Background Map

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Background map refers to a raster map or OCAD file used as a background. It serves as a drawing template or background image. Examples include scanned draft maps, satellite pictures, orthophotos or relief shadings. OCAD cannot be used to edit background maps.

Order BackgroundMap.png

Scanning a Background Map Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.

It is recommendable to keep with the following two things:

  • Use a grid: In most cases you cannot scan the entire draft map (the background map). You are either limited by Windows (which limits the maximum size of background maps), by the available memory, or by the size of the scanner (A4). In these cases, it is strongly recommended that you should draw a grid on the draft map. In many cases there is already a kilometer grid which can be used. If this does not exist, you should draw a precise grid of vertical and horizontal lines (perhaps at a distance of 10 cm). Then the scanned pieces can be easily joined together in OCAD.
  • Resolution: It is recommendable to scan the map with 300 dpi.

OCAD supports only WIA compatible scanners. Click Scan in the Background map menu. The Scan dialog opens.

ScanDialog.png

Choose the extent and click Scan. You have the option to save file file in jpg, bmp or png file format. Then the scanned background map is opened.

Open a Background Map Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Course Setting.

Choose this command from the Background Map menu to open a background map which is displayed as a background picture on the screen. OCAD can open BMP, GIF, PDF, PNG, TIFF, JPEG, JPG2000, 32-bit JPEG and TIFF files. In addition, OCAD maps (*.ocd) or Encrypted OCAD maps (*.eocd) can be loaded as a background map, too. The Open Background map dialog appears. Choose a file and click the Open button.

Note: In the OCAD Starter Edition, OCAD (.ocd) and Encrypted OCAD Maps (.eocd) are only available to use as a background map in course setting projects.

hint OCAD 2018 can load only encrypted OCAD files exported from OCAD 2018. Encrypted OCAD 10, OCAD 11 or OCAD 12 files are not compatible with OCAD 2018.

hint OCAD loads the background map hidden when pressing the Shift key while clicking the Open menu item.

Use a Georeferenced Raster Map as Background Map

If your map is georeferenced and you want to use a georeferenced map as background map:

  1. Select the Open command in the Background Map menu. The Background Map dialog box opens.
  2. Select a file and click the Open button.
  3. The Background Map (Georeferenced) dialog appears and shows the georeferencing of the selected map.
    • Select the New Offset option to create a new map offset. The center of the map will be moved to the offset you typed in the Easting and Northing Offset fields and rotated with the angle entered in the Angle field. In addition, the scale can be changed.
    • Select the Existing Offset and Angle option to leave the map as it is. The background map will be placed at the correct position with reference to the existing map offset and angle. If you choose this option, the background map may be placed outside the map range. In this case, an error message will appear.
    • Select the Transform from other coordinate system option to transform the background map from another coordinate system when opening the aerial image.
    BackgroundMapDialogGeoreferenced.PNG
  4. Click the OK button to finish.


hint - Click the Entire Map button to display the entire background map.

- The Draft Mode option in the View menu can be used to dim map objects and the background map itself.
- Ocad files can also be loaded as background maps.


Use a Non Georeferenced Raster Map as Background Map

If your map is georeferenced and you want to load a non-georeferenced map:

  1. Select the Open command in the Background Map menu. The Background Map dialog box opens.
  2. Select a file and click the Open button.
  3. Enter a resolution for the background map (if a raster map is loaded) and click the OK button.

NonGeoreferencedRasterMap.png

The background map is displayed at the center of the current drawing area. The raster map (background map) now needs to be adjusted with the map (Adjust a Background Map). In other words, it needs to be referenced with the map coordinate system.
hint You can scan a raster map to use it as a background map directly in Ocad: Select Scan in the Background Map menu and then choose the Acquire submenu. Your scanner's dialog box will open (Scanning a Background Map).

Infrared Images

OCAD supports 32-bit infrared tiff images. When opening an infrared image Ocad shows the following message box:

MessageBoxInfraredImage.png

Click Yes to show the background map as false-color image using the infrared, red and green spectral bands mapped to RGB.

InfraredImageFalseColors.png

Click No to show the background map as true-color image.

InfraredImageTrueColors.png

Error or Warning Messages

Error Message Not enough memory for the background map

This error message appears if Windows cannot provide the memory needed to load the whole background map. For uncompressed background map files the size of memory needed is about the file size. Compressed background map files have to be expanded in memory and therefore need more memory than their file size.

hint If Ocad 64-bit version is used, background map files bigger than 2.1GB can be loaded.

Error Message TIFF variant not supported

This error message appears if the TIFF variant is not supported by the current version of OCAD.

