Blur expression to eliminate flicker during moves on hi-res stills

[Steve Roberts]

Don’t forget, we can tie any value or variable to a slider for ease of, er, adjustment. Such as blurfactor.

I wish I had more time to futz with expressions.

[Sam Moulton]

I can get the first to work, the second for me gives me a blur that changes over time as you say but it has a max value of 30 not 5. Maybe i copied something wrong or am misunderstanding what you did. your expression is much more complex than anything i can cume up with at this time. if it isn’t in the list of expression goodies in the popup or made with a pickwhip i’m pretty lost.

I added a slider to my moving layer and tied to the expression with a pickwhip. the new expression is

L = position;
b = effect(“Slider Control”)(“Slider”)*.01;
L.speed*b

this means if the layer is moving 400 pixel per second, the blur is 4 pixels with the slider set to 4. i multiplied by .01 instead if deviding by 100 to aviod a divide by 0 error. the slider makes it easy to adjust. wow, i’m impressed with myself for comming up with an expression for this. it actually came from another project where we were measuring the speed of a point that was tracked going through the frame and converting that to mph.

[Colin Braley]

Sam,
you made me notice I did make a mistake in my second expression. I looked back at the second expression I posted and you’re right changing “maxBlur” won’t do anything. Change “amp” around to change the amount of blur. I had started the second expression using the first as a guide, and I guess I just forgot to delete the “maxBlur” variable. Think of the second expression like this: blur will go up and down from 0 to amp over and over again. How fast the layer is moving controls how quickly the blur will go up and down. I like your idea of measutring the speed of a point to get mph, neat idea. And also, If you didvide by 100 instead of multiplying by .01 I think your expression will behave the same. A “Divide by zero error” occurs anytime the denominator of a fraction is zero.
~Colin

[Bausdtown]

The expression-stuff sounds pretty complicatet. I just use an “Einstellungsebene”, don’t remember the english word right now. It’s a layer, where I can put effects on, that are then used in the layers below.

Then I use the reduce flicker filter (normaly with 0.6 or 0.7).
So you have a constant ficker-reduction and the image doesn’t get blurry, if you zoom in.

—-
No nation – no border!
Fight Law & Order!