Earlier this week I discussed the issue of
fuzzy stills rendered by iMovie. Bruce Gee, Big Cheese of
GeeThree, makers of the aptly named Slick Transitions & Effects iMovie plug-ins read my musings and piped in with a few pithy comments of his own. I’ll let Bruce carry on from here. He writes:
From my knowledge of how iMovie works, here are some reasons why I believe we all see fuzzy images:
The preview is really just a proxy of what gets rendered, the preview in iMovie gets drawn without regards of the internal format of the project. When rendering does occur, it should use the same rendering path as the preview, so things should look the same—right?
Here are some reasons why things may look fuzzy when viewed within iMovie after it has been rendered. Most of these items apply to .dv projects.
- DV codec. Compression degrades image fidelity when the colors are extremely bright or dark (outside of the TV safe range). So a pure white title will not look good, and a completely bright yellow or red can look downright awful. This is also true for still images with 100% white or black portions in it. So select the color of your title carefully.
- Non-square pixels vs. square pixels. The common DV format uses non-square pixels, and these need to be converted to square pixels for display on a computer screen. But don’t worry, the final output will go to non-square pixels.
- Scaling. Most computer screens are quite large these days. If the video window area displayed in iMovie application is larger than 640X480, the rendered clip is getting scaled up. The preview renders at the full size of the Preview window (and without compression), which in most cases is larger than 640X480. It probably has something to do with the Playback Quality preference in iMovie, but I haven’t quite figured this option out.
When you combine all of these factors together, things can look blurry within the iMovie application. But in most cases, when you output to tape or DVD, things will look much better than what you see in iMovie. Any other application that you use to create a DVD is subject to these same limitations—iMovie is just guilty of displaying the rendered video before it goes out to tape or DVD.
Interesting test: Drag a clip from the iMovie timeline to the desktop. Open that clip in QT Player and turn on the High Quality option for the video track (may require QT Pro). Compare how this clip looks compared to iMovie. You should see there is a difference of how iMovie displays things and the underlying data.