Crop the image.

Go to EFFECTS|ZOOM IN and drop that effect onto the clip or the effect track.

Click the KEYFRAME button, and note the code at the top of the window.
Move the scrubber to the spot where you want the freeze and note the width/height numbers at the left.

Click the diamond icon for both width/height to set two keyframes.

Move the scrubber to the end of the clip and manually change the width/height numbers to those that you noted earlier.

Hi borgus1,
Thanks for the tip. Your suggestion allows much more control over the zoom in feature and overcomes the fixed aspect ratio that is required to be maintained in video crop. However, PD12 does not behave well when the frame rate of the video does not match the standard frame rates. In my case the Hero 3+ captures 4K video at 11 fps and PD12 does not allow you to choose a non-standard frame rate for the timeline. Although the video play reasonable well in the timeline when you try to overlay it with the zoom in feature you mentioned the preview windows goes black. I have notice this on several GPU enabled effects.

Anyway thanks for the tip.

Quote: Although the video play reasonably well in the timeline when you try to overlay it with the zoom in feature you mentioned the preview windows goes black.

Disable Open CL, under EDIT|PREFS|HARDWARE ACCELERATION.

Or, don't overlay the clip. Instead, drag the effect to the effect track. It should play. Click EFFECTS and make the same adjustments as suggested earlier.

Unchecking the open CL did fix the problem with black preview screen. Thank you. Also, after playing with Zoom In feature, I realized it is best to lock the aspect ratio to produced a natural zoom. The one down side to this feature is that you don't seem to be able to direct the zoom to point as you can with video crop. I want to zoom in on an object that is not exacting in the center of the clip as shot. I could easily do that with video crop (minus the benefit of keyframes), but how to do it with zoom in feature was not obvious to me.

Double-click the clip on the timeline or select it and click MODIFY. Click the MOTION tab, then the top-left X choice.

Set keyframes for SCALE and MOTION at the beginning of the clip. Move the scrubber and click the diamonds to set two new keyframes. Drag the image handles in the preview window, to see if the desired effect can be achieved.

Unfortunately, I was unable to achieve the effect I desired using a combination of scale and motion and combining that with zoom. I tried several combinations, e.g. scale and motion to place the object I want to zoom in on in the center of the screen and then apply the zoom or zoom on the object and then apply the scale and motion. All resulted in a very small video in the preview screen or zooming in on the center of the original video clip, but not the off-center object of interest. I do appreciate the time you have spent responding to my inquiry. The video crop is very easy to execute and achieves the desired effect, but can not be don with the precision with respect to the time codes of the video clip. Adding time code to the video crop function would be a nice improvement in the next release. With much appreciation for your help.

Note that the timecode window tracks the scrubber. But yes, this is a zoom to the center of the image.

Thank you for the movie. It is instructive and confirms that I was interpreting your instruction correctly. It might be possible to achieve the desired effect of zooming in on an off center point in a clip with some trail and error using the method you outlined. You answered my original question and provided valued insight into workings of some of many features in PD12. Thank you.