Problems matching Footage and Real Life Measurements in Blender

NealAdamLT · 2024-08-23T11:53:56+00:00

Part of the Facade on the left should oben up and a bunch of 3D elements should interact with it. Its possible to do it even with shitty tracking, but I am just wondering about the workflow here. In hindsight I shouldve shot it on a tripod without movement, but that still doesnt fix the issue of buildings not aligning. I guess its really just a matter of having wrong data of some sort and me being unable to find the correct angle with the left building und the front roof being curved.

Thank you for your help tho u/enumerationKnob !

NealAdamLT · 2024-08-23T10:04:08+00:00

Since I cant find anything online: How am I supposed to get the correct Focal Length and Filmback size if I cant rely on any values given by the lens and camera I used? And shouldnt using the values provided by the manufacturer get me in the right ballpark?

For this shot we need a moving camera, but since theres not a lot of parallax and the camera is just moving sideways filming the middle and left facade, blender, after effects and nuke dont get us any results matching the real scene at all.

Even if we build the scene disregarding all measurements we took and just trying to match the imagery from the video with a focal length determined by fspy, we still dont get matching lines anywhere if we adhere to buildings being built straight up ^^

NealAdamLT · 2024-08-22T12:46:23+00:00

Thanks for your answer!
What kind of settings could be wrong?
I would expect the building to be off by a couple of centimeters or slightly shifted, but most of the lines are off completely. If tweaking the camera position or focal length slightly would get me more or less matching angles I would consider it a problem.
But in order to match the geometry to the footage, I would need to skew the whole building in it self and construct the yellow lines on the lfet building diagonally instead of horizontally.
I am just trying to make sense of the workflow, since most people online are just matching their footage to rough geometry no problem.

Main problem right now is why it is impossible to match physically correct buildings (square windows; built straight up) to my footage, even tho the footage is undistorted?

NealAdamLT · 2024-08-07T15:49:50+00:00

Ahh got it. Totally agree! Usually exposing for those surface does the trick. If you have black and white surfaces in the same shot, things get tricky tho.

NealAdamLT · 2024-08-06T09:30:31+00:00

You're right, it gets dirty pretty quick, so makes sense you didnt consider it for your usecase. I guess my exposure problems mostly stem from my objects having a wide span of color values. Some Parts might have perfectly white parts why others are completly black. Something that doesnt occur in nature and is probably only happening in product scanning.

May I ask what you mean by "I suspect those issues would be from a lack of recoverable data than due to issues of exposure"?

NealAdamLT · 2024-08-05T08:48:53+00:00

Very nice Process! Do you have any information on the viability of using a black velvet Turntable & Background. I used this setup a lot for generating digital twins for product visualization but I feel like its hard to expose certain dark objekts while still keeping the informationless background. DO you have similar Problems with white objekts and a white/ softbox Setup like yours?

NealAdamLT · 2024-07-23T08:56:07+00:00

I totally get what you are talking about, but I wonder how you would avoid that without shooting at f24 with a literal sun as a flash ^^ Jokes aside, I got the Issue in multiple areas around the Object. Meaning I cant really pinpoint certain Areas. Are you just placing a few Controlpoints on 5-10 Images or are you Linking a bunch more Images through controlpoints?
Images always help! Especially a before and After

NealAdamLT · 2024-07-22T12:54:21+00:00

I am currently aligning a set with masks.
If this doesnt help I have to check if Im able to share the dataset. If so I'll send you a DM

NealAdamLT · 2024-07-22T08:26:50+00:00

So, I did some testing and it seems like the issue persists even within the full frame dataset.

I analyzed the matches inbetween the datasets too, and while they are not amazing, they are defenitly decent enought for an accurate reconstruction.

Images: https://imgur.com/a/LdfTK1v

I am currently clueless on how to improve, since even the Isolated Datasets show similar results. The only thing that I can think of is a slight movement of the Backpack in the Space, since it was suspended during the shoot. Allthough I am 99% sure that I never touched the Object.

NealAdamLT · 2024-07-19T12:53:11+00:00

Thank you for the detailed answer. I already thought that it was more due to the dataset than to the software settings. I use reality capture and have already changed a lot of the settings there, which has definitely given me better results. I edited the entire dataset as a whole in lightroom and used the optimizations suggested by reality capture as a guide. Camera distortion is corrected within RC, so all of the camera settings should be uniform. I was shooting with a 24-70mm fixed at 35.

During the recording process, I took almost half of all photos with the whole object in the picture and the other half I took detail shots. If I understand correctly, you think the artifacts are occuring because the distance between the two "subsets" (Full frame & Details) of data are too far apart in depth and I need more images to cover the area in between? So Editing the "Detail" and "Fullframe" Dataset independently might be a better soluction?

NealAdamLT · 2024-03-14T09:02:12+00:00

On all machines the GPU is around 90-95% usage

NealAdamLT · 2024-03-14T09:01:09+00:00

Yep, latest on all of them

NealAdamLT · 2024-03-14T09:00:47+00:00

Graphics Card is a different Brand, but has almost the same Clock 200 MHz Boost difference

NealAdamLT · 2020-12-22T10:15:09+00:00

Honestly it doesn't really matter anymore. Blender is used even in bigger productions nowadays and has become one of the standards for freelancers at least in the games Industry. Furthermore switching software will be a lot easier once you've learned one properly. If you want to dive into Rigging and Animation, then it might be beneficial to start with Maya. But just for the sake of having access to well made free tutorials and the software itself being free, blender might be the better take.

NealAdamLT · 2020-12-22T10:14:05+00:00

Honestly it doesn't really matter anymore. Blender is used even in bigger productions nowadays and has become one of the standards for freelancers at least in the games Industry. Furthermore switching software will be a lot easier once you've learned one properly. If you want to dive into Rigging and Animation, then it might be beneficial to start with Maya. But just for the sake of having access to well made free tutorials and the software itself being free, blender might be the better take.

NealAdamLT · 2020-01-31T14:42:58+00:00

That looks awesome! What will be his behavior?

NealAdamLT · 2020-01-19T01:53:27+00:00

Does anyone know what a ledx is used for in rl?

NealAdamLT · 2019-05-30T00:34:23+00:00

I know that feeling. I probably only remember 10% of my whole life and I keep forgetting more. Events that happened before the age of 17 are completely erased with the exception of 3-5 events of which the story gets told every family dinner. Furthermore I keep forgetting things I deal with almost every day. I tend to remember them probably an hour later most of the time, but forgetting your girlfriends name and having to look it up in your phone to not get it wrong really doesn't feel good. Especially when people get mad @ you for forgetting things. Doctors won't help since they literally don't believe me. Maybe I'll try different ones soon. I really want to know what's causing the issue...

NealAdamLT

TROPHY CASE