Preserving 720x480 square aspect ratio in iDVD

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Level 1

67 points

Preserving 720x480 square aspect ratio in iDVD

Hi, I posted this question in the iDVD group and was told there might be a FCP answer.

I'm importing a 720x480 (3:2) aspect ratio movie with square pixels into iDVD. iDVD scrunches it up and makes everyone look too tall and thin, though the movie looks fine in QT. Are there any special settings in FCP when exporting that can assure the proper aspect ratio in iDVD? (I was told iDVD only supports 4:3 and 16:9, which may make this a moot question.)

thanks,
Scott

Macbook Pro, Mac OS X (10.4.11), FCP 6

Posted on Apr 27, 2008 12:39 PM

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Answer 1

Apr 27, 2008 1:45 PM in response to Scott Stark

Your 720x480 has square pixels? That's a non standard format. iDVD expects 4:3 video assets to be 720x480 with NTSC-DV pixel aspect ratio.

In FCP, center your footage in a 4:3 NTSC composition. (It will have black bars at the top and bottom) Export that and bring the file into iDVD.

Where did you get this footage by the way? If you're creating square-pixel assets (in photoshop or after effects for example) for a SD NTSC project, you should create them at 720x534 (for 4:3) or 864x480 (for 16:9).

When importing anamorphic 16:9 assets into FCP, make sure the 16:9 flag is checked in the browser (sometimes you have to do this manually). And make sure the asset is recognised as 16:9 in DVDSP also. iDVD used to have problems with anamorphic assets, not sure about latest versions. If in doubt, you can use something called anamorphicizer (google it) to set the 16:9 flag in the quicktime file.

Best of luck and hope this helps.

Message was edited by: Denis Murphy

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Answer 2

Scott Stark Author

Level 1

67 points

Apr 27, 2008 5:31 PM in response to Denis Murphy

Denis Murphy wrote:
Where did you get this footage by the way? If you're creating square-pixel assets (in photoshop or after effects for example) for a SD NTSC project, you should create them at 720x534 (for 4:3) or 864x480 (for 16:9).

I created it from a FCP sequence with 720x480, square pixels, 24 frames per second. My goal is to output the sequence as a series of Targa still images which can be output to 35mm film. That's why I want the 3:2 ratio rather than 4:3, and I've discovered if I don't use square pixels the Targa still images are distorted.

I was able to get what I wanted in iDVD by 1) outputting my original 720x480 square sequence to quicktime; 2) reimporting it into FCP and inserting it in a 640x480 NTSC-CCIR 601 pixel aspect ratio (kind of like you suggested), 3) exporting that again as quicktime, and 4) importing that file into iDVD. The funny thing is, in the FCP 4:3 sequence the image looks distorted (scrunched from the sides so everyone looks too tall and thin), but when I import it into iDVD it stretches back out to normal again. (When I changed the pixels to square in the Browser before dropping it in the sequence, it looked fine in the sequence but stretched sideways in iDVD. Go figure.)

What a lot of back and forth! But I got what I want, and I thank you for your suggestion.

Now I'd like to figure out how to deal with what I suspect is frame slippage on the DVD from my original 24fps, but I think I can deal with that, as DVD is not the final output.

thanks!
Scott

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Answer 3

Apr 28, 2008 5:32 AM in response to Scott Stark

Hmm, so the DVD is just for viewing purposes then?

From what you posted here, the distortion should still have been evident on the DVD, although it's unclear what you did on your final export from FCP.

If you want to burn viewing copies of your 3:2 material, remember that iDVD can only deal with native 4:3, so simply drop your 3:2 sequence into a standard 4:3 sequence (it will default to a slightly letterboxed frame) and output that to a 720x480 CCIR-601 quicktime. Kind of like what you did, but saves you a step or two (no real need for the interim exports).

Re the frame "slippage:, I don't think iDVD can burn 24fps DVDs. Some sort of pulldown was probably added. Can't say for sure because I only ever work with 25fps PAL.

Best of luck anyway.

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Answer 4

Scott Stark Author

Level 1

67 points

Apr 28, 2008 6:38 AM in response to Denis Murphy

Denis Murphy wrote:
Hmm, so the DVD is just for viewing purposes then?

Yes, for preview purposes. Thanks again for the suggestions.

thanks,
Scott

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Answer 5

Studio X

Level 7

27,229 points

Apr 28, 2008 6:58 AM in response to Scott Stark

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Answer 6

Apr 28, 2008 3:54 PM in response to Studio X

BTW Scott, 720x480 square seems way too low a resolution for creating elements for 35mm projects - unless the elements contain largely NTSC video, which begs the question, why not create at a higher res?

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Answer 7

Scott Stark Author

Level 1

67 points

Apr 28, 2008 4:44 PM in response to Denis Murphy

Hmm, well I'm using all still images, mostly 5 mexapixel stuff and some scanned images at 4000 dpi. I did a one minute test and thought the images looked great, but now you've got me wondering if it could be improved.

Scott

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Answer 8

Apr 28, 2008 4:48 PM in response to Scott Stark

Wow yes, you can do a lot better than that. Use the 2k sequence preset at least, if your goal is to output to 35mm film.

Your images would have looked great in the 720x480 square pixel FCP canvas, but by the time you print this to film it'll look pretty cruddy.

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Answer 9

Scott Stark Author

Level 1

67 points

Apr 28, 2008 6:42 PM in response to Denis Murphy

Wow, yes I did a test and you're right, the difference in resolution is astounding. Thanks for the tip, glad to hear that before I got too deep into this project (although I'm pretty deep already)!

Of course each targa image is now 20MB instead of just 1.3, so now I have to think about disk space... 🙂

thanks,
Scott

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