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# Good Pixel speeds for Scrolling credits

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 Good Pixel speeds for Scrolling credits on May 14, 2010 at 7:46:52 pm

I finally figured out how to make scrolling credits in 59.94 HD look good when downconverted to NTSC. I new 120 pixels/second was the way to go for NTSC but I never even though to increase that rate for the HD. For center cut and anamorphic downconversions it's 270 pixels/second and for letterbox downconversions it's 360 pixels/second.

I'm sure this has been posted somewhere. I could never find it though. I just realized that the HD image is much larger than 480 so 120 pixels in HD does not equal 120 pixels in SD when downconverted.

I hope this helps somebody.

 Re: Good Pixel speeds for Scrolling creditson May 14, 2010 at 8:05:49 pm

[Eugene Lehnert] "I new 120 pixels/second was the way to go for NTSC..."

Actually, no. I bet you were thinking something like, "at 120 pixels/sec, that's 4 pixels/frame". You got that figure by dividing 120 by 30.

But NTSC is 29.97 frames/sec, not 30! Dividing by fractions! Eeeeewwwww! Ever get a good, critical look at nice, crisp 30fps motion graphics footage played back in a 29.97 NLE edit timeline? It ain't too pretty.

But a much smarter guy than me figured out a solution. From Kevin Camp, here's an expression for flicker-free credit rolls. Just copy the stuff in bold and paste:

rate = 2; //value in px/sec.
if (marker.numKeys > 0){
if (time > marker.key(1).time){
value - [0,rate*timeToFrames(time-marker.key(1).time)];
}else{
value;
}
}else{
value - [0,rate*timeToFrames(time-inPoint)];
}\

just position the roll where you want it to start and it will march up the screen at the rate that you set. even rate values should be used if you are rendering to an interlaced format, and if you set the rate too high the roll will appear kind of strobe-like.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA

 Re: Good Pixel speeds for Scrolling creditson May 14, 2010 at 8:37:24 pm

I don't know. I found the 120 pixels/second rate inside of one of Trish and Chris Meyer's After Effects books a long time ago. That speed combined with rendering the file with fields looks the best of any scroll I've seen on an interlaced monitor. Granted it doesn't look good on the computer screen and it's kind of a fast speed. I'm doing some tests with that expression you kindly provided but the results not not seem as clear but the scroll does not seem to have the same speed as 120 pixels/second. I believe Trish Meyer also mentioned that you would have to go to 240 pixels/second for another speed but that would be incredibly fast.

 Re: Good Pixel speeds for Scrolling creditson May 14, 2010 at 9:50:13 pm

There's information about creating rolling credits here:
"Best practices for creating text and vector graphics for video"

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 Re: Good Pixel speeds for Scrolling creditson Jun 30, 2010 at 2:41:22 am

"But a much smarter guy than me figured out a solution. From Kevin Camp, here's an expression for flicker-free credit rolls. Just copy the stuff in bold and paste:"

Hi Dave, I've been reading stuff for 2 days now about the "mercury jones" preset (which I can't find anywhere) and expressions.

I'm still very new to AE, can you please explain to me where I'm supposed to paste the expression you posted?

I never thought it would be this difficult to make rolling titles. It takes no time at all in Premiere Pro, but obviously I'm spending a lot of time trying to learn so I can make titles that don't flicker.

Am I supposed to use a camera with a null object to move the titles? I also tried using "autoscroll" but I can't seem to start the titles off-screen, and it won't show me what's written off screen (it just keeps repeating what is actually showing on-screen). I'm assuming it has something to do with "motion tile", but I have no clue.

Marc

 Re: Good Pixel speeds for Scrolling creditson Jun 30, 2010 at 11:11:43 pm

Enable the expression for the position property of the layer that will do the vertical roll: Option-click on the stopwatch for Macs. Figure it out for Windows. Copy the expression text you see in the post, and paste over the existing expression text in the layer.

This expression supersedes the old Mercury Jones preset. Follow Kevin's instructions in the post and you'll be okay.

Some applications can do no-brainer, great-looking credit rolls, but it's tough in AE. Heck, some Hollywood movies can't get it right. Go check out the credits on last summer's Star Trek movie and you'll see what I mean.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA

 Re: Good Pixel speeds for Scrolling creditson Jul 18, 2010 at 2:59:30 am

I pasted the expression and I get this warning:

After Effects warning: class 'layer' has no property or method named ''

expression disabled.

