Problem with 60fps preview and external monitor

[axelv]

Hi all, I have a problem with the preview and composition at 60fps. When I try a preview (spacebar) the animation start at 60fps but after one second it starts to drop down to 35fps. If I resize the After Effects window to a quarter screen, it's okay. I have a Dell 32 ”connected to the Macbook Pro 2017 with a 60hz displayport cable.

Can you help me?

[Mylenium]

You need to read the online help on how previews in AE actually work. There is no guarantee that full framerates can be guaranteed under any conditions, even more so with the weak and dated graphics hardware that Macs have. That's what RAM previews are for. The online help is your friend.

Mylenium

[axelv]

Thanks for reply, this is RAM preview.

[Rick Gerard]

Set your Preview Panel to skip one frame, set your Comp Panel resolution to Auto, do most of your previews at 50% Magnification ratio, enable Mercury Transmit and select your external monitor as the preview monitor, you should be fine unless you are completely out of ram. The preview function in After Effects is useful for previewing motion and timing. Your eye can't tell the difference between 29.97 and 59.94 (60) so skipping frames will give you a longer preview. 

AE is no a video editing app and any attempt to use AE for editing video is a lot like driving nails with a screwdriver. Use the right tool for the job. I would wager that close to 90% of the comps that professionals create that involve compositing or visual effects are one-shot that is under seven seconds. Last year, that was true for me, but this year, because the average cut in a movie has gone down, most of my comps are 5 or 6 seconds. I'm working on one today that is only 91 frames. It has a total of 85 layers and a dozen nested comps (pre-comps). I haven't run a single full-resolution real-time preview yet, but I did run about 40 1/4 rez, no FX, no motion blur previews to get the timing of the effect right. I call those pencil tests. I stopped on four or five critical or hero frames and checked them at 200% and full resolution to make sure the edges were perfect (I call that Ink and Paint), and now I'm ready to render. 

[axelv]

Thanks also to you for the reply. The only setting that helps me and that works is "skip one frame" in the preview panel. My composition is 97 frames long, it is composed of 28 shape layers and only animates the scale and position. The composition is also 512x512px. I find it absurd that a composition like this cannot be seen in real time at 60fps. However, even when setting "skip one frame" the result is excellent. Can't see the preview not in realtime at 60fps with AE window in full screen, it's horrible. You don't realize the result and it is difficult to work.