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Screen Aspect Ratios and Pixel Aspect Ratios
Hello everyone and thank you for indulging some very basic questions that have probably come up before. I just need a little help to nudge me in the right direction. I have issues with screen aspect ratios and pixel aspect ratios.
I have created an opening title sequence by importing images created in Photoshop, which are square pixels. My immediate usage is a museum documentary presentation on a 4:3 CTR TV. I may want to submit it to a local film festival later so something wider than 4:3 is desirable. I selected a screen aspect of NTSC DV widescreen 720 x 480. I had the pixel aspect ratio set at D1/DV NTSC Widescreen 1.2. I did not notice distortion of my images until I began struggling with my second problem, and read Rick Gerad’s article at:
https://library.creativecow.net/articles/gerard_rick/pixel_madness.php
I’m a little confused right now. If I set the pixel aspect ratio to square the images look fine in the comp window but will I have distortion in the rendered file?
Now, the other issue comes when I go to edit my entire video. I am a beginner here and have only basic Mac programs (iMovie, DVD) and AE 6.5 at my disposal. I am looking to upgrade to something better (I’ve had Speed Edit recommended to me but I’d need a new machine too!). So for a moment let’s just stay with what I have. Both iMovie and iDVD have a DV Widescreen aspect ratio that is 16:9. If I struggle through in iMovie should I use HDTV 1280 x 720 even though my footage is no better then Mini DV? If I buy Final Cut Express or some other program will I have other screen aspect ratio options?
Thanks!
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6 Replies
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If you’re going to play the vid on a tv (presumably via a dvd) you’ll need to use either 4:3 or 16:9 aspect ratio with non-square pixels. Those are the only formats dvd supports. Use the presets in AE. The image in the comp window will look distorted, but use the toggle aspect ratio switch in the comp panel (it’s there in AE 7 & CS3 but I’m not sure about 6.5). Whether you toggle it on or off won’t affect the final output, which will be fine in either case, it’s just to give you an impression of the final output inside of AE. Widescreen square pixel will always look right inside of AE, but you won’t be able to add it to a dvd project once you’ve rendered it, as far as I understand the issue.
I’ve not used final cut, so not sure about the aspect rations, but I would be surprised if they didn’t include all industry standards like Premiere / AE.
Simon Bonner
youtube.com/simonsaysFX -
Yes, I’ll be playing the video via DVD. If I select a screen aspect ration of HDTV 1280 x 720, I’ll get my 16:9, correct? Now, the preset for that is square pixels, so my Photoshop imports are good. But what about video, Mini DV and stock footage converted from Beta SP? Should I render those separately with a different pixel aspect ratio, or should I use the Interpret Footage dialog box? Not sure about these issues!
Thanks again.
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If you’re going down the DVD route, you’ll need to use 16:9 non square pixels. DVD doesn’t support footage at 1280×720, even though it’s 16:9. It will only take 720×480 (720×576, PAL). This is important, because if you take the time to render out your footage at 1280×720, you’re going to find that Encore (or whatever software you’re using) won’t take it. I’m using Encore 2.0, which has DVD support but not HD, so perhaps you will be able to import your footage into Encore CS3 if you have it, but you won’t be able to bring it into a conventional DVD project.
As for your photoshop images, you can drop those into a non square comp and they’ll look just fine as AE will “spead the pixels out” so to speak, so they’ll fit. There will be a loss of resolution down to DVD quality, but as the rest of your footage will be at the quality anyway it won’t be a problem. Or you can set your PS images to have 1.42 pixel aspect ratio so they’re ready to bring into a 16:9 non-square pixel comp without AE needing to make any automatic interpretation at all.
As for your converted footage, I’m not familiar with the existing aspect ratios so I’m not sure. But you can’t have different aspect ratios in the same video. You can have 4:3 and 16:9 on the same DVD, but not in the same video. I also wouldn’t play with the interpret footage dialogue box: if footage with non-square pixels is reinterpreted as square pixels, for example, AE will just get confused.
Simon Bonner
youtube.com/simonsaysFX -
I am using what I have available to me right now- After Effects 6.5, iMovie and iDVD. Before I read your latest post I rendered out a file using 1280 x 720 and it seemed to import fine into both iMovie and iDVD, filling up the screen nicely. The earlier 720 x 480 file left black bars on each side when imported. Maybe these programs support 1280 x 720?
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I also haven’t used the programme, but perhaps it is “smarter” than Encore in that it can tell what aspect ratio the imported video should be, even though it needs to be scaled down, as Dave said. 1280 x 780 can only be interpreted as widescreen, so the programme must be downgrading to 720 x 480 16:9. Importing 720 x 480 gives the programme a choice between interpreting as standard 4:3 or widescreen 16:9, and it may be getting it wrong. Encore always interprets correctly in my experience, but iDVD could be different. Is there a way of checking how iDVD is interpreting your footage? If so, check it’s giving you the correct pixel aspect ratio for standard def 16:9.
Simon Bonner
youtube.com/simonsaysFX -
In iDVD, go to Project > Project Info where the project can be set to Widescreen 16:9 or Standard 4:3.
However, I’ve found that if you create a 16:9 project and drop in a 4:3 QuickTime MOV (I forget the exact codec settings at the moment), iDVD correctly encodes it as 4:3 aspect with black sides, ie. not undesirably stretch it out to 16:9.
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