I am using a Mac Pro dual quad with 14 Gigs of ram. In AfterEffects CS3 I am trying to chromakey SD component video recorded on Beta, captured on an Avid, and exported to me, as Meridian 1_1 compression Quicktimes. I am using Keylight.
I can get a good looking key during preview, and when I switch an unaffected top layer on and off I don't see any change in how the video looks (except for spill suppression.) Yet when I look at the final render output, the chroma keyed footage appears soft, and there is color saturation loss, and a lot of noise visible. I have tried (Quicktime) Avid Meridian 3_1 and 1-1 compression output, and finally rendered the comp out as a pict sequence, and then rendered that pict sequence back to an Avid quicktime: in each final render the keyed footage looks soft and noisy while the background plate (from a pre-rendered uncompressed movie I made in AE) looks clean and sharp.
Another problem (hence the pict sequence renders) is that After Effects keeps crashing during the render when I am using Keylight. The source quicktimes are quite long: the shortest is about 1:30, and the longest is almost 15:00 (minutes.) At least with a pict sequence, I can pick up the render from the last frame. Is there an optimum file size for the source quicktimes? Am I trying to render files that are simply too big for AE and my computer to manage?
I have looked through the forums but haven't found any problem exactly matching mine, and was hoping to see if anyone else has had such problems, and what their solution might have been.
For your crashing problems, you might want to double-check your footage in AE. Make darned sure none of it uses interframe compression (MPEG1, MPEG2, mp4, m2t, H.261 or H.264). Despite the Adobe propaganda to the contrary, they just plain ol' don't work, so change 'em to a different codec.
If you're on an ancient Windows box, you may be using the dreaded Fat 32 disk formatting, which limits file sizes to 2GB. I'm a Mac guy, so consider the source.
With your current woes, it's a good idea to render to image sequences. You MIGHT be able to help yourself out by purging the image cache every so often. Go Shift-After Effects>Preferences, find the Secret prefs and tell it to purge every X number of frames. It it happens at two minutes (about 3596 frames NTSC), try setting it to purge every 3000 frames. It slows down the render, but at least you stand a better chance of getting through it.
Once you have a rendered image sequence, you can reimport the footage into AE and use the Render Queue to Make Movie. The resulting render will go REALLY fast: all the heavy lifting will already have been done. And if your final file from AE is the keyed subject over an alpha channel, you might consider importing the background into AE and doing everything at once.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: keylight and crashing by Kenneth Kirkpatrick on Jul 14, 2008 at 10:40:31 pm
Dave:
Thanks for your reply. I tried a couple more test based on your comments. I rendered out a segment of the original clip to a PSD sequence. Then by mistake I rendered out a clip of the chromakey (using no compression) without using lower-field-first. It looks fine. When I rendered it again, exactly as before, except using lower-field-first, it looks blurry. I've tried several ways, now: PSD to uncompressed, uncompressed to uncompressed, etc., and it's only when I used a lower-field-first output that I get the softening issue.
Have others encountered this in AE using field-rendering? I have to use field-rendering, don't I, when using interlaced footage, to avoid field-order issues?
Re: keylight and crashing by Dave LaRonde on Jul 14, 2008 at 10:57:26 pm
[Kenneth Kirkpatrick]"I rendered out a clip of the chromakey (using no compression) without using lower-field-first. It looks fine. When I rendered it again, exactly as before, except using lower-field-first, it looks blurry."
Okay, before you started working on the key, did you remember to INTERPRET your footage as lower-field first? You need to do that, too.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: keylight and crashing by Kenneth Kirkpatrick on Jul 16, 2008 at 12:46:33 am
Yes, that's the first thing I do. That's what's stumping me now. If I don't interpret it I get all kinds of problems. We use Beta to record our chromakeys (it's cleaner than DV) but I don't have the option with Beta to shoot progressive.
I have to interpret fields, or I get field blending problems. Assigning field order doesn't seem to be the problem. Rendering with field order, no matter what output choice I make, seems to be my problem.
Re: keylight and crashing by Chris Wright on Jul 16, 2008 at 7:50:26 am
*I rendered out a clip of the chromakey (using no compression) without using lower-field-first. It looks fine."
ok, here's what's up, when you render a betacam out with fields off or a psd, you're rendering out a poor man's deinterlace from AE's built in deinterlacer. That's why when you reimport it back into AE and try interpreting it with fields on, you get blur. Of coarse you do, you're trying to deinterlace deinterlaced footage!
The quicktime codec might be giving you trouble. Try a different codec and render that out fields on. Chances are, you will then successfully import it back in and it won't be blurry. Whenever I have a problem, I render out 10 seconds of a 4:4:4: RGB uncompressed avi. That fixes 99% of problems.
Re: keylight and crashing by Kenneth Kirkpatrick on Jul 16, 2008 at 6:04:42 pm
Chris:
Thanks for your post.
I've tried all your suggestions. I was able to get it to output a clean, uncompressed, unkeyed clip as per your suggestion.
But when I take that clip and run it through Keylight with lower field output, whether to a Quicktime or an image sequence, I get the softening effect. I can get a better looking render when I use no field. It is crisp, but there is still detail loss because I'm missing a field. That is acceptable for this project, which is for the Internet.
But I still want to know why this process, which has worked so well before, no longer works. Also, I'm still having the other problem of AE constantly crashing while I'm rendering: I can't leave a render queue going overnight, and I have to constantly babysit the render.
Re: keylight and crashing by Dave LaRonde on Jul 16, 2008 at 6:10:33 pm
[Kenneth Kirkpatrick]"...I still want to know why this process, which has worked so well before, no longer works. Also, I'm still having the other problem of AE constantly crashing while I'm rendering..."
We can't answer that, only you can -- what changed, either about your shooting or your computer, when you first noticed this happening?
The answers will be your best clues.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: keylight and crashing by Chris Wright on Jul 16, 2008 at 8:14:17 pm
You might have image sequence settings wrong because flash only supports pre-multiplied and needs alpha channel- rgb+alpha. and there's quality settings for image outputs like PNG(format options) which has a box for interlaced output for web viewing support.
By storing gamma information in an image, PNG's can be transfered to mac back to pc whithout color problems, which makes me wonder why more people don't use this fantastic image sequencer.
If those are correct, then the only other thing is keylight, update it or even try a demo of another keyer.
Re: keylight and crashing by Kenneth Kirkpatrick on Jul 16, 2008 at 9:15:12 pm
Dave and Chris:
Thanks for both your responses.
Dave: I've kind of run out of ideas on what it could be, hence the posts. Shooting hasn't changed: we shoot component video on Beta to avoid DV compression. We capture in this case in Avid using Meridian uncompressed 1 to 1 codec.
At first I thought it was the latest Avid codec, but then I was having the same problem when I rendered the sequence to the uncompressed None codec in the output dropdowns.
Chris: Flash isn't at all in the picture. I'm not rendering the chromakeys out as matte channel files, but as comps over the background with audio.
The weirdest thing is, everything looks great in the comp window. Then, the instant I hit render, I see the image go soft.
Again, thanks for the input. I'm going to have to give it a rest and get back to my scheduled tasks.
Re: keylight and crashing by Johannes Toenne on Jul 29, 2008 at 10:03:11 am
has anyone found a solution for that soft, blurry image problem, 'cause i have it too.
footage looks great in comp window, but as soon as i render it with animation, it is blurred. if i remove keylight, it sharp. i tried different codecs, i searched everywhere but couldn't find a solution. i already installed the keylight update, but no help.
