Zooming and panning; two of my favorite things about prezi... but...

Zooming and panning during a classroom presentation can quickly go the way of the Blair Witch project... if you're not careful.

I'd like to offer a set of suggestions for how to keep your audience dramamine-free.  

Disclaimers: These suggestions are based on a combination of intuition and impromptu polls of grad-student preferences during live presentations. The younger your audience, the less important these tricks.

1. The easiest solution:

You can get away with almost any kind of navigation between any kind of content if you don't go full screen. Leaving a static border around your prezi seems to help keep folks' equilibrium intact.

---Follow-up tips for 1.---

For fine-grained control over how much of your projected screen size is taken up by your prezi, resize your browser window using ctrl+roll (pc). This allows you to make the border around your prezi as thick or thin as you like in fairly small increments. This browser resize trick works for prezis you embed in external sites as well as for prezis viewed at prezi.com... you do of course have more control over your 'border' color on an external site.

Prezi offers fine-grained control over their embedded player size when you choose to embed a prezi in an external site. So, you can skip the ctrl+roll and also to make great 'prezi-backgrounds' that appear for all viewers.

2. Centralized zooming

Place images and text along the edges of slides. Please pardon any micro-managing... Copy your first slide, shrink it to appx 1/10th, and then place the shrunken copy into the center of the first slide. Path steps should be between big slides and the slides in their centers. (you'll likely only be able to make a path 4-6 steps deep with this type of central zooming; use other tips to break out of the 'bottoms' of these paths)

3. Cornerstone objects: "2-d" and "3-d"

By "Cornerstone objects" I mean images placed inside a prezi that provide visual anchors for audience members during navigation.

Here again, simpler is better.

A great "2-d" cornerstone object is an image consisting only of thick horizontal lines that are stacked vertically; those lines end up functioning like race-tracks between frames/slides. (You can draw those lines in prezi if you like.) I'd suggest placing frames/slides within the vertical boundary of a single line and separating each frame by at least 3 frame widths or by whatever distance is necessary to ensure that no two frames are visible during navigation. This way, navigation direction is communicated to your audience and your audience can be soothed by the smoothness of motion along a plainly delineated path. Works best with text-only content and succinct, unfilled slides.

I've only ever used one "3-d" image as a cornerstone object, but audiences liked it. That image was a "ball and stick model" of a molecule. In each of my slides, the molecule took up most of the screen and my text was placed between two outer atoms. Navigation between slides took advantage of the 3-d-ness of the image by zooming in between different sticks of the model... at each zoom level, the slides were laid out the same. I found that zooming past a simple 3-d image is easy for an audience to stay balanced through and likewise for  zooming in on or away from a simple 3-d image.

4. Speed control with separation and size ratios

If you simply must navigate from side to side or up and down, and if you've just got to have high-content-density slides, fine, be that way... one way to get away with it is to place your slides really far apart.

When prezi navigates across large planar distances it does so quickly and with a nice zoom sequence. Admittedly, this fast motion ends up being a 50/50 fix... sometimes the sudden motion is off-putting, but other times, getting a slide in or out of focus quickly is smoothest way to jump around.

5. Slide layout relative to navigation path progression.

"First to go, last to appear."

Another way to make left/right/up/down navigation comfortable for your audience is to place each slide's content along one of that slide's edges or corners. Which side? Which corner?

Well that depends on path orientation. If, for instance, your first navigational step will begin at slide A and end at slide B, then you're best off placing content along the left edge of slide A and along the right edge of slide B.

By doing so, you ensure that the content of slide A crosses very little of the screen when 'flying-out' and that the content of slide B crosses very little of the screen when 'flying-in;' reducing opportunity for blur.

This beneficial effect can  be enhanced with the incorporation of depth between otherwise left/right paths.

Three general closing thoughts for maximizing audiene comfort during navigation:

Your prezi is more disbalancing for your audience than for you when they don't know where it's headed next. I mention this to explain why others might react poorly to your navigation and as a suggestion that you make clear within your prezis how your paths will progress from frame to frame.

Any Blair Witch effects seen on a small-screen will be multiplied when you project your prezi onto a large screen.

Frame content density and audience comfort during navigation are directly related... keep your slides clean and succinct... as an added bonus keeping slide content density low also makes for more effective presentations (if powerpoint research is anything to go on).

Examples upon request.

Ed J