How to Create Drone 3D Models in Polycam

Drone photogrammetry allows you to create detailed 3D models of landscapes, buildings, and large outdoor areas by capturing overlapping aerial photographs. This guide will walk you through the entire process, from planning your flight to processing your images in Polycam.

What You'll Need

• A drone capable of capturing high-quality photos and videos, with good wind resistance to prevent blurry images
• Sufficient battery power (plan for multiple batteries if covering large areas)
• A microSD card with adequate storage space

What You'll Get

After successfully completing your drone photogrammetry capture and processing in Polycam, you'll receive:

• 3D Model: A detailed, textured 3D mesh of your captured area that can be viewed, measured, and analyzed
• Measurements & Annotations: Ability to take distance, area, and volume measurements directly on your 3D model
• Shareable Links: Web-based links to view and share your 3D models with clients or team members
• Export Options: Models can be exported in various formats (OBJ, FBX, LAS, etc.) for use in other software

Flight Patterns and Capture Angles

Understanding Capture Angles: Nadir vs Oblique

The angle at which you capture images significantly impacts the quality and completeness of your 3D model. There are two primary capture angles to understand:

Nadir Captures (Straight Down)

Nadir images are taken with the camera pointing straight down at the ground. These captures are ideal for:

• Flat terrain and open areas
• Creating orthomosaic maps and top-down views
• Measuring horizontal distances and areas
• Agricultural or land surveying applications

Oblique Captures (Angled)

Oblique images are taken at an angle (typically 45-65 degrees from vertical) to capture both horizontal and vertical surfaces. These captures are ideal for:

• Buildings and structures with vertical elements
• Complex terrain with elevation changes
• Objects that need complete 3D representation
• Capturing details on walls, roofs, and vertical surfaces

Choosing Your Flight Pattern

The flight pattern determines how your drone moves across the area and where it captures images. Proper overlap between images is crucial for quality 3D reconstruction.

Interactive Flight Path Visualization

Watch how a properly planned mission captures complete coverage with adequate overlap:

Single Grid Pattern

Description: The drone flies back and forth in parallel lines across your area of interest, capturing images at regular intervals.

Best For: Simple, flat areas, quick surveys, or when you need a basic top-down view of the site.

Advantages:

• Fast and efficient flight time
• Easy to plan and execute
• Good for basic terrain documentation

Limitations:

• May miss details in complex terrain
• Can have gaps in coverage on slopes or varied terrain

Double Grid (Crosshatch) Pattern

Description: Two perpendicular single grids flown over the same area. For example, fly north-south, then fly east-west over the same site.

Best For: Professional mapping, detailed surveys, construction documentation, and sites requiring high accuracy.

Advantages:

• Significantly improves model accuracy and reduces distortion
• Provides redundant coverage from multiple angles
• Better captures features that might be hidden in shadows from one direction
• Reduces processing errors and produces more reliable measurements

Limitations:

• Requires approximately double the flight time and battery usage
• Generates twice as many images, increasing processing time
• More complex flight planning required

Circular/Orbit Pattern

Description: The drone flies in circles around a central point or object, keeping the camera angled toward the center. Multiple orbits at different altitudes can provide complete vertical coverage.

Best For: Individual structures, monuments, towers, buildings, or isolated objects that need 360-degree coverage.

Advantages:

• Captures all sides of a structure or object
• Excellent for vertical surfaces and architectural details
• Can combine multiple altitude levels for complete coverage
• Works well in confined spaces around a single subject

Limitations:

• Not suitable for large open areas or terrain mapping
• Requires careful distance and overlap planning between orbit positions

Facade Pattern

Description: The drone flies parallel to a building or vertical surface at multiple altitudes, capturing the facade from bottom to top. The camera is angled perpendicular to the surface, and the drone moves in horizontal passes at different heights.

Best For: Tall buildings, architectural facades, vertical structures, bridges, or any vertical surface requiring detailed documentation.

