “Degrees”, “Degrees/Minutes” or “Degrees/Minutes/Seconds” for Mercator projection, or in metric for Lambert and UTM projections.
· Repeat the operation for the second point. Make sure not to place this second point on the same latitude or longitude axis.
· Once the 2 points defined, click on the « Apply » button to validate. The grid is then set up right, and when defining extra points, they will be set with no correction needed if you use the “round position” accordingly (see further).
· In theory, 2 points are enough to reference a chart. But certain charts might not be straight due to age, or scanner skewing. Adding extra reference points, you can correct these imperfections. ScanNav lets you create as many reference points as needed. To add a new point, check the "New Point" box. Than a new point will be created each time you click on the map.
· A 3rd point will let you correct skewed charts, which is the most current deformation when scanning (where meridians and parallels are not perpendicular). Make sure not to align the 3 points. The best is to take 3 points near the chart's opposite corners. Using a 4th point, you can correct a second level of skew, where meridians or parallels are no longer parallel together:
| 3 points |
4 points |
|
|
|
· Other points can be added to fine tune georeference in case of really damaged charts. In this case, you have to spread these points regularly on the chart.
· Adding extra points can be made very easy using the « Round position » option.
When clicking on the chart while this option is checked, the create/modified point is automatically rounded to the nearest geographic position according to the input round parameters. This greatly improves facility to add reference points by for example on crossing of latitude and longitude lines prints in Mercator, or on the Lambert printed cross for Lambert projection, as if the round parameter as been set appropriately you will not have to change the position field. Make sure to choose a round value in ad equation with the chart scale, and with the right Unit (Minutes or Min/A0 for Mercator, Meters for UTM or Lambert). Also be aware that in order for the rounding to work well, you will have to have done a first calibration using 2 or 3 points as described above.
· If you create an extra point by mistake, you can remove it by selecting it in the list and clicking on "Suppress point".
· Clicking on the map without the option “new point” checked redefines the currently selected point.
· To move to a point's location, select it and click "View"
You also have the possibility to work directly with the grid, after having roughly defined two points:
· Select the « Grid » Tab. This lets you manipulate the created grid to fine-tune your referencement.
With this method, you don’t need to make Ultra-Precise referencement in the first go. In fact, the two points you just created are just needed to generate a reference grid, which you can manipulate afterwards when the « Grid » radio button is checked.
By clicking with the mouse’s LEFT button on a meridian or parallel line, you can drag the grid in longitude or latitude moving the line at the position it should be, and you define the meridian or parallel that will serve as reference for the following action (it turns red).
By clicking with the RIGHT button on a line, you move this line to it’s new position, while the « reference » line selected in the previous action doesn’t move, the other meridians or parallels moving proportionally.
You can by this mean adjust the georeferencement visually at the pixel. Nevertheless, this adjustment only stretches latitude and longitude lines in a uniform way, and doesn’t substitute to creating additional reference points in case of distorted charts.
The « Grid Step » button opens up a dialog that lets you enter the desired grid spacing. (You can also use the "Grid" entry of the "Options" menu or the « Navigation » tab of the « preference » dialog to enter the grid spacing)
Some navigation guides contain small portions of detailed maps representing harbor entries or other. Most of the times these maps do not have 2 dots to calibrate, but only one dot and a scale. This georeference method has been added and is reserved for this purpose. Make sure your Datum is correctly set as those small maps often do not specify it, and this can provoke a shift of several hundred meters.
This method is performed in two steps:
· Check the "Reference point" box, and define the known point on the screen by clicking on it. Then enter its coordinates.
· Check the "Distance segment" box and define the know distance on the screen: One first click to start the segment, and another to end it. Then enter its value in the appropriate field.
· Then press the Apply button to validate.
Warning: This functionality is obsolete. It is still present only for historical reasons and will probably be ripped off in future releases. It is strongly recommended not to use it anymore and to prefer added additional reference points to correct distorted charts.
As we saw above, in its first releases, ScanNav didn’t take in account any geodesic system to make its calculations. These were based on an equidistant latitudes Mercator grid. But for large-scale maps, this isn’t the case and you could have a considerable difference between the spacing of latitudes at the top and the bottom of the map, what could give big positioning errors. Now the true Mercator projection is supported, but scanned charts still can be irregular, due for example to folding marks or just to old and scrambled charts.
