matching speed graphs

[dmiraie]

I'm not sure what's going on here.. but I need to match this graph (below)

with this one (below)

...but when I insert a keyframe (in the first graph), it turns into this (below)..

??

[Roei Tzoref]

when I insert a keyframe

how are you inserting the keyframe? specify the exact steps you are taking

[dmiraie]

I navigate to the same timeline position as the second graph's keyframe, and then click the add/remove keyframe icon.. i also tried the pen tool with the same result..

[Roei Tzoref]

I can't reproduce this in my system. try with a new layer and see when does this happen. if you can screen capture what you are doing this would help to examine what exactly is going on. make sure the whole U.I interface is clear

[dmiraie]

Does this help?

[Roei Tzoref]

Does this help?

yes I see now. you are manipulating the mask path in the graph editor and that's why you are seeing these results.

maybe Rick can explain this better but the mask path is a different parameter than probably any other in Ae because it does not have coordinates in ae, and alternatively, a true representation in the graph editor. because there are no coordinates for where the path is and what it is doing, you are left to use just the speed graph and even the speed graph will be only partly effective. take this example how the speed graph can "lie" - you can take two exact same path keyframes and easy ease them and see a curve in the graph editor even if there is no movement. the conclusion is that you are left to go partly "blind" in the graph when it comes to graph editor. sometimes and adjust accordingly.

[Horshack]

Roei Tzoref​​ is correct, mask shapes have their own coordinates, which are usually hidden from the user. However you can actually see the coordinates of the bounding-box around a mask shape by clicking on "Shape.." next to "Mask Path" in the timeline. From there you can modify the Left/Right coordinates in tandem to set relocate the horizontal position of the mask and the Top/Bottom coordinates in tandem to relocate the vertical position of the mask. So if you'd like to move a mask shape to the same position as the Position value of another item, look at the x,y of that other item and then click "Shape.." of your mask path and adjust the Left/Right and Top/Bottom values in tandem. For example, if Left is 10 and right is 50 and you want to move the mask path to horizontal position 100, then set the Left value to 110 and the right value to 150. Keep in mind that the coordinates are relative to the anchor so you may need to subtract instead of add depending on the coordinate system.

This is actually much easier to do in a script. I wrote one that does this but I don't have access to that system right now.

[Roei Tzoref]

Meant to write: the conclusion is that you are partly "blind" in the graph editor when it comes to mask (or shape) bezier paths. You can adjust the speed curve between the keyframes, but Ae doesn't take into account where these keyframes are in space. It will adjust the speed in time between values without knowing what they are and that's a different graph behaviour than probably any other parameter in Ae. That's why you see a "split" in speed even if there visually is not.

[Rick Gerard · Accepted solution]

It's a temporal interpolation problem. I am assuming that the layer is traveling in a certain direction at a certain speed and when you inserted the keyframe and changed position. Now the layer changes direction so it has to change speed. Cropped screenshots are of little use in diagnosing problems. If we could see the entire UI, the motion path of the layer, and the modified properties of the layer giving you problems it would be a lot easier to tell what's going on. We also don't have any idea what you are doing with the new keyframe or what type it is. Without at least showing the reference graph in the graph editor there is no way to tell what you are doing. See how much more info is in this screenshot:

Create single movement between two keyframes for position and then just select the pen tool and add a new keyframe in the speed graph and you shouldn't have any change because you didn't change anything. Move a layer or change a value to add a keyframe and everything is going to change. That's normal. This is what happens to the graph when you change the motion path.

[angie_taylor]

An easy way to reset the Speed graph in situations like this is to right-click on the offending keyframe and choose Rove Accross Time. Then ease out the first keyframe, ease in the last and then use the influence handles to balance your curve.