[Ernesto]

I wonder what is motion Blur + Deformation.
In the on line manual I cannot find any detail. http://support.nextlimit.com/display/ma ... otion+Blur
I would like to know also what is Shutter Open Offset...

I wonder if this is the intended effect:



If so, that is interesting.
This effect happens even with advanced digital cameras that uses phisical shutters.
In low shutter speeds in Vertical plane shutters, of about 1/10 1/5 second, the upper or lower part of the frame (deppending on the type of shutter, is exposed a fraction of second before or after the other part of the frame.
this is used to enhace artistically the sensation of speed.

The variables are:
Vertical or horizontal plane shutters.
In case of Vertical plane shutter, movement from up to down, or from down to up.
In case of Horizontal plane shutters, movement from right to left or from left to right.
For both types: there will be a shutter speed (the time the film is exposed) and a movement speed (the time the shutter needs to move from opened to closed position. The combination of these two, determines the strength of the effect.

In the example of a famous image taken by the famous French photographer Jacques Henri Lartigue
http://es.wikipedia.org/wiki/Jacques_Henri_Lartigue
In this image you can see an interesting combination: The people in the background are inclined to the left, and the car to the right. The photographer used a vertical plane shutter camera which movement was from up to down, and he was moving the camera from letf to right, at a lower speed compared to the car speed, this results in those interesting deformations.



Ernesto

[Mihai]

From the page you linked to:

Motionblur + Deformation

Maxwell Render can calculate two types of motionblur: for the entire object and also for individual moving vertices of the object (deformation motionblur). As deformation motionblur needs more RAM when rendering (depending on the number of vertices the object has), and is only needed if the object actually deforms, you have the choice to activate only normal motion blur or also deformation motion blur.

So hopefully you find at least some detail in that explanation. If your entire object is moving, don't use deformation blur. If parts of your objects are moving individually, like a noise applied to the mesh which makes the individual vertices of the mesh move, then use deformation blur.

It has nothing to do with the effect you described above which is known as Rolling Shutter: http://en.wikipedia.org/wiki/Rolling_shutter

About Shutter open offset: http://support.nextlimit.com/display/ma ... otion+Blur

That info is conveniently (I hope!) placed in the section of the docs called Plugins>Maya>Maya Motion Blur.

[Ernesto]

Thanks Mihai, I see, it was totally diferent thing...
What about a car, I have cars with rotating wheels (through particles)
Is that considered deformation or not?

I find the on line documentation not easy to find... I would really prefer a full manual which could have certain continuity.
The on line documentation is from my viewpoint too much fragmented, so that you have to know previously what to look for, which was not my case.

Ernesto

[Mihai]

But you were actually on the page where I linked that paragraph from, yet you said you didn't find any detail....

The chapters on the left side are like chapters in a book or PDF. No change there in continuity compared to if this info was in a PDF, except that you have the miracle of efficient search which gives you a bunch of results, unlike a PDF word search, which sucks.

If I use the search box and start typing motion...the first page that appears in the suggestions below the search box as you type, is called "Maya motion blur" which should give some indication to you, since you were looking for info about motion blur, and you use Maya. The second page that appears in the list is the main page about Motion blur.

[Ernesto]

Yes, I saw it, but didn´t understood it. It is too short, and perhaps some more detail is needed to explain the feature.
I still wonder if a Car with moving (rotating) wheels should be considered Deformation or not.

E

[seghier]

try to create that with real camera
i think the photographer move his old camera to get this deformation

[Mihai]

I still wonder if a Car with moving (rotating) wheels should be considered Deformation or not.

If the wheels are separate objects and you animate them only by using rotation/translation, then no deformation blur is necessary and the render will be faster.

[seghier]

http://m43photo.blogspot.com/2010/12/gh ... ation.html

[Ernesto]

I still wonder if a Car with moving (rotating) wheels should be considered Deformation or not.

If the wheels are separate objects and you animate them only by using rotation/translation, then no deformation blur is necessary and the render will be faster.

Thank You very much!
E

[Ernesto]

try to create that with real camera
i think the photographer move his old camera to get this deformation

If you are interested, here you have a good explanation, and discussion on the matter:





http://www.largeformatphotography.info/ ... 3dabebbb29

Another similar old example:


But modern Iphones do the same thing:
http://www.todayandtomorrow.net/2009/01/21/propeller/

E

[Mihnea Balta]

Deformation motion blur is needed for deforming objects. This includes skinning. If you parent the wheels so that they inherit their rotation from something, you don't need deformation blur. If you bind the wheels to joints, you need deformation (even if it's a rigid bind). This is all explained on the page that Mihai linked. With pictures. So is shutter offset.

It's also very easy to try, and much faster than waiting for someone to answer on some forum. Render your image with movement-only blur. Are the wheels blurred? If yes, you're done. If not, turn on deformation blur. Are they blurred now? If yes, you need deformation blur. If not, your setup is wrong (wrong frame, wheels not actually moving, exposure or shutter angle too low).

[tom]

I think I understand what Ernesto says. I guess those old images show something related to traditional rotary shutter and moving film. Because unlike rendering, a moving film may register different moments of time per scanline captured on a same frame. Of course, that would also bend the image besides just adding the blur in motion. Same thing could happen in digital cameras if they process scanline prior to the whole frame, especially with a slow processor. So, the answer is clear. No, Maxwell does not compute (and I don't see this *usually unwanted* effect achieved by other render engines either) motion blur this way. Like every other software, it computes motion blur per frame, which is the correct way of doing it and I believe what you are showing is a mechanical limitation of the old technology. And hey! Ernesto, this has nothing to do with Motion Blur...

[Bubbaloo]

You could manually recreate this by creating an animation and rendering one frame for each vertical line of resolution.

Or you could use a skew modifier.

Whichever is easier.

[RichG]

I guess, in the same way that people use lens correction software to introduce chromatic aberration rather than remove it, you could use one of the rolling shutter plugins to introduce rolling shutter to a squared up render.