Exactly what is INSIDE the video you are editing?
Codec & Format information, with 2 links inside for you to read http://forums.adobe.com/thread/1270588
Report back with the codec details of your file, use the programs below... A screen shot works well to SHOW people what you are doing
https://forums.adobe.com/thread/1070933 for screen shot instructions
Free programs to get file information for PC/Mac http://mediaarea.net/en/MediaInfo/Download
Does your video use a VARIABLE Frame Rate or a Constant Frame Rate?
Also, you need to post details about your computer and the version of Premiere Elements you are using
Timeline rendering does not fix issues. It is a preview feature that gives you the best possible preview of what you have as evidenced by the Edit area monitor playback of the Timeline content. It is a means to catch a problem sooner than later.
The answers are in the details. Your issue may reflect an issue in previewing or an overall project issue.
Quick way to gauge which way this is going...export the Timeline to a file and determine if you observe the problem before and after export.
If it is the same before and after, then the important information exchange includes some of what John as already mentioned
1. Properties of source media - video audio readout programs are good for this purpose, but the information may be gotten by telling us the brand/model/settings of the camera that recorded the video. (including file extension). This information has added important if you are working with cell phones, iPad, or other devices that record with a variable frame rate.
2. Project settings as confirmed using Edit Menu/Project Settings/General - with Premiere Elements 11, 12, or 13 you may be working in a 1080i project when you have 1080p at no fault of your own.
3. The nature of the edits to the now rendered Timeline content that is presenting poorly at previewing in the Edit area.
Please review, consider, and give more details for us to help you. We can go at whatever pace you want to in the troubleshooting. If any questions or need clarification, please do not hesitate to ask.
I'm having a similar problem...very slow, jerky video on transitions and effects. I'm using mostly still images, so don't think codecs, etc. are an issue:
- I used 1920x1440 setting thinking it might result in better quality in the end, but maybe this is the problem (files too large).
- Rendered images/effects are still jerky, and actually don't seem to make much difference.
- I have a separate drive for scratch/rendered files
I'm thinking of starting over with a smaller project setting (DV 720x480)...
I'm not aware of a 1920x1440 setting for a project. And starting a new project at 720x480 would only be a solution if you're trying to edit a specific type of video.
But if you'd like to troubleshoot what's going on, I'd encourage you to start your own thread so we can address your specific issue.
Be sure to tell us there which version of the program you're using on what operating system and what model of camcorder your video is coming from and what format and resolution the video is.