Error Message This TIFF file contains tiles. OCAD does not support TIFF files with tiles

This error message appears if the TIFF contains tiles which OCAD doe not support. Please convert this file into an untiled TIFF format.

Error Message Compression type not supported

This error message appears if the compression in the opened TIFF file is not supported by the current version of Ocad.

Warning The background map is geo-referenced in the scale 1:x but the open map is in the scale 1:y

WarningOpenOcdBackgroundMapInOtherScale.png

This warning appears if the OCD background map is geo-referenced and has an other scale than the currently opened map. Ocad opens the map but ignores the georeferencing (no scaling and no offset) and uses the paper coordinates.

To avoid this warning message, open the OCD-File you want to load as a background map and use the change the map scale function.

Limitations for Georeferenced ocd Background Maps

OCAD supports different real world offsets and real world angles. The offset and angle can be set in the Set Scale and Coordinate System dialog. In some cases, OCAD has a redrawing problem with different real world angles.

Open pdf as Background Map

OCAD cannot load pdf files as background maps. OCAD uses the software Ghostscript to convert the pdf to jpg and load this jpg file.

To open pdf files you have to install the software Ghostscript and set the Ghostscript path in the OCAD Preferences.

Example:

GhostscriptFilePath.png

  • Open pdf as background map

BackgroundMapOpenPdf.png

  • Ghostscript converts the file to a not georeferenced jpg. So you have to adjust this background map. The loaded jpg images is in the list of the background maps.

BackgroundMapOpenPdfLoadedJpg.png

Adjust a Background Map Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Course Setting.

Choose this command in the Background Map menu or press the F9 button (Shortcut by default) to adjust the background map. This command is active when one or more raster background maps are loaded.
If more than one background map is loaded, you will have to choose a map in a dialog box:
BackgroundMapAdjust.png
hintBackground maps from online WMS are not shown in this dialog box.

A background map can be adjusted to the grid or to the map. A grid on the background map makes it easier to adjust it. The grid crossing points can be used for the adjustment (however, any points can be used).

It is possible to use 1 to 12 points for the adjustment. After choosing the Adjust command the cursor changes to a cross line with a black and white squared pattern. You are now in the Adjust mode. Do the following steps for each adjustment point:

  1. Mark a point on the background map (e.g. grid point or a surface reference point) by clicking it.
  2. Mark the same point on the map by clicking it.

In the bottom left part of the Status Bar you can always see, which point you have to mark at the moment, when you are in the Adjust mode.
When having adjusted enough points, execute the adjustment by pressing the Enter key. The background map is rotated and stretched to get the best fit for the adjustment points.

If the adjustment is not good use the Undo function to cancel the new adjustment.

hint - If the size of the raster map corresponds exactly with that of the map scale and has not been rotated, it is possible to adjust it with the map using a single point pair. OCAD will correctly reposition the raster map without changing the scale or angle.

- If the raster map is contorted, rescaled or rotated, you will need to use between 3 and 12 point pairs to adjust the image with the map. OCAD repositions the raster map by transforming it (affine transformation) and adjusts the scale and angle accordingly. The point pairs should be distributed equally across the map.
- If the adjustment point pairs lie outside of the drawing window, you can move the map section between the adjustment point pairs during the adjustment process.

Error Adjustment points too close: When using several points for adjusting a background map, the outermost points must be separated by at least 2 mm on the background map.

Note: OCAD Background Maps cannot be adjusted. The Georeferencing is used to place the map or, if the map is not georeferenced, the origin of the background map (middle of the map, point (0/0)) is displayed on the origin of the current map.

Once you have completed the map adjustment, the raster map can be saved as a georeferenced raster map. The advantage of this is that the raster map will be loaded in the correct position the next time it is opened.

AdjustBackgroundMap.gif

Export Georeferenced Raster Map

To save the raster map as a georeferenced raster map:

  1. Select the Export command in the File menu.
  2. Select a desired raster format (TIF, JPG, GIF or BMP)
  3. Select a Resolution (300 dpi is recommended for printing maps)
  4. Select the Create World file option
  5. Click the OK button.

Hide all Background Maps Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Viewer.This function is available in OCAD Course Setting.

Choose the Hide All command in the Background Map menu or press the F10 key (Shortcut by default) to hide all background maps temporarily or make them visible when they are hidden. This command is active if one or more background maps are loaded.

If you want to hide only single background maps, choose the Manage command from the Background Map menu.

Manage Background Maps Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Viewer.This function is available in OCAD Course Setting.

Choose the Manage command from the Background Map menu to set options for displaying and printing the background maps. The Manage Background Map dialog box is displayed. This is a non-modal dialog box. It is possible to switch between the dialog box and the map window without closing the dialog. Changes are directly updated on the map.