Advantages:

• Captures high-quality vertical surface detail
• Excellent for architectural documentation and inspection
• Provides consistent resolution across the entire facade
• Ideal for buildings taller than the typical drone flight altitude

Limitations:

• Only captures one side of a structure at a time
• Requires multiple facade patterns for complete building coverage
• May be challenging in areas with limited space to fly parallel to the building
• Requires careful planning to maintain a consistent distance from the facade

Flight Best Practices

Before diving into specific flight patterns, it's essential to understand the best practices for successful captures:

Weather and Lighting Conditions

• Optimal Lighting: Fly during early morning or late afternoon when lighting is soft and even. You will want to avoid harsh midday sun that creates dark shadows.
• Cloud Cover: We recommend scanning on overcast days as the clouds will diffuse sunlight and eliminate harsh shadows.
• Wind Conditions: Fly in calm conditions with minimal wind (under 15 mph is ideal). Strong winds cause image blur and make maintaining consistent flight paths difficult.
• Avoid Rain and Fog: Flying in hazardous conditions reduces visibility and the overall quality of the capture.

Flight Execution

• Fly Slowly: Slower flight speeds reduce motion blur and ensure proper image capture. Most automated flight apps handle this automatically.
• Capture Extra Perimeter Shots: Extend your flight pattern slightly beyond your area of interest to avoid edge artifacts in your final model.

Image Capture Best Review

• Use Maximum Resolution: Always shoot at your camera's highest resolution setting for the sharpest textures and best detail in your 3D model.
• Capture Plenty of Images: More images with higher overlap (75-80%) produces better results.
• Minimize Moving Objects: Try to fly when there are fewer cars, people, or other moving elements in your scene, as these can create artifacts in your model.
• Use JPEG Format: JPEG is the recommended format for most drone photogrammetry projects, and can be uploaded to Polycam.

Pre-Flight Checklist

• Battery Management: Have multiple fully charged batteries ready. Calculate flight time needed based on area size and always plan for a safety margin.
• Storage Space: Verify your SD card has sufficient space. A typical photogrammetry mission can generate hundreds of images, or several gigs worth of footage.
• Test First: If possible, do a small test capture and process it to verify your workflow before committing to a large project.
• Check Regulations: Verify you're compliant with local drone regulations, including airspace restrictions, line-of-sight requirements, and any necessary permits.

• Spot Check for Sharpness: Review a sample of 5-10 images on your device to check that they're in focus and not blurry.
• Verify Coverage: Check that your flight path covered the entire area of interest with no major gaps.
• Lighting Consistency: If your flight took a long time, check that the lighting remained consistent throughout the capture.

Drone Settings and Outputs to Look For

For successful photogrammetry and splats, you need proper camera settings and a solid understanding of your drone's output files

Camera Settings

• Image Format: Shoot in JPEG or RAW format for still images. Polycam also supports video capture for photogrammetry.
• Exposure: Use manual or automatic exposure, but avoid large exposure variations between images
• ISO Keep ISO as low as possible (100-400) to prevent noise in your images
• Shutter Speed: Use fast shutter speeds (1/500s or faster) to avoid motion blur. Remember, the faster the drone flys, the higher your shutter speed should be set.
• White Balance: Lock white balance to avoid color shifts between images

Image Metadata (EXIF Data)

Modern drones automatically embed important information in image files. Polycam uses this metadata, particularly GPS data, to georeference and scale your 3D model:

• GPS Coordinates: Latitude, longitude, and altitude data that Polycam uses to georeference your model and determine accurate scale
• Camera Parameters: Focal length, sensor size, and lens information
• Gimbal Orientation: Pitch, roll, and yaw data showing camera angle

Processing Images and Video in Polycam

Once you've captured your images or video, Polycam makes it easy to turn them into detailed 3D models.

