Mapping Drone Cameras

DJI and other mapping drone manufacturers have been tweaking and adjusting their cameras for the last decade. Sometimes, with giant steps forward, and other times, the moves are a head-scratcher. The purpose of this blog is to summarize DJI’s most recent cameras. DJI has been a leader in the drone industry, and their camera technology has evolved significantly over the years.

Camera Parts

The following diagram how the basic parts of a camera.

Sensor size

The sensor size of a camera is a critical factor influencing the quality of images and videos produced. It refers to the physical dimensions of the image sensor inside the camera, which captures light and converts it into an electronic signal. Here’s an overview of how sensor size affects camera performance:

Impact of Sensor Size:

1. Image Quality:
   • Larger Sensors: Generally capture more light, which leads to better image quality, especially in low-light conditions. They provide greater detail, better dynamic range, and reduced noise in images.
   • Smaller Sensors: May struggle with noise and detail retention in low-light conditions, producing images with less clarity and more grain.
2. Depth of Field:
   • Larger Sensors: Offer a shallower depth of field, allowing for more pronounced background blur (bokeh). This effect can be useful for isolating subjects and achieving a professional look.
   • Smaller Sensors: Typically have a deeper depth of field, making it harder to achieve the same level of background blur. This can be advantageous for capturing more of the scene in focus, but may not provide the same aesthetic effect.
3. Field of View:
   • Larger Sensors: Generally provide a wider field of view compared to smaller sensors when using lenses with the same focal length. This can be beneficial for capturing more expansive scenes.
   • Smaller Sensors: May have a narrower field of view, which can be a limitation if wide-angle shots are desired.
4. Lens Compatibility:
   • Larger Sensors: Often require lenses with higher quality to fully utilize their capabilities. The investment in high-quality lenses can be significant.
   • Smaller Sensors: Can use a wider range of lenses, including more affordable options, while still achieving good image quality.

Common Sensor Sizes:

1. Full-Frame (35.9 x 24.0 mm):
   • Equivalent to a 35mm film frame.
   • Provides high image quality, excellent low-light performance, and a shallow depth of field.
2. APS-C (Approximately 22.5 x 15.0 mm):
   • Common in many consumer and mid-range DSLRs and mirrorless cameras.
   • Offers a good balance between image quality and camera size, with a crop factor of about 1.5x compared to full-frame sensors.
3. Micro Four Thirds (17.3 x 13.0 mm):
   • Used in many mirrorless cameras.
   • Provides a smaller form factor and a crop factor of 2x, making lenses appear longer than on full-frame cameras.
4. 1-inch (13.2 x 8.8 mm):
   • Often found in high-end compact cameras and some drones.
   • Balances image quality and portability, with a crop factor of about 2.7x.
5. 1/2.3-inch (6.17 x 4.55 mm):
   • Common in many consumer-grade compact cameras and some drones.
   • Provides adequate image quality for basic needs but may struggle with low-light performance.

Resolution

Camera resolution refers to the amount of detail an image can capture, typically measured in pixels. Higher resolution generally means more detail and clarity, but the practical benefits depend on several factors beyond just pixel count. Here’s a breakdown of camera resolution and its implications:

Resolution Basics:

Pixels: Pixels are the smallest units of an image. Resolution is often expressed as the total number of pixels in an image, such as 8 megapixels (MP), where one megapixel equals one million pixels.

Megapixels: One megapixel is one million pixels. Common resolutions are described in megapixels, e.g., a 12 MP camera has a resolution of 4000 x 3000 pixels.

Impact: Higher megapixel counts can capture more detail, but image quality also depends on sensor size, lens quality, and processing.

Focal Length / Field of View

Focal length: The distance between the lens and the image sensor when the subject is in focus. It’s usually measured in millimeters (mm).

A shorter focal length (wide-angle lens) results in a wider field of view, capturing more of the scene in a single frame. Conversely, a longer focal length (telephoto lens) narrows the field of view but allows for more detailed zoomed-in images.

The field of view can be calculated using the focal length and sensor size, which is crucial for determining how much area you can cover in each image:

• Horizontal FOV: Uses the width of the sensor.
• Vertical FOV: Uses the height of the sensor.

Drone Cameras different types of shutters

Drone cameras utilize different types of shutters to control the exposure of images. Here are the main types:

Global Shutter: Captures the entire frame at once, freezing motion and preventing rolling artifacts.

• Advantages: Ideal for high-speed photography and fast-moving subjects; no distortion from camera movement.

Rolling Shutter: Captures the image line by line from top to bottom, which can cause distortion in fast-moving scenes.

• Advantages: More common and cost-effective; consumes less power.
• Disadvantages: Can produce “rolling” distortion or artifacts, especially with fast-moving objects or during rapid camera movement.

Mechanical Shutter: A physical shutter that opens and closes to expose the sensor to light.

• Advantages: Reduces motion blur and rolling shutter effects. Better for high-speed photography.
• Use Cases: Sports, fast-moving subjects, and high-contrast scenes.

Electronic Shutter: The sensor is exposed electronically without a physical mechanism.

• Advantages: No moving parts, reducing weight and complexity, faster shutter speeds, allowing for burst shooting.
• Use Cases: Aerial photography in varied light conditions, landscapes, and slower-moving subjects.

Read more about some of the best drones (affordable and high end) out there with specific camera and shutters types