Adjusting the scan settings can help you improve your scan results in most conditions.
The Scan Settings are available on the right-hand side of the Scan Dialog when you are about to take a scan. To take a new scan, start a new project or click Edit > New Scan in the toolbar.
HDR
This setting controls the camera's exposure range during scanning and is similar to exposure bracketing.
Example
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HDR off |
2 exposures |
3 exposures |
This scene has very high contrast (black and white) and requires the "3 exposure" setting to capture the entire scene without holes. With 2 exposures, and even more so with HDR off, the scan can not detect some of the darker parts of the scene.
Recommendation
- "2 Exposures" is the default and typically provides good results without requiring as much scanning time as "3 exposures" below. Try this setting first, then decide if it should be changed.
- "3 Exposures" should be used if your scene has very dark or high contrast materials (like the "It's Lit" poster).
- "HDR Off" should only be used if your scene materials have little/no contrast (e.g. an all-white sculpture), and/or you require faster scan times, as no HDR will result in a slightly faster scan.
Camera Mask
The camera mask allows you to manually select a region-of-interest within the camera image that the scan algorithm will focus on. Everything outside of the camera mask will be ignored. This is especially useful when your scene contains any shiny or reflective materials (or any other object type that will have trouble scanning).
Even if the projector is not illuminating these objects, but the camera can see them, they still can cause poor scan results. In these cases, you can use the camera mask to ensure that the pixels outside of the mask are not used when creating the scan image.
Example 1
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Camera image of scene with several materials not suitable for scanning (reflective glass, metals, and dark and shiny surfaces). |
Resulting scan, with no camera mask. |
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Applying the camera mask to the book only. |
Resulting scan, camera mask applied. |
Example 2
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Scene with a high contrast poster and a lot of ambient light on the left side. |
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Result without camera mask. |
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Same scene, applying camera mask to the entire projection region. |
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Result with a camera mask. |
Recommendation
- If your scene contains any glossy, reflective, or transparent materials, you should apply the camera mask to the region of the scene that you want to project on.
- If your scan contains significant noise or distortions, try applying a camera mask to the part of the scene you are interested in scanning.
- If a large portion of your scan is missing, you can likely fix this by manually placing a camera mask over the entire projected area.
Noise Reduction
The Noise Reduction checkbox will attempt to remove incorrect correspondences from the final scan result. Most scenes should not need this, but if your scene has reflective or shiny surfaces, enabling this option may result in a better scan. One downside is that the noise reduction algorithm may actually remove valid correspondence points, resulting in a scan with more holes, so use this option with caution.
Example
Camera image of the scene. Due to the shiny and dark materials of the bike, and the very thin features, this is a very difficult scene to scan.
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Scan without using the Noise Reduction option. |
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Scan with Noise Reduction enabled. There are still imperfections, but some of the inaccuracies and distortions are now removed. |
Recommendation
- If you notice distortions or incorrect colors/streaks in your scan, apply Noise Reduction to see if some of these issues can be removed.
- Since the noise reduction algorithm may remove valid points, only use this feature when necessary.
Smoothing
The Smoothing checkbox can be used to improve the quality of the resulting scan image, but may also cause distortions or wavy lines in scenes that have thin features or shiny materials. It is most useful for scanning flat objects, or heavily-textured materials.
Example 1
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Smoothing off |
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Smoothing off (close up)
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Smoothing on |
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Smoothing on (close up)
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Example 2
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Smoothing off |
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Smoothing on |
Example 3
Smoothing applied to a scene with many reflective materials and thin features. In these cases, smoothing can make the scan result much worse, and should not be used.
Recommendation
- Smoothing is most effective for flat objects (posters, wall art, tapestries, etc), especially if they contain text or sharp edges.
- Smoothing can cause distortions, especially in scenes that have shiny or reflective materials, so only use this feature when necessary.