1Prepare Your Images or Video

1. Transfer images or video from your drone's SD card to your computer or mobile device
2. Remove any blurry, overexposed, or otherwise problematic images
3. Organize files in a dedicated folder for your project

2Create a New Project in Polycam

1. In your Capture library on Polycam web, click the "Create" button
2. From the drop-down menu, select "Create model from images/videos"
3. Within the create window, click "Choose from file systems"
4. Select the video or images taken from your drone

3Choose Processing Type and Settings

Depending on your subscription, you can choose between two processing methods:

• Photogrammetry: Available for all users. Creates detailed 3D models using traditional photogrammetry algorithms.
• Gaussian Splat: Available for paid subscribers only. Creates highly detailed 3D models using advanced Gaussian splatting technology.

If you choose Photogrammetry, you'll select from these processing types:

• Optimized: Fastest processing, good for quick previews
• Medium: Balanced quality and processing time
• Full: High detail and accuracy (longer processing time)
• Raw: Maximum detail, preserves all captured data (longest processing time)

4Start Processing

1. Review your selected images or video to ensure they're all included
2. Click "Process" or "Start Processing"
3. Wait for processing to complete (this can take from minutes to several hours depending on the number of images or video length and quality settings)
4. Polycam will notify you when processing is complete

5Review and Refine Your Model

After processing, examine your 3D model:

• Check for holes or missing geometry (indicates insufficient image overlap)
• Look for texture quality and clarity
• Verify that the scale and orientation are correct
• Use Polycam's editing tools to crop unwanted areas or clean up the model

Common Issues and Solutions

Troubleshooting photogrammetry issues becomes easier when you understand the underlying causes. Issues are organized by category to help you quickly identify and resolve problems.

Image Quality Issues

Blurry or Low-Quality Textures

Possible Causes: Motion blur from slow shutter speed, camera movement, wind, or out-of-focus images

Solutions:

• Use faster shutter speeds (1/1000s or higher)
• Fly slower to reduce motion blur
• Verify camera focus settings before flight
• Fly in calmer conditions with less wind
• Check that images are sharp before processing

Inconsistent Lighting or Color Variations

Possible Causes: Changing sun position during long flights, auto-exposure variations, or mixed lighting conditions

Solutions:

• Fly during consistent lighting conditions (overcast days are ideal)
• Complete flights quickly to minimize sun angle changes
• Lock white balance settings on your camera
• Use manual exposure mode if possible

Model Reconstruction Issues

Holes or Gaps in the Model

Possible Causes: Insufficient image overlap, missing coverage areas, or reflective/featureless surfaces

Solutions:

• Re-fly the area with higher overlap settings (80-85% front and side overlap)
• Ensure complete coverage of the area with no gaps in flight path
• Add extra passes over problematic areas
• For reflective surfaces (water, glass), capture from multiple angles

Model is Distorted or Warped

Possible Causes: Insufficient viewing angles, single grid pattern limitations, or poor GPS data

Solutions:

• Use a double grid (crosshatch) pattern instead of single grid
• Combine nadir and oblique captures for better geometry
• Ensure GPS was enabled and functioning during flight
• Add more images from varied angles

Model has Incorrect Scale or Positioning

Possible Causes: Missing or inaccurate GPS data, poor GPS signal, or processing without georeference

Solutions:

• Verify GPS was enabled during flight
• Check that your drone has a strong signal before takeoff
• Manually set scale in Polycam using the Rescale tool if GPS data is unavailable

Poor Detail or Low-Resolution Mesh

Possible Causes: Flying too high, low camera resolution, or insufficient image coverage

Solutions:

• Fly at lower altitude for higher ground resolution
• Process at High or Ultra quality settings in Polycam
• Capture more images with higher overlap

Processing and Workflow Issues

Processing Fails

Possible Causes: Inconsistent images, unstable internet connection or processing quality too high for dataset

Solutions:

• Remove duplicate or unnecessary images before processing
• Delete blurry or problematic images

Artifacts or Floating Geometry

Possible Causes: Moving objects in the scene, vegetation movement, or insufficient lighting

Solutions:

• Remove images with moving objects (cars, people)
• Fly in calm conditions to minimize vegetation movement
• Avoid capturing during windy conditions