Tracker Motion Blur (possible bug)

Just after I managed to convince everyone around me that the motion blur in Fusion 8 is awesome... I can't seem to make it work anymore.

I'm using the built in motion blur from a tracker. Both the motion blur checkbox (from the tracker control area) and the MB (next to the playhead) are enabled.

Is there some other option that I might have accidentally switched off?

I've been playing around with the composition and found out that if you add a Transform node before the Tracker, the Motion Blur basically no longer works.


A bug maybe?

(kind of a lonely conversation here, isn't it?)

That's weird to say the least. And it's a lonely conversation, because there is not much to respond to.
Maybe if you add a comp or show us a screengrab or something then it would be easier to offer some helpful response. With the amount of info you provided all I can say is: mmm...strange, it should work.

I don't see what more info I could give you, Sander.

Have you tried the node setup I've attached above?

Works fine for me.

A screengrab of the setup doesn't help me, since I can't see your actual settings in my copy of Fusion.
I've used this setup many times before and it should work. So there must be something in your comp that makes it behave the wrong way. If you select all tools in your comp, copy and then paste in a reply on this forum inside of the 'code' formatting blocks, you can share the actual comp. Which is much more info that you can give me

I don't see what more info I could give you, Sander.

Have you tried the node setup I've attached above?

Great tip, Sander!

I've added the comp in pastebin to avoid flooding the thread with code: http://pastebin.com/i6XuuHjb

Now, I'm really curious to see if you get the same error.

Don't worry about flooding the thread. That's what the code button is for. It will put all the code in a small window. And this way it's not dependent on a 3rd party website.

I think I've found the 'bug'.
You're using corner positioning in the tracker. This is something that doesn't work with Fusion's concatenation. If you check the box 'flatten transform' in the transform tool it will work the way you expected it to. If you use the 'matchmove' option in the tracker, there is no need to check this and the tracker will do all motion blur the way you expected it in the first place.

Nice find! Unfortunately, I couldn't find too much info about concatenation in the manual. But, I'll keep this in mind next time.

Thanks, Sander!

As far as I know concatenation means that the actual modification of pixels in transformations will be done only once at the end of the chain of operations to preserve image quality.

See the following example:

Code: Select all

{
   Tools = ordered() {
      Transform1 = Transform {
         Inputs = {
            Center = Input { Value = { 0.45, 0.5, }, },
            Size = Input { Value = 0.1, },
            Input = Input {
               SourceOp = "Text1",
               Source = "Output",
            },
         },
         ViewInfo = OperatorInfo { Pos = { 212, 20, }, },
      },
      Text1 = TextPlus {
         Inputs = {
            GlobalOut = Input { Value = 100, },
            Width = Input { Value = 960, },
            Height = Input { Value = 1080, },
            ["Gamut.SLogVersion"] = Input { Value = FuID { "SLog2", }, },
            Font = Input { Value = "Arial", },
            StyledText = Input { Value = "CONCATENATED TRANSFORM", },
            Style = Input { Value = "Bold", },
            ManualFontKerningPlacement = Input {
               Value = StyledText {
                  Array = {
                  },
                  Value = "",
               },
            },
            ShadingGradient1 = Input {
               Value = Gradient {
                  Colors = {
                     [0] = { 0, 0, 0, 1, },
                     [1] = { 1, 1, 1, 1, },
                  },
               },
            },
            RenderToDPTFile = Input { Disabled = true, },
            DPTType = Input { Disabled = true, },
            DPTResolution = Input { Disabled = true, },
         },
         ViewInfo = OperatorInfo { Pos = { 55, 15.5, }, },
      },
      Transform2 = Transform {
         CtrlWZoom = false,
         Inputs = {
            Size = Input {
               SourceOp = "Transform2Size",
               Source = "Value",
            },
            Input = Input {
               SourceOp = "Merge1",
               Source = "Output",
            },
         },
         ViewInfo = OperatorInfo { Pos = { 582, 74, }, },
      },
      Transform2Size = BezierSpline {
         SplineColor = { Red = 225, Green = 0, Blue = 225, },
         NameSet = true,
         KeyFrames = {
            [0] = { 1, RH = { 33.3333333333333, 2.33333333333333, }, Flags = { Linear = true, }, },
            [100] = { 5, LH = { 66.6666666666667, 3.66666666666667, }, Flags = { Linear = true, }, },
         },
      },
      Merge1 = Merge {
         Inputs = {
            Background = Input {
               SourceOp = "Transform1_1",
               Source = "Output",
            },
            Foreground = Input {
               SourceOp = "Transform1",
               Source = "Output",
            },
            PerformDepthMerge = Input { Value = 0, },
         },
         ViewInfo = OperatorInfo { Pos = { 472, 74, }, },
      },
      Transform1_1 = Transform {
         Inputs = {
            Center = Input { Value = { 0.55, 0.5, }, },
            Size = Input { Value = 0.1, },
            FlattenTransform = Input { Value = 1, },
            Input = Input {
               SourceOp = "Text1_1",
               Source = "Output",
            },
         },
         ViewInfo = OperatorInfo { Pos = { 218, 95, }, },
      },
      Text1_1 = TextPlus {
         Inputs = {
            GlobalOut = Input { Value = 100, },
            Width = Input { Value = 960, },
            Height = Input { Value = 1080, },
            ["Gamut.SLogVersion"] = Input { Value = FuID { "SLog2", }, },
            Font = Input { Value = "Arial", },
            StyledText = Input { Value = "FLATTENED TRANSFORM", },
            Style = Input { Value = "Bold", },
            ManualFontKerningPlacement = Input {
               Value = StyledText {
                  Array = {
                  },
                  Value = "",
               },
            },
            ShadingGradient1 = Input {
               Value = Gradient {
                  Colors = {
                     [0] = { 0, 0, 0, 1, },
                     [1] = { 1, 1, 1, 1, },
                  },
               },
            },
            RenderToDPTFile = Input { Disabled = true, },
            DPTType = Input { Disabled = true, },
            DPTResolution = Input { Disabled = true, },
         },
         ViewInfo = OperatorInfo { Pos = { 51, 102.5, }, },
      },
   },
}