Help:Taking Screenshots To Upload

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This guide is meant to be used for people who wish to take screenshots for the Wiki. For the Wiki page on screenshots, look here.



Apple added the ability to take screenshots into the operating system way back into System 7, at least, and possibly earlier. Since then, little has changed.

Choose Your Screenshot

  1. Because we have the ability to capture a window or icon without capturing the "stuff" behind it (desktop clutter, names, etc.) you must merely have the window open. If you want to take a picture of an icon, the icon must be visible.
  2. Press Command-Shift-4. You will see your arrow replaced by a crosshair. Do not take the screenshot yet, however.
  3. Press the spacebar. Now the crosshair is replaced by a camera. By holding the camera over different windows, icons, and menus those parts of the screen will become highlighted in a light blue. Click to take the picture, or press the escape key to cancel.
  4. Apple has changed the default capture file format over the OS X revisions, and left it largely alone in pre-X. That is...
  • In Tiger, the screenshot is a .PNG file. You may skip to the Uploading section, although you can convert it to an alternative format if you wish.
  • In Panther and previous, the screenshot is a .PDF section. Continue on to the Converting section.
  • In OS 9 and previous, the file is a special Macintosh filetype. Continue on to the Converting section.
  1. If you need to censor your screenshot of anything (name, serial number, etc.) then continue to the Censoring section.


Before converting an image, you should decide what format you want to convert it to. It is important to get the right balance between file size and quality, so that viewers are given a good viewing experience but don't have excessive load times (remember, many users still use dialup modems). There are several common formats to choose from:

  • PNG (Portable Network Graphics) images are the highest quality option as they are lossless. They also have good compression, but tend to be slightly larger than GIFs and JPGs.
  • JPG images vary in effectiveness. If saved in reduced quality they can be very small, however the quality loss involved depends on the image. Photos tend to look acceptable with reduced quality, however many screenshots do not.
  • GIF (Graphics Interchange Format) images should only be used if your image contains only a few different colors (such as screenshots from early versions of Mac OS), otherwise they will look terrible. If they do only contain a few colors, you can get small, good quality files.

If you are unsure which format to use, try saving as a few different formats and see which image has the best mix of quality and file size. It should be noted that the PNG format was designed to replace the GIF format for various reasons, some mentioned above and others too technical for this article. See the PNG article on Wikipedia for more information.


Under Mac OS X, you have a lot of choices for applications to convert images. A few common examples are Preview, Photoshop, and bundled with some computers, GraphicConverter. All will export to most common graphics formats.

In some applications, some settings should be turned off in order to create the smallest files possible. For example, in GraphicConverter, the "Add resource fork" option in Preferences > Save > General should be turned off.

If you are creating a GIF image, GraphicConverter is probably the best application to use. Open your image then choose Picture > Colors > Change to 256 Colors (8 Bit). This will optimise the image's color table so that when it is saved as a GIF (which is limited to 256 colors), the best choice of colors is used. After the conversion, you can save the image.

GraphicConverter is also useful when saving JPGs, as it gives you a preview and can tell you the image's filesize before you save it. This can be useful for deciding what quality to make the image.


Let's say you take a screen shot of the Login Window. This is a wonderful screenshot, and very informative. But what about the names in that list? Better get rid of them, for your own privacy. Or, if you take a picture of a software's about screen that displays a serial number you could be in extreme legal trouble. Anyway, the steps are the same.

  1. Open the file in your favorite photo editor. Photoshop, GraphicConverter, and the Gimp are all acceptable.
  2. Have fun blurring out or removing the material that shouldn't be there.
  3. Save the file in your desired format.


Now, all the hard work comes together.

  1. Open a MacGuides page. On the left side, under the search box is the toolbox. You must have an account and be logged in.
  2. Click the Upload File link
  3. Follow the instructions there! Make sure to give the picture a very descriptive name. If you took a screenshot of a widget, then don't call it "widget001.png". Call it "Calculator Widget.png" or something similar.
  • Although your Mac does not require the use of file extensions, web browsers are not so extension-free. Remember to include the file extension while uploading, otherwise it may not display correctly.