My RAM preview keeps getting shorter and shorter. When i first load my scene I can do like 300+ frames of ram preview, but after not to long it will stop at like 12 frames. I can do the purge, and then I get back up to 50 or so which quickly drops back down.
Whats going on?! Does RAM preview care about the complexity of layers generating your scene? Seems like pixels are pixels are pixels, regarless of how they got generated.
Like the name says, RAM preview is dependent on how much RAM is available to AE. The higher your resolution, and the bigger your images, and the more stuff you do, and the more stuff gets cached, all has an impact on how much RAM is left for storing Preview frames. If you have 20 x 4K stills in your comp, AE will need plenty of RAM to load them before it can composite them and render a Preview.