Image Size and Resolution

over stretched image

Think this image looks good? Click on it to see it actual size. Yikes!

I made a presentation at Ohio TESOL last week about how to make better PowerPoint presentations.  I’m going to add the audio to my slides by the end of this week (currently, you can only view the original slides sans audio).

Overall, the presentation was very well received.  In fact, I even inspired some people to overcome their fear and give PowerPoint a try.  One such brave soul emailed me the following question about blurry images, which I think is worth sharing here.  It’s a problem that many beginners face when adding images to PowerPoint presentations as well as print documents.  You won’t be an expert until you can fix it.  My response follows.

I loved your presentation last week on PowerPoint.  Being technically challenged, pp has never been at the top of my list to try.  But, after listening to you last Friday, I have put together a small presentation for a listening and speaking one class.  My question is…After I paste and stretch photos from Flicker, they are blurry.  I realize it is probably a simple click, but I cannot find it.  Please help!

I’m glad you enjoyed my presentation and I’m glad you’re diving in  and trying things out in PowerPoint.  I think this is a really good way to learn this technology.

image stretched 900%

Stretching an image to 900% of its original size will result in a blurry or pixelated image.

The issue you’re dealing with is a common one.  It has to do with the size and resolution of the original image you’re trying to add to your presentation.  When you are in PowerPoint, double-click on the image you’re working with to pull up the “Format Picture” menu.  Choose the “Size” tab at the top to see if you’ve stretched your image past it’s original size.  If the height or width under “Scale” is more than 100%, you will probably experience some blurriness or you will start to see all of the pixels that make up the image.  (To really see this, try using a really small image from a website and stretching it to fill your entire slide.  It will get really, really blurry and pixely.)

flickr picture

Click on "all sizes" to find larger versions of images in Flickr.

So, that’s the problem, but what’s the solution?  Well, you need to start with larger original images.  Once you find an image in Flickr, you will see an “ALL SIZES” button right under the title of the picture.  This will take you to the original picture and often give you several different size options.  By choosing the original, you can usually find a version large enough that you will be able to stretch it to fill your slide.  I suggest you double-check after you stretch it though (double-click again to pull up the Format Picture menu) because if it’s more than about 110% of the original size, your picture may look stretched when projected onto a screen even if you don’t notice any problems on your computer.

Something else to consider is the file size of the picture you use.  If you just need a small picture, try to avoid using the largest size.  Using larger pictures increases the size of the file for your final presentation.  While finding room on a hard drive usually isn’t a problem for new computers, on some machines PowerPoint can get bogged down and run slowly if many large photos have to be loaded for every slide.  So, if you only need a little picture in the corner, try using a smaller size image.

I hope that’s pretty clear.  Give it a try and let me know if you’re still having trouble.  Incidentally, I hope to upload an updated version of my presentation complete with audio in the next couple of days.  Watch for it here: http://www.slideshare.net/eslchill

Advertisements

Leave a comment

Filed under Projects

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s