I'm not sure if I'm supposed to enter a "rate" or if the expression is just supposed to work by itself?

You also said, "Follow Kevin's instructions in the post" I don't know what post you're referring to?

And lastly, I couldn't remember anything wrong with Star Trek's credits so I popped in the Bluray to check, and I can't see what you mean?

Marc

 Re: Good Pixel speeds for Scrolling creditson Jul 18, 2010 at 4:50:18 am

I have a silly question:

My film was 2 perf 35mm (2.35:1) and I did a 2K scan, to finish at 1920x1080 (with an image are of 1920x817 for the 2.35:1 frame matted in) for HDCAM-SR delivery. I just finished my credits and I have used the wonderful expression here to get nice and smooth credits. My only question is this: Should my credits also be 2.35? Should my AE comp be 1920x1080 and scroll the 16:9 frame vertically or should the comp be 1920x817 and maintain the 2.35 frame?

Abel Cine Tech - Rental Coordinator
We now have Red and SI-2K in our Rental Fleet!
212.462.0163 • mnichols [at] abelcine [dot] com

 Re: Good Pixel speeds for Scrolling creditson Jul 19, 2010 at 3:34:59 pm

[Michael Nichols] "Should my credits also be 2.35? "

I'd say it's time to talk to the client about delivery specs. You shouldn't have to second-guess the client, because sometimes you get it wrong, and that's never good.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA

 Re: Good Pixel speeds for Scrolling creditson Jul 19, 2010 at 5:50:16 pm

Hey Dave,

Thanks for the reply. I guess, since I am the client, I answered my own question. I built the comp in a 2.35 frame. Just wanted to make sure there was a standard set already when finishing 2.35 to tape.

Abel Cine Tech - Rental Coordinator
We now have Red and SI-2K in our Rental Fleet!
212.462.0163 • mnichols [at] abelcine [dot] com

 Re: Good Pixel speeds for Scrolling creditson Jul 19, 2010 at 6:04:09 pm

[Michael Nichols] "I am the client... Just wanted to make sure there was a standard set already when finishing 2.35 to tape."

Excellent! You should then be able to get a lightning-fast answer on whether the product you need to deliver should be 1920x1080 anamorphic to be used at 2.35:1, or letterboxed to accommodate 2.35:1.... and I think you already have the answer

The only potential problem: to sit smack-dab in the middle of a 1920x1080 frame, your animation's center point will have a half-pixel vertical value: it's an odd number, not even. Or you have to make a choice: one pixel too high, or one pixel too low.

The client may have anticipated this, so it may not pose a problem.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA

 Re: Good Pixel speeds for Scrolling creditson Jul 19, 2010 at 6:16:36 pm

[Dave LaRonde] "Excellent! You should then be able to get a lightning-fast answer on whether the product you need to deliver should be 1920x1080 anamorphic to be used at 2.35:1, or letterboxed to accommodate 2.35:1.... and I think you already have the answer

The only potential problem: to sit smack-dab in the middle of a 1920x1080 frame, your animation's center point will have a half-pixel vertical value: it's an odd number, not even. Or you have to make a choice: one pixel too high, or one pixel too low."

Well, I am going letterboxed (matted?) because I am a little unclear on any other way. My files are native 2.39 (1868x780 DPX scans) that I have to scale up and matte into a 1920x1080 frame. Is that not the correct method for this?

Regarding your 2nd point, I am confused as to why that would pose a problem (half pixel vertical value for center point). Would that disrupt the math?

Abel Cine Tech - Rental Coordinator
We now have Red and SI-2K in our Rental Fleet!
212.462.0163 • mnichols [at] abelcine [dot] com

 Re: Good Pixel speeds for Scrolling creditson Jul 19, 2010 at 6:42:31 pm

[Michael Nichols] "Regarding your 2nd point, I am confused as to why that would pose a problem (half pixel vertical value for center point). Would that disrupt the math?"

There's a possibility -- a slim one -- it could soften up your graphics; certainly worth a test with a short-duration example.

Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA

 Re: Good Pixel speeds for Scrolling creditson Jul 24, 2014 at 6:29:52 pm

Thank you -- can you please tell me where to "paste" that expression. I am a novice, working in FCP 7, I've completed a 30 minute doc film, looks great (thanks to many tips I've taken from you directly, and other Creative Cow contributors) - except for the darn credits, they are jittery. Would like to start over and build in Motion 4.

How do I get that value/rate into my settings in motion? Any guidance or advice would be greatly appreciated.

Margaret