Digital Light & Color

Some very nice multiple exposure effects can be created with the Motion Blur transformation if the blur path contains just a few of the small red circles. Instead of dragging your mouse to define a path, just click on each point you wish to have a displaced image generated. (After each click you do have to wait for a new image to be computed.)
It would be nice if larger displacements could be created. Currently the upper limit of the Strength slider is 200%. It would be helpful if this could be extended to 500%.
In general, it would also be nice if a displacement path could be edited. Control-click on a red circle to remove it would be helpful.

I increased the maximum strength to 500% for the next release.

Clicking in Motion Blur does not work the same way as for other transformations -- it does not add a control point, it just turns on a timer which samples the cursor location at regular intervals until you release the mouse button. Consequently, it may insert multiple control points at the same location depending on how long you hold the button down. Currently there is no quick way for me to add the ability to edit the path although it would of course be theoretically possible.

Thank you for the added range of Strength and the implicit warning to click very briefly if I aim to add a single sample point.

I found a relatively easy way to add the Shift-Click and Ctrl-Click features for the next release.

When I was checking updates on Motion Blur, I had a somewhat similar idea/reflection. When dragging the mouse, trying to maintain a straight, equidistant line of samples was a bit of a challenge. I was thinking of suggesting a way of drawing it automatically (define two end points and fill the middle or such) and also I was thinking of increasing the sampling frequency to make blur more realistic. But then I discovered (in Help) that one can draw multiple lines on top or near one another, and that more or less takes care of both suggestion already.