For more general Q&A and work arounds for the bug below, check out my:
FAQ for Adobe Premiere
Update [Aug. 24, 2002]
With the release of Premiere 6.5, Adobe has fixed this bug. Also fixed is the blurring of footage when applying certain filters. I have put together a ZIP file that contains 2 project files to show what is going on. One file is for opening in Premiere 6.0x and the other is for opening in Premiere 6.5. Scrubbing the time line will look the same, but a render preview or final render with show the differences. Also note that the titles in the 6.5 project are using the new 6.5 titler. Very nice!
Premiere_Aspect_Tests.zip [307.5 KB]
How Adobe Premiere 6.0x handles pixel aspect ratio of footage.
Adobe Premiere now has the ability to differentiate between footage with varying pixel aspect ratios. This includes DV, DV widescreen, Anamorphic etc. You can even add your own by adding a line to the Interpretation Rules.txt file that is located in your plug-ins folder.
The problem I have come across is that Premiere only adjusts your footage (video or still) to square pixels. This is fine if your final output will be viewed on a computer, but can create real problems if you output to DV which has a 0.9 pixel aspect. When you render to a format that has non-square pixel aspect, what you see scrubbed on the timeline is not what you see as your final render!
Below is an animated GIF that shows the monitor window for three different images with three different pixel aspect ratios. Also below is a diagram show what I believe to be the logic that Adobe Premiere decides how to handle the different images. The animation shows the scrub before and after a preview is done. Note that when you preview on the timeline, the movie is rendered to your aspect settings. When you scrub after a preview file is built, (the red bar changes to blue in the timeline) you actually scrub through the rendered file. Premiere 6 adjusts the rendered file to square pixels on your monitor.
Please note that each image has "maintain aspect ratio" turned on and the project settings is set to DV/D1 pixel aspect ratio 0.9.
A few notes about what is going on above
- Since the output pixel aspect is set to 0.9, footage that is 0.9 renders correctly, the footage and the output pixel aspect matches
- All the footage renders correctly when scrubbing the timeline if no preview is done, this is because Premiere is converting everything to square pixels, which is the same as the output type (your screen uses square pixels)
- The DV Widescreen footage is reduce in size top-to-bottom for scrubbing without preview. The final render, the footage is reduce top-to-bottom, but not the correct amount.
- I have not investigated the actual algorithm for the different pixel conversion and resizing. Premiere does a good job at resizing the video, it just resizes it to the wrong size!
- If you turn off "maintain aspect ratio", the render will be done correctly, but this is only because the footage and final output are to be 4:3. If you put an arbitrary image on the timeline (such as a nice portrait digital image you took with your digital camera) and have maintain aspect ratio turned off, the image will not be rendered correctly if the output is to be none square pixels.
The ability for Adobe Premiere to handle non square pixel aspects is a major feature, and a feature that every review I have read says is there. The problem is that it is not fully implemented or is buggy. I am not sure which it is, but lets hope that Adobe corrects this one way or the other without having to purchase an upgrade.
I had never called Adobe tech support before I discovered this. I am usually one who will figure something out or the answer can be found online through various forums. When I did call, the phone was answered pretty quickly (after getting through the menus). The only problem I had was that the person on the other end wanted me to follow a different workflow (crop to 4:3 in Photoshop, or change the canvas size to 4:3 size). This is what that I have been doing for years. In past versions of Premiere, this would be how things had to be done. I could never get across the idea that a new work flow could be used in Premiere 6 if things were working as they should.
I was finally contacted by the Premiere "guru" at Adobe who said that what I have found (above) is correct, but there was no word of any fix or tech note. I never heard from Adobe again!
Footage used in animation above:
640x480 - square (1.0) content (65.7 KB)
720x480 - DV 4:3 NTSC (0.9) content (70.2 KB)
720x480 - DV 16:9 NTSC (1.2) content (86.3 KB) - must be set to DV widescreen in Premiere
If you have any comments about the above notes, please let me know.