Frame/Sec and EXR

Support Compositing and Post Processing
1

Hola all,

I hope I’m not asking beaten to death questions (couldn’t find quite the same here on the forum, but haven’t looked exhaustedly).

  1. I would like to render at 50fps for a slowmotion effect, but since I can only choose a frame-range for animation (start/end) and not time-range, I will not get those extra frames (for example 200 frames when the range is set to 1-100). Basically I’m not sure how to archieve this effect. Is it something with the “Frame per second base” setting? It doesn’t seem to affect anything…?

  2. I’m also a bit puzzled about renderlayers and openEXR. I thought .exr could contain the different layers in file (the reflection layer is important for this project), but after loading the .exr sequence in the node editor, it only has image, alpha and Z, not reflection or other layers. Am I missing something?

2

  1. FPS base is the number of frames blender will render per second of action. If your animation was set to be from frame 1 to 100 at 25 fps, it would need to be set to frame 1 to 200 at 50 fps. You basically need to multiply the fps base by the number of seconds in your video.

  2. the regular OpenEXR option will render standard EXR files that you can use in image editing software like PHotoShop. To render EXR with multiple layer to be used in the Blender Node Editor, you would set the Render options to MuliLayer.

3

Thank you!

One last thing, just so I can get it through my thick skull:

I change the range from 1-100 to 1-200, change 25fps to 50fps, but I leave “fps-base” at the default 1?

4

Sorry about that. I forgot that there was both an FPS field and an FPS Base field (starting in 2.46). The Base field is used for fractional frames like 19.97 NTSC. For your 25 or 50 fps the base would be 1. If you care to know more, look at the NTSC support section on this page:
http://www.blender.org/development/release-logs/blender-246/sequencer-changes/

5

Ah, I see.

Thanks again, DichotomyMatt, and also for the link. :slight_smile:

6

Hi again,

Well, the slowdown did not work in this case since we were using cloth-sim, and apparently those calculations are locked at 30fps. We fixed it by reworking the re-timed shots (filmed with RED). Too bad, though, since physics-sims are cool in slowmo :slight_smile:

I forgot to ask yesterday, about the difference between OpenEXR and Multilayer in Blender. Is Multilayer only functional in Blender? Opening .exr files with multiple layers in an external compositing app is very desirable. Is it a problem with the “fragmentation” of the format (or is that solved now)?

7

Here is what Blender.org has to say about the Multilayer format:

MultiLayer Images
The new MultiLayer image is transparently integrated in the UI. It can be used for textures, for backdrops, compositing, painting or viewing. As format it uses OpenEXR, loss-less compressed float channels (no other compression or ‘half’ float support yet).

This image type uses the same extension (.exr) by default. Whether it is a regular RGBA file or a MultiLayer file is detected automatically (files have a custom “BlenderMultiChannel” attribute, as discussed with the OpenEXR team.) Unfortunately no other imaging programs support OpenEXR multilayer files yet… will be worked on!
Internally the file is organized in three levels:

  • Layers (user defined names, max 19 characters)
  • Passes (defined by enabling passes in RenderLayer panel)
  • Channels (R, G, B, A, X, Y, Z, U, V, W)
    When Compositing was enabled in Blender, the composite result is written in an own layer.

http://www.blender.org/development/release-logs/blender-243/imaging/

8

Much appreciated.

I saw that link earlier today, but thought that maybe some new development have happened since 2.43. I’ll try and dig some information out about what’s happening on that front.