reducing jitter on still image pans in AE...

[David J. Payne]

Martin,

I am just about to start the work so thought i'd check the thread one last time and up pops your reply!

I am very inexperienced in AE but I have applied motion blur (the same as directional blur?) and enabled it on the timeline but I cannot see where I can keyframe it as the picture I have applied it to has already been keyframed for the movement.

I also read that the shutter angle and shutter phase plays a part. I have left phase at 0 and changed shutter angle from 180 to 720 but both options still give light jittering just with a differing amount of blur.

I understand what you mean by the lack of real motion blur causing the problem as it was originally a still photo, however my AE skills seem to have let me down at a crucial stage!

I was also wondering if the mpeg conversion using mainconcept mpeg encoder is undoing all of the work I am doing in AE when creating the avi. For example what should I choose with field encoding (top first, bottom first, progressive frame) and should I use deinterlacing (if so top or bottom field?)

If it is not against the boards rules could you drop me a line on sales@rideoutproductions.co.uk as it might be a bit quicker than waiting for replies on here, but I am literally waiting for this to be sorted before I can begin the next 3 months work!


Many many thanks for your help so far.

David

[Martin Chab]

Hi David,
The motion blur is something completely different to the directional blur.
Forget the mo blur and apply a directional blur (found in effects>blur>directional blur), set the angle to the same direction of the movement and finally keyframe so the bigger the movement the bigger the amount of blur and going to zero when the movement stops (also keyframe the angle if the direction changes during the shot).
The encoder has nothing to do with this particular problem (the test I´ve made were with uncompressed output).
Try that and tell me the results (mine were very good)

All the best

Martin Chab

[David J. Payne]

Martin what kind of numerical value do you apply to your directional blur?

[Adam Clark]

it sounds like a 3:2 pull down type of artifact. what was the orginal source of the video footage? was it captured on film or at 23.976fps and go through telecine? what is the output fps of your project?

with this issue, you would not really see any artifact until the problematic footage was indeed changing over time, such as your pan. with this problem adding blurs would not help as the core issue still remains. do you see horizontal black lines in the footage?

[David J. Payne]

Adam,

the original background footage that seems to have the problem is a 7MP digital still. With 25fps video overlayed, the final output is also 25fps.

I actually gave Martin the original files for him to play around with and he claims it worked so I still have great hope for the directional blur!

David

[Ger Griffin]

in all the improvements and presets ae has developed it still hasnt conquered this problem since the beginning.
sometimes it works well, sometimes it doesent. i cant seem to lock down the reason.
it could be colours. try tinting the image to a few different shades and see if that affects it.
less zoom and pan is the obvious answer if you can get away with it & directional blur doesnt work.
keep up informed david.

[Ger Griffin]

sorry keep us informed

[Ger Griffin]

just thinkin here,
if the directional blur or anything else dosent work (the blur may soften the image too much) why dont you render out the clip at say 3 times slower than you need it, or 4 times slower to get it nice and smooth. then speed that clip up x3 or x4 in your NLE - ........... could work .........

[Martin Chab]

Hi David,
The numeric value for the directional blur would be different for each footage and animation speed. That means that you dial zero at no movement keyframes and visually dial a number at the maximum displacement parts to cancel the jitter and let AE interpolate the inbetween. As I told you the result was quite good for me. I dont have internet at the studio but I will try to remember to make a copy of the result and post for you to see (may be I have also the AE project, let me see)

All the best

[Mark OConnell]

Have you tried just adding a 0.5 gaussian blur?

[Martin Chab]

Hi David,
Yesterday I made a new test (I forgot to copy to post but I will) that gave me a better result.

1. import the image to AE
2. drop the image to a new composition icon to make a full size comp
3. go to composition settings and dial the size of your final comp
4. adjust the scale of your image
5. go again to comp settings and dial a number that allow you to see the full picture (a big number)
6. ctrl-d (duplicate) the layer two times
7. on the top layer put the following effects:
find edges
hue-saturation (turn the saturation all way down)
minimax (operation: minimum, size: around 4, direction: both hor and vert)
gaussian blur (around 3 will do)
8. precompose the top layer moving all the attributes
9. set the trck mode of the second layer to luma inverted matte
10. set the parenting of the top and bottom layers to the middle layer
11. go to comp settings and dial the size of your final comp
12. put a directional blur on the middle layer
13. animate the middle layer keyframing the directional blur as you like (the other layers will follow as they are child of the middle layer)

In this way the directional blur only affects the edges and have no effect on the flat or soft areas that have no jitter.
The minimax radius controls how many pixels around the edges the comp will be blurred thats why the number will depend on the picture characteristics.

[David J. Payne]

Martin,

Thanks a lot. I tried that today and it does seem to have a good effect. Still not perfect but I would imagine I need to play with the settings and values a little bit more, however even if I stopped now the results would be much better than they were with the pan alone.

Thanks to all for their help.