Exporting from Powerpoint to the Wiki

Most images for Species-ID should be provided in the JPG or PNG formats. Occasionally, multiple images have already been arranged - often together with numbers or scale bars - into a composite image. If this has been done in Microsoft Powerpoint, a typical problem is that saving a Powerpoint slide to the jpg or png formats will produce relatively low resolution images. To create higher resolutions, two methods have been successfully tested. The first method is simpler, but may occasionally lead to artifacts; the second method is more indirect, but by shifting the rescaling into the PDF-creation process may avoid artifacts.

1. In the print options, set the page size from typically "Letter" or "A4" to a very large size (e.g. "A0 Oversize"). If the option for such a large size is not available on your computer, you may have to install a printer driver for a poster print such as the HP DesignJet (it does not matter if you indeed have such a printer of not).

   One disadantage of this method is that changing the page size forces Powerpoint to rescale all elements on the Powerpoint slide. Given the very large amount of rescaling, this can occasionally lead to artifacts like a gap appearing between previously fully adjacent images.

2. The second option requires to have Adobe Acrobat and Distiller available (tested with version 8). It first creates a PDF, then saves the PDF as an image:
   • In Powerpoint (we used Powerpoint 2007), print the slide to PDF. In the print dialog, select the "Adobe PDF Converter" as the printer and click the "Properties" button on the right side of the printer driver. In the following Adobe PDF dialog select "Default Setting = High Quality" and again a very large paper size: "Adobe PDF Page Size = Oversize A0". Close the dialog box with OK. Back in the Powerpoint print dialog select "Current slide", tick "Scale to paper", and "High Quality", and print the slide to create a PDF file. Note: in this method, the large paper size is only set inside the PDF distiller, not anywhere in Powerpoint; only this avoids the rescaling problem.
   • In a PDF reader (we used Adobe Acrobat) select in the menu "File, Save As", at the bottom "Save as Type = PNG", click on Settings to the right and select under "Conversion" "Colorspace = Grayscale" or "Colorspace = Color RGB" or and "300 pixels per inch". Leaving the Conversion setting on "Default" may result in a grayscale image being saved as a rasterized monochrome image, which is generally of low quality.

Feedback on these procedures is highly welcome!