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[darksun48]

How is Syntheyes with stabilizing a locked off shot with no movement or a tripod shot with panning? In circumstances with no 3D information, either because it was on a tripod and I need to stabilize a few bumps, or handheld with no translation, how well can SE stabilize it, specifically in regard to perspective change / keystoning with shaking?

Would the appropriate method be to solve in tripod mode to obtain the fov and stabilize then? The shots I'm thinking of were on a tripod, but there were a few small bumps and a 2D stabilization in After Effects wasn't effective because of the perspective change, which is something SE handles great with moving shots. I've only used SE to stabilize moving shots so far, and just wanted some feedback of whether I'm barking up the wrong tree here or not before I start pursuing it.

I guess I'm asking if there are any good techniques to stabilize a tripod or handheld shot without movement or with a tripod pan, where a 2D stabilization wasn't enough due to perspective change. I know I can use AE's warp stabilizer but there's no control there and I prefer using SE for keystone corrections. Thanks for the thoughts.

[GraphicsKid]

All syntheyes stabilization does is smooth out the pan/tilt/roll of a shot. It doesn't magically make a jittery camera move smooth. In order for the stabilization to work, your first need to solve the shot.

[darksun48]

Thanks for the response. I understand. To be clear, my question relates specifically to shots that aren't camera moves, but are in place on a tripod, or don't move in 3D space when handheld. I get that there isn't a magic wand here; I suppose I just want to know if people are using SE in this manner, or if they're relying on other software or other methods that are better suited for stabilizing non-moving shots, when there are small perspective changes that 2D stabilizing falls short on.

In your experience, how well does the stabilization work when solving a static shot or tripod shot, not a moving shot? Does it reliably help with small perspective change when the camera is not translating, like a small bump?

I'm hoping to get some feedback with more experienced users than myself, as my lack of experience using SE for nonmoving or tripod shots is the reason I'm asking this question. I want to know if this is even a good possibility before I work on learning how to do it reliably, or if there are better options. Thanks for your time and help, much appreciated.

[GraphicsKid]

Ok here's something I want to clear up real fast. You keep saying "a small perspective change when the camera isn't translating"... how is that possible? pan/tilt/roll is NOT a perspective change. Perspective changes occur ONLY when the focal point of the camera moves.

I like to think of it as a big picture-bubble around the camera, and the camera is only seeing a small slice of it. When you pan/tilt/roll, you are only seeing different parts of the bubble. When the camera physically moves, then you're looking at a slightly different bubble.

Stabilization in Syntheyes basically just spins this bubble around the camera to compensate for rough pan/tilt/roll moves. The only difference between the stabilization of say... After effects and the stabilization of Syntheyes is that Syntheyes has the focal length data, so it can properly ROTATE the layer around the camera, rather than just shifting the layer around in 2d space.

For very minor bumps, you can probably get away with just a 2d transformation to stabilize.

ON THE OTHER HAND THOUGH: any stabilization results in black bars on the edges of the frame where data has been lost. Syntheyes has tools built in to recreate the lost data ie by filling it in with data from previous frames.

[darksun48]

Yeah, I see I wasn't clear there in my explanation, sorry about that.

I have shots where, let's say, someone bumped the tripod, enough so that for a couple of frames the perspective did change slightly, then fell straight back into place, and I'd like to at least attempt to smooth these out a bit. A 2D stabilization then looks strange because for a brief moment, the perspective is slightly higher because the camera did move, ever so slightly, so when shifted down to compensate a bit it looks odd. I also have a couple of very steady handheld shots, where it isn't moving through space, per se, but slight movements up and down that I'd like to smooth out again are changes in perspective that look odd with a standard 2D position stabilization.

Thanks for your explanation, that's actually really helpful. It sounds to me like stabilization in SE should work fine in the above circumstances as long as I'm solving properly. When the bumps are small, 2D stabilization has been fine, but when the camera moves up or down enough and I'm trying to lock it in place it looks strange anchoring it in place.

[grabiller]

Hi,

Not sure if this would help but when you deal with nodal shots (what you call pan/tilt/roll), it's a good idea to also take a few still pictures of the set at various locations and with different angles.

This, of course, if you have the chance to be on the set when the shot was taken (or perhaps you may go back later and take pictures).

Then you can take advantage of SynthEyes multishots tracking feature by linking trackers from the actual shot to the trackers from the still images (used as one shot).

This way you should get a pretty good 3d solution despite the fact that the main shot was (mostly) nodal.

Once you got the 3d solution, you should be able to easily stabilze the shot as if it was a non-nodal shot.

Cheers,
Guy.
--
guy rabiller | radfac founder / ceo

[borgus]

hi grabiller,

yes, that's also good, but also always introduces some position jitter when
dealing with nodal pans.

Cheers,

Sebastian