Grid tool This tool is there to solve this problem. It modifies the chart according to a grid that can be automatically generated and adjusted by the user. It is nevertheless nearly obsolete, referencing with a lot of points being more efficient. This tool should now only be used in certain few specific cases, and will probably disappear or be adapted in future release. This step must be performed AFTER the adjustment and 1st step georeference. Make sure in the 1st step reference that the extreme points (left, bottom, right, and top) of the chart have been correctly referenced. On large-scale maps, make sure you have selected the right projection type (Mercator). If you chose Latitude/Longitude instead, you will see that the intermediate latitudes of the grid don’t fit the exact latitudes. There may also be a non-fit even in longitude, due to distortions of the scanned map. This Tool is going to help you reestablish the concordance by defining your own grid independently of any complicated formula (you don’t need to know the exact geodesic system of your chart, and there are no formula that I know for distortions…) To do so, follow the different steps:
When you select tool number 7, the following control bar appears:
Opens the following
dialog box:
This gives you the opportunity to generate an automatic grid in latitude and/or in longitude. You can for example ask for a grid spacing of 1 Minute of arc, you will then just need to perfect the georeferencement by moving each individual line of the grid to it’s right place.
You can also define individual longitude and/or latitude axes:
· Double-click with the mouse’s Left button on a known point of the map. A dialog box appears with the actual latitude/longitude of this point. You may modify these values, and create longitude and/or latitude axes (use the appropriate check box) that you may manipulate later.
You may move a previously defined axis by clicking on it with the Left button. In opposite to the 1st step referencement, an axis moves independently to other axes.
You may also modify the latitude (or longitude) of an axis, or suppress the axis, using the contextual menu that appears when you click with the mouse’s right button on it.
Once your grid defined, press on this button
to validate the action. Each individual piece of the map is going to be stretched
or compressed so the defined grid fits to a uniform grid.
Clicking on
this button erases the entire grid.
Notices:
· Dialog boxes differ a little if the chart is in the UTM projection
· So as not to be perturbed by the ScanNav’s georeference grid and confuse it with your own grid, temporarily disable it by pressing the « 0 » (zero) keyboard key, or with the "Grid" entry of the "Options" menu, or in the « preference » menu.
· This functionality only corrects the cylindrical projections like Mercator (parallels and meridians must be perpendicular)
· This functionality regenerates all the images of the chart. This has the following consequences:
· All the overlaps of the different scans are eliminated.
· Adjustment between the different scans will then be not so easily retouched.
· The operation can last a time (a progress bar gives you indications on the advancement)
· WARNING: for the demo version, this functionality generates charts with the incrusted copyright notice.
My advice is to backup the chart in a file with the original scans, before performing this step. This will enable people who work with the demo version not to have to re-scan and merge all their charts again, but only perform this last action, if they decide to acquire the official release. You might also find out after a while that an adjustment isn’t so good, and needs to be retouched.
Definition of
the navigable areaThis tool lets you define the area of the chart that will be visible in navigation mode when the option “Hide non navigable area” is checked, the rest of the chart being hidden. This avoids to hide a useful part of a chart with a non navigable part (such as the frame) of an adjacent chart, but still keeping this frame for other various uses such as printing or verifying the georeferencing.
Compared to the “Crop” tool, this tool keeps the hidden area, and lets you define any polygonal area, whereas the “Crop” tool deletes the cropped area, and is limited to vertical or horizontal cropping. The Crop tool is nevertheless still useful to eliminate large Blanc areas that you’ll never need, which saves space on disc and memory.
Defining the navigable area is quite simple. It is the same as for the definition of the danger areas: click on the map with the mouse’s left button on different spots to surround the area. Each click creates a new segment. To finish the area definition, you can either double-click on the last point, or press the keyboard “Entry” key. When clicking with the mouse’s right button you suppress last defined point, and by pressing the keyboard “Esc” key, you abort the area definition.
Once the area is defined, it is displayed with a bold red contour line.
