PAR question

[David Johnson]

This probabaly won’t help you solve your problem, but I use the exact process you described with Invigorator projects and have never gotten jagged edges. Maybe check your “object faceting” in Invig. Also, make sure your’re not getting a draft version due to AE’s render settings over-riding your comp’s resolution setting or something like that…I know that’s obvious but it happens.

[Greg Cotten]

Deinterlacing should do the trick (I believe you can interpret the footage that you placed in the 720×486 comp)… but why are you working in a 720×540 comp anyway? What does this have to do with PAR (Pixel Aspect Ratio)?

-Greg

[Brandon]

Because, I was always told to work in a 720×540 square pixel comp. Then when it’s time to render, make a 720×486 non square comp. Put my 720×540 comp and size to fit. I just have been doing what they told me to do.

[Steve Roberts]

There’s nothing wrong with working in a 720×540 comp then dropping into a 486 comp for rendering. However, if my sources are interlaced, I like to work in a 486 comp and occasionally use PAR correction until render.

1. Which layers are looking jagged and which do not?
2. Do you have any imported interlaced footage in the 540 comp?
3. Do the jagged layers look bad in the comp window or after a render?

Steve

[Brandon]

I am not working with any interlaced footage. I only have one layer so far, it’s the invigorator layer. The logo looks really good, but when I use the PAR correction it looks jagged. And Yes, it looks jagged after I render it out. Thanks

Brandon

[Steve Roberts]

You should never render with PAR correction on. It is only for previews, to make non-square pixel comps look right on a computer. Non-square pixel comps will look correct on a TV.

For more info, search the COW for “strangepixel”.

Steve

[Brandon]

I don’t render with the PAR correction on. I dont know where I got that I did. I’ve read that strangepixel before. Thanks.

Brandon

[Aharon Rabinowitz]

No matter what, Pixel ASpect Ratio Correction allways looks jagged – so ignore that. It’s only to give you a rough idea
of what it will look like.

I might have missed this, but make sure your render settings are set to “Best Setting” and not “current settings”

Also, a lot of people make this mistake – even the experts – the correct square pixel equivilent for 720×486 (0.9) is 648×486 not 720×540. If you work at 720×540, you have to shrink it down by 10% which may create bad pixles.

If you use the resolution I just gave you (648×486 – there is a preset for it in AE, just like 720×540 and 720×486), and then take that comp and nest it into a 720×486 comp, everything should adjust itself automatically to look correct when you render.

If it still doesn’t work, run a test: Render at the square pixel aspect ratio – if it looks good, then import the video into AE and drop it into a comp at 720×486. Render. If it looks bad at either step, you may have some a problem with your renderer, though I can honestly not say what that would be.

Also, there is a Zaxwerks forum, here at the cow. If none of this helps, maybe they’ve seen this problem before.

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com

[Brandon]

How come, even in the Total Training for AE 6.5, they say to always work in a 720×540 then drop it into a 720×486 comp and render? Are they all doing it wrong then? Should I always work in a 648×486 comp? Then drop it into a 720×486 comp? Thanks

[Aharon Rabinowitz]

“Are they all doing it wrong then?”

In my opinion, for what it’s worth, YES. Most people say to do it this way, but it’s been my experience that if you plan on going to 720×486, you build your art in the square pixel equivilent of your non-square pixel comp – which is 648×486. Do the math – 0.9 x 720 = 648. The 486 (height) is not being stretched, so it stays the same.

Try this: If you make something 720×540 in square pixels, and drop it into a 270×486 (0.9) comp – then you will see that the image is too big. It needs to be shrunk down to 90% of it’s full size to fit properly. But if you make something in square pixels at 648×486 and drop it into the 720×486 (0.9) comp, it will automatically adjust itself – thanks to some help from AE’s PAR correction tools.

If you read Dr. Strange Pixel, you will see he says the same thing – the square pixel equivilent of 720×486 is 648×486.

One thing to think about – A pixel is a given size. It doesn’t change unless your PAR is changing. When you shrink something down to 50%, you are hiding every other pixel so it can fit into half the space – right? You can;t make the pixel any smaller, so it has to hide the pixels instead and tighten up the ones it’s showing. In may cases, it’s not noticebale, but sooner or later, especially in high contrast images moving and scaling up and down , you will see a shimmer or pixelation as pixels hide and show themselves over and over again.

If you shrink something down, you may have a problem – often/usually not, but sometimes it can be a real pain…

—————————————-
Aharon Rabinowitz
aharon(AT)yahoo(DOT)com
http://www.allbetsareoff.com
—————————————-
Creative Cow Master Series DVD
particleIllusion Fusion Volume 1
available @ http://www.pIllusionFusion.com