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bingjoe
11-25-2011, 10:48 AM
Hi,

I have been rendering an animation at 1280 x 720 ( HDTV ) square pixels, however, my primary target platform is PAL DVD. At the moment, I import into Premiere and output to DVD and it's fine.

Am I gaining / losing anything here, or should I be rendering my source as D1 (PAL Widescreen ) which is 720 x 526 with a pixel aspect ration of 1.4222 ?

I guess the D1 (PAL WS) frames would render quicker than the HDTV frames ?

Thanks,

Joe

nickdigital
11-25-2011, 11:02 AM
Yes, your LW renders would take less time because you're rendering less pixels.

I assume you're cropping your output to fit the PAL size?

Dexter2999
11-25-2011, 12:11 PM
FWIW, I wouldn't render in the 1280x720 format even for HDTV. That is sort of a left over standard for 720P. People now using HD are looking for 1080P (the other HDTV camera which was previously used for the 1080i standard).

But as you are using PAL none of that really matters.

bingjoe
11-25-2011, 12:16 PM
Hi,

No - no need to crop. Comes out fine (all 16:9)

One more confusing thing, Adobe recommend square pixel input for D1 PAL widescreen should 1050 x 576 !!!!!!

(Brain hurting now)

Joe

bingjoe
11-25-2011, 03:42 PM
Still a bit confused as to why Nick thought I needed to crop !?!

Dexter2999
11-25-2011, 04:21 PM
Because you indicated that your render was set to HDTV rather than PAL. PAL is 720x576.

Now you are indicating that you actually need a hybrid resolution which is the PAL equivelant of Enhanced Definition by having an extended width (720 extended to 1050) but maintaining the PAL number of lines of resolution (576).

wrench
11-26-2011, 02:13 PM
But also the pixel aspect can't be 1:1? PAL widescreen is set as 720x576 as normal, but with an aspect of 1.422, meaning that the pixels are spread horizontally to nearly one and a half times their normal width.

B
PS. I know The Dommo has done a lot of DVD projects and will be able to help.

nikfaulkner
12-28-2011, 12:52 PM
for pal 16:9 i render 1024x576(square pixel) then convert the movies aspect ratio to be anamorphic 720x576 in after effects.

this way i can create 4:3 crops if i needed.

biliousfrog
12-28-2011, 01:22 PM
for pal 16:9 i render 1024x576(square pixel) then convert the movies aspect ratio to be anamorphic 720x576 in after effects.

this way i can create 4:3 crops if i needed.

Yep, PAL widescreen with square pixels is 1024x576 I have no idea where 1050 has come from. When importing in to premiere select square pixels and it will change the aspect on export if required. Personally I never render anything with non-square pixels.

Sensei
12-28-2011, 05:46 PM
I would render multiply of 1920x1080 without any AA or AS.. Then scale down in Photoshop etc to whatever is needed at the moment.

Rendering in 3840x2160 and then rescaling to 1920x1080 is like using AA passes 4 (maybe more because there is more data around pixel). Rescaling to 1280x720 would be like at least 9 AA passes.

medicalart
12-28-2011, 06:06 PM
Is the Lightwave default to render square pixels? I've never paid attention to this, but just got Premiere and am trying to figure out what settings to use. If I want 4:3 frame aspect ratio (720x540) Premiere says to render at 720x534 (NTSC) or if 16:9 frame aspect ratio, do 864x480. Can anyone recommend LW camera settings in pixel dimensions, (and are they square) or at least point me in the right direction. Thanks.

biliousfrog
01-05-2012, 11:35 AM
In Lightwave - camera options - "aspect" controls the pixel aspect ratio, 1.0 is square. The camera presets also adjust the aspect ratio, HDTV uses square pixels for example.

In premiere you can select a custom frame size and aspect ratio. It varies according to the version, CS3 had a preset at the top but CS5+ lets you select "settings" and change it there...this is all from the preset window that opens when you select a new project.

Personally, I prefer working in square pixels and exporting to non-square if required from the media encoder.

This page gives you the theory and math but, if you scroll down towards the bottom, there's a reference table with the pixel sizes for NTSC and PAL using square pixels.

xxiii
01-05-2012, 12:33 PM
This page gives you the theory and math...

Was there supposed to be a link/reference here?

After Effects/Media Encoder keeps wanting to default to non-square pixels, but on playback it still looks correct, so I assume the playback device/software converts them back. This seems like a lot of unnecessary transformation. I've since made my own Media Encoder preset to specify square pixels, but this nags at me (mainly because I'm not entirely sure blu-ray et al. actually understand frame aspect as well as I'd like them to... I must research this I suppose).

Is there any modern reason to want to use non-square pixels? I assume this is a holdover from the analog days and trying to maximize detail from inflexible devices, such as changing the pixel aspect ratio to cram an anamorphic film onto a laserdisc without wasting any bandwidth storing black bands, and then using a corresponding lens on a projector (or a "smart" laserdisc player than can "fix" the aspect ratio and generate black bands).

Or are we in a "lightbulb" situation where we will be stuck with measuring brightness in watts for the forseable future even though its incorrect, because of tradition and familiarity, even though recent lighting technology is increasingly showing how ridiculous it is to specify brightness in watts?

And, its time for interlacing to seriously consider retirement as well. Maybe I'm misunderstanding something, but these seem like holdovers. So, my encoder has to convert my progressive square-pixel frames to interlaced non-square pixels, so the display device can de-interlace it, and convert it back to square pixels for display purposes...

This reminds me of when the phone company finally wised up and realised they should stop charging extra for touch-tone dialing. Having had a push-button phone that would convert it to pulse dialing, where an extra device at the phone company end would convert the pulses back to touch-tones, but they would charge you extra to NOT put this intermediate device on your phone line, hence the market for push-button phones that could generate pulse dialing. (And, I suppose the occasional rural area that hadn't yet "modernized" their phone systems by the mid 80's, in spite of touch-tone being around since 1960).

biliousfrog
01-05-2012, 01:18 PM
erm...woops...

http://www.mir.com/DMG/aspect.html

The most common HD formats use square pixels and progressive scanning. AFAIK DVD's are encoded as interlaced but are converted to progressive by the player which I've never understood, perhaps someone can clarify that. BluRay is progressive and square pixels (1080p), Most digital footage is square pixels and progressive. I suspect (but don't know for sure) that all modern, digital, TV's have square pixels and display progressively...

wrench
01-05-2012, 01:23 PM
Wow, he's really up with the times... VCD and SVCD? No DVD or BluRay?

B

zapper1998
01-05-2012, 01:29 PM
FWIW, I wouldn't render in the 1280x720 format even for HDTV. That is sort of a left over standard for 720P. People now using HD are looking for 1080P (the other HDTV camera which was previously used for the 1080i standard).

But as you are using PAL none of that really matters.

so for todays 1080i what camera settings are used???

medicalart
01-05-2012, 02:53 PM
Here's a good explanation of pixel and frame aspect ratio:

http://help.adobe.com/en_US/PremierePro/4.0/WS03BF7479-8C7B-4522-8C75-210AD102524Ea.html

I imagine that the distortion is minimal, unless I bring footage into LW and then export it again.