Scaling bitmaps - lost quality.

[Mike Roberts]

Hey guys,

Just trying to sort out my workflow. Right now I'm having a problem where i'm using very large bitmaps and scaling them down so i have lots of resolution if i need to punch in. But if i scale it down too much - the image loses quality pretty badly on render. Is there a way around this?

Also - when i scale, the bitmaps revert to their original size if i change the original artwork. Is there a way around that?

[slowtiger]

OK, some basic workflow tips.

Don't make your bitmaps too large, only as large as needed (if you know beforehand). I've noticed I can even enlarge my (self painted) bitmaps by 1.2 without anybody noticing most times. And for multiplane setups the blur on heavily enlarged bitmaps is exactly what I need, and AS does this really nicely.

I've never noticed loss of quality by downscaling, but this may depend on the image's content. If there's no zoom involved in the scene I also work with smaller versions of the same bitmap to reduce rendering time.

Changing original artwork: I don't use Photoshop files in AS, only PNG. AS' behaviour can be a bit tricky. The safest way is to open the image layer panel and assign the new bitmap to it. If I overwrite the PNG file with the same file name, AS may show the change immediately. However, some programs don't let me overwrite the PNG as long as AS is open and uses that file. In this case I have to close AS, create the new file (with same name in same place), open AS and it shows the new version.

This only works as long as your replacement file is of the same pixel dimensions as the original. If you have different dimensions in the bitmap it will show up distorted in AS.

Mind your project settings. If you want all your bitmaps imported in the correct size, don't change project dimensions between importing.

[Mike Roberts]

Good to know, and thanks for the thoughtful reply.

I'm trying to make a practical workflow - which i think will just mean making things as large as I might need them and scaling them down in after effects. The only drawback is render time, but it'll pay off in not having to create as many puppets!

Thanks again...