By Steven Schain
ReCap is what is known as a reality capture program, allowing you to work with point clouds captured from a laser scanner or created from photographs. The use of photographs to create 3d geometry is known as photogrammetry. This uses an array of photos, taken from multiple angles around whatever object you are wanting to capture.
To demonstrate this functionality, I decided to take a quick set of photographs of the Vance Monument in Asheville, NC. This monument made a nice subject because I could get a good view of the entire perimeter. But, its main drawback is that it is a tall object, so all of my photos would have to be taken from the ground level.
This means that the top of the monument would not be able to have as much detail as the bottom because I could get much closer to the bottom of the monument than the top.
When taking photos for a ReCap project, try to take the photos as evenly spaced around the object as possible. You also want to take photos that are “overview” photos that show the entire project, and you want to take photos that progressively get closer, showing more detail. In this case, I tool about 130 photos at several distances from the monument.
When you begin working with ReCap, you will need to have a subscription to at least the standard version of Recap to create a model from photos. Once you log in, you are presented with the dashboard where all your projects are available. To begin, you select the Photo to 3D option from the dashboard.
The next step is to upload the images into the ReCap project. This can be easily accomplished by simply dragging and dropping all the photos into the browser where you see the Add Photos target.
Next, it’s on to Settings. Here you can decide the name of the project and adjust the quality and other options that will affect the result. When it comes to quality, there are two options, Preview and Ultra. Ultra takes longer to process, but provides a much higher level of model fidelity. However, this option can cost credits. Smart Cropping will try to remove background geometry that is not needed for the final mode. Smart Texturing uses more intelligent filtering to match multiple images to create a higher quality texture map. Nadir Optimization can be used if you have more detailed data such as GPS data. Finally, the output formats for output can be selected at the start. Keep in mind, you can export other formats later.
To begin the process of uploading the images to the cloud for processing, click Create.
When the processing is complete, you can enter the project from the dashboard. Here you can open the 3D model that was created, resubmit the project for reprocessing, modify your source images if you have new photos to further enhance the resulting model, and you can export the model. You can also share the project with others.
Clicking Open 3D Model lets you navigate around the generated model. Here you can verify the model and check for detail and usability.
If you notice that you need more detailed images of the part, you can retake more photos and resubmit the project to be processed again.
ReCap is an excellent tool for creating 3d models from a series of photographs that can be used for 3d animation or as a basis to remodel the object.
This article originally appeared in Issue 22 of The Blast. Sign up now to get the next issue delivered to your in-box.