When creating 3D models from photographs, taking the photos is more than half the battle! Here are some tips and tricks to make your processing a breeze.
Having the right equipment will greatly speed up your processing time. Fortunately, in today's world nearly any camera is good enough to take your photos. A few things to keep in mind:
Use a camera with at least 5 MPix resolution
Avoid ultra-wide angle and fish-eye lenses if possible (it is possible to compensate for these effects, but better to not worry about it)
Fixed lenses are preferred, if possible, but using a zoom lens is fine as long as you stick with one focal length (that is, don't change the zoom levels during the photo-taking process)
If you are making models of objects, some bonus equipment may prove helpful, even if it is not required:
A lightbox may be used to spread even, diffuse light across the object being modeled, helping to avoid the effects of shadows (see Environment below)
A turntable will rotate an object so you can get pictures of all sides, in case you don't have the room to move around the object. The lightbox available in the digital studio has marks at around 10-degree intervals, allowing you to rotate evenly around the object and know where you began and ended.
A tripod keeps your camera steady at various angles, and will make the process of using a turntable smoother.
Each of these items is available in the O'Neill Digital Studio for you to reserve in the space.
The environment in which you take the photos is almost as important as the equipment you use. Here are a few things to think about, whether you are taking photos of a fixed feature outdoors or in a controlled, indoor environment:
Shadows are bad; even, diffuse light is good. If you are working outdoors, a cloudy day is best, though this is obviously not always possible. If you are working inside, using a lightbox (see above) can help to avoid unwanted shadows
A consistent background color can be helpful, particularly if you end up needing to mask your photos during processing. Again, a lightbox can help with this. Otherwise, it is good practice to position your object in front of a consistent and contrasting backgroun.
Consistency is key, whether indoors or out. You don't want any objects or people moving around in the background of your images. This can confuse the processing software and make it more difficult to align your photos.
For successful 3D modeling of objects with photogrammetry, overlapping images are key, as the object itself is reconstructed through matching pixel groups across photos. Indeed, you ultimately want images of each face of an object from multiple angles in order to make your processing as simple as possible.
2 important notes!
(1) DO NOT ZOOM during the photo-taking process; stick with one focal length and, instead of zooming, move your body forward or backward as needed.
(2) In order to get the best model, try to fill up as much of the camera frame as possible with the object. You are making a model of the object after all, not the rest of the world.
The images below suggest a basic process for taking photos of a small object. It combines two factors for each photo, the angle at which the photo is taken and the rotation of the turntable on which the object is sitting. It is recommended to take photos at multiple angles of each side of the object, rotate the object ~10 degrees, and repeat the process until you have taken photos of the entire object.
If using a tripod, it may be easier to take all your photos at one angle and then rotate again at the second angle after adjusting the tripod.
Fewer photos may be required for simple objects, but we do recommend at least 30 photos for any photo-model to ensure that there is enough overlap for a full model to process
Check out the Digital Scholarship Sketchfab collection for the final results of the BC eagle model, created using ~100 photos (around 36 photos at 3 angles).
