Can't get a useable camera solve

Hello everyone, I upgraded to MOCHA PRO in November 2019 (Not sure what version that is). I am having an extremely difficult time getting a camera solve on almost ALL of the Green Screen footage we have from a big production. The shot is not that difficult BUT it does have some large parallax as we shot it using a Chapman on half-moon track. The majority of shots are just a track from left to right, right to left but some others involve craning up/down while tracking. Regardless of the scenario I cannot get a good camera solve. I did not have this issue with the previous version of Mocha Pro (2018). I have attached a screenshot of POINT A to POINT B from one of the clips. ANY help would be greatly appreciated.

Hi there. Nothing should have changed in Camera Solver from versions. Are you using Auto or selecting the specific camera solve parameters before solving. I am curious if you installed the older version if there is a difference.

How many tracked layers have you selected to solve? A good solve requires at least 3 non co-planar surfaces tracked and it is proper to align the surface to the plane you are tracking before solving camera. You bg seems to be on curved cyc, which coukd throw off solver. I would first try to track only specific track marks that are on the same relative plane and be careful to avoid the ones that are in different depth or curves.

I mocked up the areas I would track separately in this image. unnamed

When possibly group trackers on the same plane (for example the red would all be one layer using X+).

Hope this helps. If you want to send me the shot, I might have the time to look today…

Note - looking at my image closer, I think the green rectangle on right is another light rig and that should be on its own layer or excluded.

Thank you for the prompt reply. Yes I am doing basically what you have going here, multiple layers and tracking planes, setting the pixels to 90, large parallax and have tried AUTO and custom camera options, nothing I do seems to get me the results I need. The green screen is on a hard sike for a seemless background, so I have also tried creating layers for ground plan (what you have in red) and then one LEFT back wall and ONE RIGHT back wall and then using the C-Stands as my middle parallax points. The two C-Stands on both sides are to help establish a constant for depth and parallax as a fail safe. I’d be more than happy to send you the shot, bc again I cannot get a good useable camera solve and would be eager to see if you are able.

I should add that the elements on each side will go out of frame so I have to manually adjust the track points in those places in time.

It could be a challenge for Mocha’s solver. It sounds like you have a handle on the process and limitations. Moch’as solver is light compared to a dedicated solving app like Syntheyes or PFtrack.

I will DM you with my email.

It also sounds like you might be doing some manual corrections, from your last post, and that’s definitely going to throw the math off. Try trimming the layers where they go offscreen, and then add new layers in that stay onscreen. If you overlap those trimmed layers in the timeline you should get a better solve.

aahhhhh I see, and makes total sense. Let me try that. Thanks, I will try that and let you guys know.

That totally did the trick! Thank you so much for the assistance, I’m blown away by y’alls promptness, professionalism and genuine willingness to help. BORIS FX team you are top notch!

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Glad that Mary’s suggestion helped! The file you sent me does not seem to challenging and I am glad to know that there was no regression from previous versions of Mocha Pro.

We do hope to improve the camera solve interface and features in the future.

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Hello again! I figured I would keep this in the same thread. I am having a hell of a time getting a similar shot to track. IDK why but I just cannot get the surface plane to stay accurate, it is skewing super hard as the camera dolleys from one side to the other. Have tried turning on and off skew/perspective etc The dolley is on a half moon. See screen shots attached from point A to B. I get high 90’s % camera solve but lots of jitter and a lot of floor drifting

It’s almost certainly shadows, try to avoid them wherever you can. Make sure your holdout shapes are very generous.

hmmm ok i’ll give them some more wiggle room and be a little more selective in the tracking areas. I have never had this much trouble before! Do you recommend animating shapes before tracking or is trimming layers that go off screen a better technique for a shot like this? Lastly, there is quite a large parallax since we are moving almost 180º so I assume that the perspective and shear options should be selected.

Thanks for the help!

So I was able to get perfect tracks where the surface planes aren’t skewing to undesirable proportions by unlinking the shapes from layers. But the camera will not solve no matter what I try. I am using 3 seperate layers, one for the right wall, left wall and floor plane.

Have you tried solving for the lens curve in the lens module? I see a significant curve on the mic stand and wonder if that could be causing the problem. I hate to say it, but you have to retrack after a lens solve.

I haven’t done that no, let me try that and re-track evertyhing. thanks I will let you know how it goes.

I did the lens correction but that didn’t seem to fix anything…this is a tough one!

Okay I have one more thing for you to try. Can you also try tracking just with translation, scale, and rotation, the poles that are holding microphones or their bases and then adding those to the solve?

Ok I will try that

Dang, still a no go. Not sure what to try at this point.

I am unsure, it might be Mocha can’t get a proper solve for you on this shot and you might need to try another tool. We are one of many tools in the toolbox and while we would love to solve this for you, it might be that we don’t have enough data to do so. I would try other camera tracking options and seeing what you get.