ManageBackgroundMap1.png

In the Manage Background Map dialog a table is displayed. In this table all loaded background maps are listed. The table consists of the following columns:

Visibility optionsSpace.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Viewer.This function is available in OCAD Course Setting.

  • V (Visible): You can make a background map visible or hide it by clicking the corresponding cell in this column. An eye icon in this column means that the background map is visible.
hint To hide all background maps temporary use the Hide All command in the Background Map menu.
  • F (Visible in Background Favorites view mode): You can make a background map visible or hide it in the Background Favorites by clicking the corresponding cell in this column. An eye icon in this column means that the background map is visible in the Background Favorites.
  • Dim: In this column you can enter a value in percentage to make the background map appear brighter, i.e. to dim it. 0% means the background map is displayed in its original colors. 100% means the background map appears completely white. Dimming is used to get a better distinction between the background map and the map.
  • T (Transparent): If more than one background map is opened you can set them transparent so that both are visible. Activate this option by clicking the corresponding cell in this column.

Assign to Spot Color Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.

This feature is used in a special production process, namely to update old hand drawn or scribed maps. The printing plates for each spot color are scanned (black and white or gray-scale) and then used as background maps. When such a background map is assigned to a spot color, it is displayed with this color. In addition, when the Spot Color View is activated the background map is displayed together with the corresponding spot color.

Visit the Define Spot Colors page to learn more about spot colors.

Note: This feature is intended for black and white or gray-scale background maps. If a color background map is assigned, the resulting colors are undefined.

Blockout Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.

This column is labeled with a B and is only available for raster background maps. Click a cell in the Blockout column to use the corresponding background map as a block out mask.

If you have several black and white or gray-scale background maps which are transparent and assigned to a spot color, you can use this function to hide some background maps in a certain area of a different background map.

In the following example, there are four black and white or grey-scale background maps loaded. Each background map was assigned to a spot color. There are the purple, the black and the blue lines. The fourth background map was assigned to the yellow color. The Manage Background Map dialog looks as follows:

ManageBackgroundMap.PNG

The yellow background map is used as a Blockout mask. The result looks as follows.

Blockout.PNG

The black and the purple background maps are hidden behind the yellow areas when using Blockout. The blue background map is drawn over the yellow areas because it is over the blockout mask in the order of the background maps.

File name Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Viewer.This function is available in OCAD Course Setting.

The file name of the background map is displayed in the File name column.

hint The absolute path is shown if the background map file is in another folder than the map. However the relativ path is also saved if the background map is on the same drive as the map file. The background map is still found if the map and background map files are moved to another folder but the relativ path keeps to be the same.
hint Remove and re-open (not relink) the background map if the relative path does not work.

I (Information) Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Viewer.This function is available in OCAD Course Setting.

Click on the BackgroundMapsInfoIcon.png information icon to get more information about the corresponding raster background map. The Background Map Info dialog box appears with additional information. The given information varies depending on the file type.

Info for raster background map:
Info for raster background map

Info for OCAD background map:
Info for OCAD background map

If an encrypted background map is load then a BackgroundMapsInfoLock.png lock icon is displayed in the information column.

ManageBackgroundMapEncryptedIcon.png

Click on the BackgroundMapsInfoLock.png lock icon to get more information about the encrypted background map.

ManageBackgroundMapEncryptedInfo.png

WMS

Background maps from online WMS are displayed with light blue color.

BackgroundMapsManagerWms.png

Other Functions Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.This function is available in OCAD Course Setting.

  • Move Up: Click the Move Up icon to move the selected background map one line upwards. Background maps which are listed in a upper position in the Manage Background Map table are diplayed in the foreground.
  • Move Down: Click the Move Down icon to move the selected background map one line downwards. Background maps which are listed in a lower position in the Manage Background Map table are diplayed in the background.
hint The selected background map can also be moved up and down with drag and drop on the file name column.
hint OCAD loads the background map hidden when pressing the Shift key while clicking the Open butten or menu item.
  • Relink: Relink background maps to another directory.
  • Remove all: Click this button to remove all background maps. This command does not delete the background map files.
  • Remove: Click this button to remove the selected background map. This command does not delete the background map file.
  • Close: Click the close button to quit the dialog.

Web Map Service - WMS Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.

Visit the Web Map Service page to get some information about this function.

Online Map Services Space.PNGThis function is available in OCAD Mapping Solution.This function is available in OCAD Orienteering.This function is available in OCAD Starter.

Visit the Online Map Services page to get some information about this function.

Bulk Export Space.PNGThis function is available in OCAD Mapping Solution.

This function is only available on request. Visit the Bulk Export page to get some information about this function.

Download Georeferenced Satellite Images

Visit the Download Georeferenced Satellite Images page to get some information about this function.


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