If I RAM preview a comp in After Effects at 1080i get about 7fps playback, if I switch the AJA preview to 720p (same comp) I get about 14fps playback. It's only when I switch the AJA preview to SD 486 that I get realtime playback. IS this normal? If so why??? If not, any ideas why it's so slow for me?
Yes, full range is rendered. My GPU card has 768MB of RAM.
I don't think it's related to the GPU, since the playback goes from 7FPS to full 30FPS, by just switching the Xena output resolution from 1080i to 486i.
Tim, do you get full-speed playback in 1080i, is this a problem with my setup?
Yes, I'm rendering and previewing the correct way, (I have been using AE for 15 years now). The problem is with the Xena card. I've found if I render and RAM preview a comp I get very slow playback with the Xena, if I uncheck the "preview during playback" in the AJA preview panel, the same RAM preview plays back realtime, no problems, even with 1080p comps.
So I assume this is not normal behavior (I hope not anyway) so I need to find out why.
thanks for the help,
No it doesn't help, even doing like a quarter rez quality makes no difference, and normally that would make a huge difference (at least in my experience with Axio and Decklink systems). It's definitely not normal, I will contact tech support and see if they can help.
OK, this is what I've found. If in the AJA preview window, I switch the color-options from 8-bit YUV to 8-bit RGBA, I get realtime playback for all comp sizes. Unfortunately this only happens with 8-bit projects, 16 and 32-bit projects will not preivew realtime, no matter what settings are adjusted. I was able to confirm this with AJA tech support.
So I'm guessing this is an issue with Xena and color conversion from RGB to YUV, but I'm not totally sure since it doesn't seem to work in 16 & 32-bit. Also, I don't know if this is LHi specific, or if the other Xena cards have the same issue.