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Hello

I've got a question concerning camera motion blur in rhino (with bongo). How do I control it?
What I usually did was rendering out animations without motion blur (motion blur disabled on the camera). But now I've got a pretty fast sequence where it does not look fluently:
https://vimeo.com/103813203

So I just enabled motion blur for the camera. But now the motion blur is extremely strong:
https://vimeo.com/103813201

I thought that maybe the shutter speed controls the motion blur strength, but when I change it, it has no affect.
So I am assuming that he calculates the camera distance between the two frames and makes the mblur between these two positions. Is that right?
This would mean there is not really a way to reduce it ...

Thanks
Christoph

My quick fix then would be to export the double amount of frames and render out only every second ... let's see how that works out
now, I only need to find out, how to render every second frame with the network monitor

Network aside, I don't think that will look right -- you should usually export and render as many frames per second, as you intend to have in the final animation. If you skip frames, it will indeed shorten the blur in each frame, but this will not look natural, since the blur will jump from one position to another, skipping the frames you did not render. Whether it might be acceptable, though, depends on the context.

But in filming, isn't the amount of motion blur defined by the shutter of the camera, not the amount of frames you are recording per second?
Otherwise you would have an 1/25 shutter which is quite a lot.

So I assume there is no other way to control it?

There isn't currently any other way. In Maxwell, the shutter only applies in terms of exposure; to regulate motion blur by shutter, I'd need to be able to move the camera an arbitrary distance along its path, while exporting any given frame. However, we react to the animation, we don't control it, so how it works is that when motion blur is enabled, I always record the last position exported, and then use it as the starting position, when exporting the next frame, such that you get blur based on the difference between the two.

Ok, thanks.
You were right: rendering out only every second frame does not look good as well ... Increasing the frame rate did, but that would mean a much higher rendering time

Another question concerning a still image I'd like to render out with motion blur:
Do you know if it possible to simplify this process? Right now, I have two cameras stored. First I export an MXS with the first camera, then switch to the second camera and start the rendering process.

Yes, if you open the plugin's Animation toolbar, you will find that you can set the initial position for a camera by right-clicking on the last button in the toolbar. If you then move the camera and render, the blur (the camera will now have motion blur enabled, if it did not previously) will be between the stored position, and the current position. The plugin uses this internally to support motion blur during animations; while inside an animation loop (whether it is begun by issuing the Maxwell_BeginAnimation command, or by the plugin detecting that an animation has been executed by other means), the plugin stores the current position for use in the next frame. The command name, if you want to use it in your own macro, is _Maxwell_SetCameraInitialPositionForMotionBlur.

ok great, thanks