Defining the navigable must be the last step. Indeed, if you add an image that gets out of the navigable area, the area will not grow, so you’ll have to define it again.
When you insert a map already defining a navigable area, the area is affected to the global chart if no other area was defined before. But if an area was already defined, this one will not change.
The goal is to modify chart portions using an external tool to incorporate updates, and reintegrate the changes to the original chart. This is to be done by small portions (limited to an area of 1024x768 pixels, but smaller areas are recommended). The ergonomics will evolve in future releases. For now you can use the following method:
Next step is to modify the chart image using the tool of your choice, with just making sure that you keep it the same width and height, and then save it under the same name.
This window is activated through the "Zoom Window" entry of the "View" menu.
It shows the main window's cursor area at the specified zoom level. This enables you to have good precision on delicate operation such as adjustment or georeferencement without having to zoom in and out continuously. It isn't a pixel zoom of the main window but a real zoom of the origin image. So the chosen zoom level is independent of the main window's zoom level.
By clicking on this window with the mouse's right button, you get a contextual menu the lets you choose the zoom level, as well as to force the window to stay in the foreground (always on top).
This window can also be resized at wish (by pulling on it's frame), so that the zoomed area's size can be changed.
This window is interactive. If you click inside with the mouse's left button, it's just as if you clicked on the corresponding pixel (or rather the fraction of pixel) of the main window. This gives you an extreme precision, without having to zoom in and out on the main window. As the zoom window refreshes permanently to show the cursor region, you have to stop this refreshing so as to be able to move inside it. So when the cursor is inside the area you want to work on, just type on the 'z' key of your keyboard. Then you can move to the zoom window, without it changing, work on it by clicking inside, and when you're finished and want it to restart refreshing, just hit the 'z' key again.
With the « Operations » menu, you can perform several actions on the selected images
· Color Reduction: Lets you reduce the number of colors of the selected images to 16 or 256 colors. Be careful this action is not reversible (no possible Undo). This is useful when you work with images imported at a format of 16 24 or 32 bits. It improves display speed, decreases memory usage, and mostly permits showing the right colors if your display is 256 colors.
· Foreground/Background: Puts the selected images in the foreground or background.
· Original transform: eliminates all transformations made on the selected images (scale, rotation, and adjustment) to show them as they are on disk.
· Reference: defines the selected chart as the reference for calculations (the grid, and position calculations will be based on it’s georeference)
· Adjust to reference: adjusts all the selected charts to fit to the reference: chart are moved and scaled to fit to the reference. Notice: this is done automatically while in navigation mode.
Descriptions of ScanNav charts are stored in files with the « .MAP » extension. They contain the chart’s reference information as well as pointers to raster image files composing the chart. The « Charts » tab of the « Preferences » dialog lets you parameter the raster files characteristics:
ScanNav supports in this version 4 types of raster file format:
· Three standard raster formats: GIF, BMP (4 8 16 24 and 32 bits) and TIFF
· Compressed BMP (4 8 16 24 and 32 bits)
Images generated by ScanNav can be in any of these formats. Nevertheless, it is strongly recommended to use the 8bits Compressed BMP for the following reasons:
· The 16, 24, and 32 bits BMP file formats just increase the disk and memory usage, as well as the performances in certain cases.
· GIF which was the recommend format in previous releases (compressed BMP didn’t exist) is much slower to load and takes a bit more space on disk.
· Standard BMP is faster to load, but takes much more disk space
There are two ways to save a chart:
You only save the information of the « .MAP » file (pointers to existing raster files, plus transformations to apply to these images). Raster images will only be written on disk if:
· They do not already exist (case of a Twain Scan)
· You made essential modifications on them (color reduction, crop or grid stretching)
· You forced ScanNav to save them anyway by selecting the option « Local copy of maps » in « Menu-File-Preference » tab « Maps »
The chart is cut into pieces, and overlapping pieces are got rid of, so as to optimize memory management, loading/unloading, and drawing times while in navigation mode, as well as disk space. In this case, raster images are entirely re-written on disk. Since release 2.0, if the chart is distorted (by entering more than 2 reference points) ScanNav also proposes you to reproject the chart before saving it. Doing this enhances the speed and automatic stitching of charts in navigation mode.
