Monday, February 20, 2017

Photogrammetry for Photorealism

Photogrammetry is an emerging cutting-edge technology which creates photorealistic, highly detailed 3D models from photographs. Photogrammetry has a wide range of applications, from visual effects to engineering. Thanks to being highly detailed and photorealistic, models built with it meet the strict requirements of professional animation studios - face and body capture, are among the most in-demand. With Photogrammetry, many (sometimes hundreds) of digital images are processed by software programs which align them all, creating a thick point cloud. From there we build a mesh and ultimately a 3D photorealistic model. Micro-detail is possible in Photogrammetry if you really manipulate the environment for maximum results. For example, the camera settings insofar as the lens, the focal distance the aperture, shutter speed, ISO, and metering mode affect the photos dramatically, so there are many pitfalls to watch out for. Since Photogrammetry relies on very high-quality photos, it’s important to zoom in and analyze the pictures to ensure that the sharpness window is suitable.

3D photogrammetry model of our expert scan-tech Ken James.

In addition to the camera settings, the angle in which the camera is positioned via tripod (or hand-held) is calculated and very specific, and will vary depending on the shape you are capturing. So although the concept is simple, the capture session requires planning and the technicians must have ample experience to handle the session in expert fashion to attain the full potential of the project.

Similar to a Lidar scan, Photogrammetry can likewise be a suitable method for capturing buildings. An advantage for using Photogrammetry rather than Lidar is that the high-quality texture maps have a 1:1 ratio of surface to texture; much higher than does Lidar. Challenges that arise with Photogrammetry include maintaining consistent lighting during outdoor shoots. Geographic locations also play a part since some locations simply have better light from the sun. Regardless, an experienced team can iron out any problems.

3D Photogrammetry models of the historic Point Fermin Lighthouse in San Pedro, CA.

Cars and vehicles are great subjects for Photogrammetry since they are static, thus eliminating noise. Shiny surfaces can pose problems with traditional 3D scanning methods, but Photogrammetry can dodge the noise by utilizing appropriate lighting conditions.

TNG Visual Effect's Photogrammetry can be seen in this Campbell's Soup
Well Yes! commercial.

One of our favorite recent projects was delivering extremely realistic assets with Photogrammetry for the new Campbell's Soups Well Yes! brand of soups. The campaign features the soup's fresh, healthy ingredients so capturing the freshness aspect was key.We prepared for the assignment by picking up a different vegetable or fruit from the grocery store every morning to practice, and the finished :30 turned out great (Man vs. Machine, a design and motion studio, created the kaleidoscope effect).

Photogrammetry has an unlimited amount of applications and is fast becoming a go-to technique. Call us with any questions, regarding this or any 3D scanning technique and what would work best for your 3D scanning project.

Friday, February 3, 2017

LiDAR Scanning for the Big Jobs

Three-dimensional scanning has its challenges, some techniques more than others. LiDAR (light radar) scanning is a technology used to 3D scan larger subjects like elephants, planes, trains, automobiles, buildings, sets, and environments. LiDAR would also be used to scan natural areas like parks, woods, or a gravel pit for a scene. With this technique, we are able to quickly capture an incredible amount of data quickly and accurately.

There are some challenges we face when using LiDAR for entertainment projects. For example, cars are a popular item to scan using LiDAR. Since the surface is shiny we have to dull it down to avoid getting big areas of reflection which will not capture the scan data. Chrome and also has this effect.

Transparent surfaces like windows do not reflect back at all and require treatment with paint or applying a covering of paper or wax to show where the window is and the curvature. Another challenge with LiDAR is movement. Say that you would like to have a boat scanned with LiDAR while it is in the water. The rocking of the boat would make that scanning session difficult. A remedy would be to get the boat onto land or a barge in order to scan it. Another solution would be to tie it down tightly between two docks, in calm water.

Scanning buildings and environments in populated areas will pose certain challenges due to people moving about within the targeted scan area. In these cases, we block off the area if possible. Windows and shiny surfaces need to be accounted for again and prepared, in addition to staying safe in a live action area with moving cars, trucks, and buses.

While in active development it's easy to plan ahead for these considerations, once you know about them. In cases when we are surprised with challenges we are usually able to iron out a solution using some grit and determination, a benefit gleaned from 25 years in the 3D scanning business.