Hi there we’re having weird results using a turn table and I’m sure we’re missing a simple step and thought you guys might be able to help us.
We seem to get good results when photographing a subject when walking around it (we’re using a Canon 6D), but when it comes to a turntable subject all the cameras seem to align from one direction rather than in a circular direction, see below.
We’ve turned GPS off on the camera, and have markers rotating with the subject, but can’t think why else this would be happening.
kkk… fill everything that is not the subject (on your photos) with a solid color.
the problem here is that RC uses ALSO the background to align your images… in the case of walking around the subject, the background changes… unlike in your turntable where all the background is static.
the actual subject is only on 10-15% of the sensor space, get closer or use zoom.
the captured subject looks like a plastic or fur toy, at least according to the images, that can be problematic with feature detection -> proper alignment
use some help for the alignment, put, say, newspaper under the subject to help the overall alignment quality.
Thanks guys, the plush toy was just a test piece, we’ll eventually be looking to do food shots for a client, ie see the banana below that was shot by walking around the banana (mind you that was only with 30 photos, so it was a rough test). The client wants about 400 food shots done, which we’re now thinking a QTVR approach might be better for time’s sake.
But for the future, we’ll definitely try filling the frame better and using the newspaper idea.
For objects with a weak texture it is recommended to group camera parameters. You can make RC to group camera parameters automatically using EXIF when images are add (set true to Application Settings\Import settings\Group calibration by exif) or you can trigger grouping by clicking “Group” button in “Inputs” panel which is opened, when you click on “Images” root in 1Ds.
To use a turntable is not so good idea because the photos do not have true disparity.
Maybe a good thing to move the camera 1 or 2 cm and take a new session and process the 2 session together.
I hope I an wrong (because it would make it more easy for me also)
I’m hoping to capture similar sized objects to the image attached using the turntable method. Obviously this image does not have sufficient lighting which i’m currently in the processing of sourcing, nor does it have an effective ‘featureless’ background required for the Photogrammetry process.
I’m in the process of sourcing a green screen but as far as I can work out I need a huge screen. The object is 6ft away from the back wall (a specified minimum distance to stop green spill onto the model) and the camera (Pi cam V2) is at a sufficient distance away from the object to ensure I get the full object in frame.
However as you can see these distances leave a huge amount of background space needing to be filled with the green screen, I calculate a screen size of 16ft x 16ft . My questions is this, if I used a green screen the same size as the grey wall on the image (which would obviously create a green floor too!) could I just crop each and all of my images to get rid of the unwanted background to the sides of the image? I’ve read that cropping the images pre-processing is a big no no but doesn’t explain why… As far as I can work out, as long as all images are cropped to the same size I don’t see why this would effect processing? Might be an extremely obvious reason why so apologies if it is!
I would just test it, but I don’t really want to buy a green screen if it turns out not to be big enough!
hey rfranks , i was going to start some photogrammtery for my client but i am unable to gaurantee my client for photorealistic reallt as my food photogrammy test are not going well even with simple burger
I placed my burger on tripod stand with small peice of circular white cardboard then I rotate around the object and having flash off apperture f/6 but images were not allign i took 30-40 photos to cover 360 degree
If you have expeirence in food photogrammy then brother please tell me also how to do food photogrammerty for pastas and any liquid dishes
