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Archive for the 'printing' Category

Tiling Large Maps For A Small Printer With PosteRazor

If you don’t have a large-format, or even medium-format, printer, you can still print full-size maps by chopping (tiling) the image into smaller subsections, and then taping all those subsections together to re-create the original map in large format. I’ve posted before about several ways to do that generically, and another option that lets you tile georeferenced images to a specified scale. For generic tiling, there’s another option: PosteRazor. Multiplatform (Windows/Mac/Linux), open source, runs by itself (no installation required). A simple 5-step wizard walks you through the process:

  • Select the image
  • Specify the paper size, orientation and margins
  • Choose the amount and orientation of the overlap, the areas that are redundant on the printed sheets to compensate for cutting/taping errors
  • Select the number of pages to print the image on, with a live preview of the print layou
  • Save the tiled images as a multi-page PDF document for printing (it’s very fast at this last step)

Doesn’t have all the bells and whistles of some of the other options, but for a simple tiling operation, PosteRazor is fast and easy.

Tiling And Printing Large Maps To Scale On A Small Printer

A previous post dealt with printing maps larger than a printer’s biggest paper size (Printing Large Maps On A Small Printer). The solution was to split the map image into smaller tiles to be printed separately, to be cut and taped together to form a larger whole. But what if you want to print such a larger map at a specific scale, like 1:24,000? Tiling and printing a map to scale using the options described in that post would be a major pain – you’d have to calculate the correct image size, and then resize the pixel dimensions of the image to get it to print that size. You might even have to add additional blank space to the map edges to get everything to work out.

The program MicroDEM has the ability to automatically tile and size a map image to a specified map scale and paper size, and then print it out on multiple pages for you. Open a georeferenced image in MicroDEM (like a GeoTiff, or a standard graphic format with a world file), and then zoom the image using the 1:1 toolbar button at the top of the map window:


If you don’t zoom to the full 1:1 pixel dimensions, the image will be printed at the original screen scale, which will make the printed version highly pixelated. Next, click on the Print toolbar button:


and select “Print preview & print to scale” from the drop-down menu. You’ll get a window like the following:


In the upper right-hand corner, the current map scale setting is shown, along with the number of sheets of paper that will be required to print the map at the current paper size setting, and the map size in inches printed at the specified scale. At the left, the map image will be displayed as it will be printed on the sheets of paper represented by the rectangles outlined in red.

To change the scale, click on the button that displays the scale, and enter the desired number. To change the paper size or printer settings, click on “Printer setup” and make the desired adjustments. In particular, try experimenting with portrait vs. landscape orientation to see if you can fit a map on fewer sheets of paper.

So if I change the scale of the original map above to 1:24,000, and set the paper size to 11″ x 17″, the window will now look like this:


Click on the “Print to scale” button, and MicroDEM will slice up the map and print it on the specified number of sheets. It can take a while (scratch that, it can take a loooong while) to process the data and print it out, especially for large images; a fast processor and a large amount of memory will help with that. The options described in the post Printing Large Maps On A Small Printer might not be able to print to scale easily, but they do print the tiles a lot faster than MicroDEM does. When the tiles have been printed, cut the blank edges off the appropriate ends of the tiled map pages, then tape them together to create the full map print. Since there’s no image overlap, you’ll have to be careful when trimming them not to remove parts of the printed image, otherwise they won’t fit together exactly.

You can also use this approach along with PDFCreator to generate PDF files of scaled map prints, to be sent to a computer or print service capable of handling larger paper sizes directly.

Advanced Image Mosaicking With Regeemy

If I need to convert a paper map to digital format, and the map is larger than my scanner, I usually scan the map piecewise, and then mosaic the pieces back together into a single image. If I’m lucky, I can get the Photomerge feature of Adobe Photoshop to put all the pieces back together into a single whole, and get good matching at the edges. More often, though, Photomerge can’t get all the pieces to fit together, and I have to match up the sections manually using control points, which is a real pain. But I’ve found a program that automates the process of finding control points and mosaicking map sections, and produces far better results than Photoshop’s Photomerge function. It can also mosaic images shot at different angles and rotations (like satellite/aerial photos) and overlay images to look for temporal changes. If the first image is georegistered, it can automatically georegister the product mosaic image as well.

More after the jump ….

Continue reading ‘Advanced Image Mosaicking With Regeemy’

Better Map Color Schemes With ColorBrewer

When creating a thematic map where color represents different attribute values, there’s always the question of whether the color scheme you’ve selected will look good. and more importantly whether it will convey the information you’re trying to represent to its audience. Trial-and-error is one approach, but the ColorBrewer is a Flash web applet which lets you interactively experiment with different color schemes to see which ones work visually (and which ones don’t). It was created by Professor Cindy Brewer of Penn State University, author of Designing Better Maps: A Guide for GIS Users, and will run in any browser with Flash support.

