- 3,575
- Vancouver, BC
- Falango
These findings are as a result of the debate going on at this thread. I have used a 2007 Subaru STi that I built in 3D previously for the test. What I wanted to know was where are the cameras positioned EXACTLY. I have used 2 pictures taken of the demos seen in stores in the US. The pictures are not ideal for the test, but they are good enough. The grid you see in front of the car is there for ground plane purposes, to basically put the camera exactly where it should be in relation to the ground and the car. Here's what I found.
First test was the 'hood cam'.
Second test is the 'roof cam'.
I thought that the hood cam was too high to be a true hood cam. I thought it would have been placed a bit more forward based on what we've seen, but to do that, it would be pointing downward quite a bit to see as much of the hood as we see. I think the hood cam should be forward a bit, right in the windshield basically, down at, or a touch below drivers eye level. If it's too low, it will be too hard to get a sense for car position near walls and other cars. Too high, and well, we get what we have.
To be able to be even more accurate, if someone could provide me with the following, even from all camera views, I can recreate them all in perfect position with the exact focal lengths. I believe PD is using 35mm from my tests, but this will help me find this out for sure:
- Pictures of the screen from straight on, camera at the level of the TV
- Flat, straight section of track, pointing right down the middle
- Picture from each camera view
Big thanks to JDMKING13 for the pics!
-----------EDIT-----------
Alright, I went at it once more with the Stingray at Indy. I used it since it's proportions are closer to the Subaru STi model than the SLR or the 458. I think it proved something though. The roof cam matched pretty close to the one I had after using the Jeff Gordon stock car. The bumper cam is as follows:
How did I figure this out? After positioning the roof cam in relation to the car, I was able to put down some quick geometry for the track, walls, and brick start/finish line. Once I had that in position, I could use a new camera that had the bumper cam picture projected, and move the camera until the geometry lined up perfectly with that. I moved some edges to line up with the dark lines down the track to make it easier. There you have it!
First test was the 'hood cam'.
Second test is the 'roof cam'.
I thought that the hood cam was too high to be a true hood cam. I thought it would have been placed a bit more forward based on what we've seen, but to do that, it would be pointing downward quite a bit to see as much of the hood as we see. I think the hood cam should be forward a bit, right in the windshield basically, down at, or a touch below drivers eye level. If it's too low, it will be too hard to get a sense for car position near walls and other cars. Too high, and well, we get what we have.
To be able to be even more accurate, if someone could provide me with the following, even from all camera views, I can recreate them all in perfect position with the exact focal lengths. I believe PD is using 35mm from my tests, but this will help me find this out for sure:
- Pictures of the screen from straight on, camera at the level of the TV
- Flat, straight section of track, pointing right down the middle
- Picture from each camera view
Big thanks to JDMKING13 for the pics!
-----------EDIT-----------
Alright, I went at it once more with the Stingray at Indy. I used it since it's proportions are closer to the Subaru STi model than the SLR or the 458. I think it proved something though. The roof cam matched pretty close to the one I had after using the Jeff Gordon stock car. The bumper cam is as follows:
How did I figure this out? After positioning the roof cam in relation to the car, I was able to put down some quick geometry for the track, walls, and brick start/finish line. Once I had that in position, I could use a new camera that had the bumper cam picture projected, and move the camera until the geometry lined up perfectly with that. I moved some edges to line up with the dark lines down the track to make it easier. There you have it!
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great stuff, glad there is still things to think about even after all this time
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