The Width and Height input fields let you enter the basic size in pixels of each raster piece.
The Overlay parameter lets you define an overlay (in pixels) of pieces on each other. It is of no use in ScanNav, and this value should always be 0. It is only meant to eventually export charts to other software that would need such an overlay.
The « borders optimization » check box should always be checked. It enables you, when you save with « Optimize for navigation », to save on disk only the useful parts of the chart, instead of saving the entire rectangular bounding box which can contain blank areas.
ScanNav can generate a thumbnail for each chart. This thumbnail can then be shown in a small separate window that lets you move quickly around the map. (See Using chart thumbnails in the "Navigation" part of this manual). This thumbnail is created automatically when you use the "Export" function with the "Map" format, and on demand if you use the "Save" (or "Save As"). In this case a dialog appears asking you if you want to generate a thumbnail.
« .Map » files can be anywhere on your disk. You must be advised that ".map" files only contain georeferencement information and links to image files. Image files belonging to a chart will be saved in a subdirectory having the same name as the ".map" file, suffixed by « _Files ». As an example, raster image files belonging to the chart « c:\charts\toto.map » will be stored in directory « c:\charts\toto_Files\ ». Nevertheless, if you didn't check the "Local copy of maps" check box nor used "optimize for navigation" to save your chart, the image files can be anywhere on disk at their original place.
So to copy a chart (on CD-ROM for example), you have to make sure to:
· Have checked "Local copy of maps" when saving your chart, or saved it with "optimize for navigation".
· Copy the ".map" file as well as the associated "_Files" directory and its included files.
You can also save an entire chart as a raster image in GIF, TIFF or BMP format with the « Export » menu. This way, you can use them in any imaging software, or even other navigation aid software (let’s stay open!). This way, you can use ScanNav for other purposes such as scanning posters, etc...
Printing is accessible trough the "File" menu. You can either directly print or use the "Print Preview" to visualize on screen the layout of different pages. In both cases the options dialog is the same:
Printer used, as well as it's parameters (Portrait/landscape, paper format, etc…) can be chosen with the button "Configure" that opens a standard Windows dialog.
You can choose to print the entire chart, or just the visible window. Be Careful if you choose "Full map", this represents the full working area of ScanNav, that means all the charts loaded at that moment. This can thus generate an impressing amount of data with which your printer, (and even your PC) will have trouble dealing with, and you'll get an unreadable result if you chose "Fit to Page", or empty out you paper tray if you chose a multi-pages mosaic. So it is recommended that you do this operation in Workshop mode, being sure you only have one map loaded. The "selection" choice is grayed out, as not implemented in this release.
You can choose one or more topics to print among:
· The map image.
· The ScanNav grid: Its step will be the one configured at that moment.
· Routes: This in fact includes all referenced objects: routes, waypoints, tracks and danger areas.
Paging comports several options:
· Fit to page: In this case, the printed topics will be scaled to fit in one page.
In the 2 other cases, printing will be made on a mosaic of several pages.
· To scale 1/XX: here you give the printing scale you want.
· Resolution XXX: Warning, this is not the printing resolution, but the image resolution. If you give the same value as the original scan's resolution, you'll get an output at the same scale as the original paper chart. If you give a higher value the resulting output will be smaller, and if you give a smaller value, it will be larger.
For these last 2 options, you can choose an overlap between pages. This is given in millimeters.
Printing problems: Certain print drivers can cause dysfunction in ScanNav, and certain work better than others can. Some crashes have been reported when printing, mostly with postscript printers under Windows 95/98 (Windows NT has much less problems). So it is important to save your work before you print anything. In case of a crash or a dysfunction try the following manipulations:
· Optimize the chart for navigation: this generates more homogeneous images lighter to mange for the printer.
· Try another driver for the printer: as an example Postscript printers can often be managed in PCL5 mode, and a printer can often be driven by a driver of another similar printer.
· Try to suppress elements to print (for example the grid, or just change it's step…).
· Please report me your dysfunction problems with the more information you can.
In the Demo version, any image generated by ScanNav will be incrusted with a copyright label inside.