ColorBrewer doesn’t actually display any of your data – it uses a dummy map of what appears to be counties in the US Southeast to plot different color schemes in sequential, diverging or qualitative fashions. It’s not intended as a data plotter, just to evaluate the visual impact of different color schemes. Inputs include:

  • Number of classes
  • Sequential, diverging or qualitative schemes
  • Mini-legends (pre-built color schemes)
  • Turning map borders, city symbols, road networks on and off
  • Selectable colors for map borders, city symbols, road networks, and the map’s background color.

Here’s a screenshot of the application in action (click on the image for a larger view):

designing better map color schemes with ColorBrewer

In-Browser Web Page Image Capture

A good screen capture utility is useful to have for “snapping” images from programs or web pages, e.g. maps from Google Maps. I posted earlier about a couple of general screen capture programs that run in the background, and can capture images from any program. But if you primarily capture images from websites, there are a couple of handy in-browser utilities for both Firefox and Internet Explorer that let you grab and save an image from directly within the browser.

For Firefox, there’s an extension called Snapper. While the page lists it as being compatible only with Firefox 1.5, there’s a version that I’ve tested with Firefox 2.0 available at this page. After installing the extension and re-starting the browser, a small icon of a red fish (red snapper – get it?) appears in the status bar at the bottom of the browser. To capture an image, click once on the fish (its mouth will open), then click and drag on the screen to select the image you want to capture defined by a red box. It will be saved as a .png file in the c:\Capture directory as a default, but you can modify the capture directory using the extension options screen. Here’s a capture from the Google Maps relief shading site posted about earlier this week:


If you’re using Internet Explorer, there’s an “extension” called IE7Pro that adds not just page image capture, but a whole bunch of other features like ad blocking, mouse gestures, crash recovery, advanced tab management and more. Download and install IE7Pro; the next time you open Internet Explorer, you’ll see a blue “e” in the status bar in the lower right-hand corner. To capture an image of the entire web page, including sections that are currently off-screen but scrollable to, right-click on the “e” and select “Save Current Tab To Image”. You’ll be prompted for the location to which to save the image in PNG format. Right-clicking on the “e” also gives you the option of setting other feature options as well. Even if you don’t need the web page image capture feature, the other features makes this a worthwhile download.

Don’t forget that for many images on the web, use is limited by copyright laws.

Via Webware.

Free Map Symbols

A useful collection of links to map symbols is the Unofficial Arc/Info & ArcView Symbol Page. While some of the links are strictly for ArcView palettes and ArcInfo line and marker sets, a fair number link to graphic symbols and TrueType Fonts useable in any compatible GIS or mapmaking software. Symbol sets cover a wide variety, including roads and highways, geology, and animals. Most, but not all, are free. Also check out the links at the bottom of the page to free clip art resources.

Screen Capture Programs

A screen capture utility is a useful program to have for capturing map images off of web pages, or map displays in programs that don’t offer the capability to save the display as a graphic image. There are lots of them around, but I like mine to be simple, fast, and unobtrusive. My favorite is HoverSnap:


There’s no installation program, just unzip and run it. Clicking on the “Hide” button at the bottom minimizes it to the system tray; clicking once on the icon brings the options window above back. At the bottom, enter the default folder where you want the screen captures to be saved, and a filename to save them under. I recommend checking the “Auto-generate filename …” option, as this will append the date and time to the filename; otherwise, every successive capture will overwrite the previous one. You can save in JPEG, PNG, BMP or GIF formats, and either save at the current resolution or resize the captures to a specific pixel dimension.

When the program is running, pressing the “Print Screen” key saves the entire screen, Alt-Print-Screen saves the active window, and Ctrl-Print-Screen turns the mouse cursor into a crosshair that you can use to select a custom rectangle on the screen for saving by clicking and dragging. As a bonus, the download page for HoverSnap also includes free downloads of some other useful utilities, including a registry cleaner and an IP utility.

For a program with a few more options (more graphic file formats, ability to capture the mouse cursor image, custom capture keys), you might try Gadwin PrintScreen.

Printing Waterproof Maps

If you print your own maps, at some point you may need to take them out in the field, where they’re subject to wear, tear, abuse, spills, weather, etc.. But there are a number of brands of waterproof paper available that are more durable and tear-resistant than regular paper, and also provide some degree of protection from weather and spills. Brands are available for both inkjet and laser printers (caution: if you put some inkjet paper brands into a laser, they melt!). They’re not perfect; while the paper is waterproof, you can still get some bleeding with some inkjet prints if you don’t wipe the water off right away (not a problem with laser prints). And you can’t write with pencil on some of these papers – a waterproof pen is recommended for best results. Do a Google search for waterproof paper, or visit the Waterproof Paper website to see what’s available.