1. What is the Pixel Scale Calculator?

The Pixel Scale Calculator determines the angular size of each pixel in an astrophotography setup, measured in arcseconds per pixel. This is crucial for matching your camera and telescope combination to achieve optimal sampling for your astronomical imaging.

2. How Does the Calculator Work?

The calculator uses the pixel scale formula:

Where:

• \( Sensor Size \) — Physical size of the camera sensor in millimeters
• \( Resolution \) — Number of pixels along the measured dimension
• \( Focal Length \) — Focal length of the telescope or lens in millimeters
• \( 206265 \) — Conversion factor (arcseconds per radian)

Explanation: The formula calculates how many arcseconds of sky are covered by each individual pixel in your camera sensor.

3. Importance of Pixel Scale Calculation

Details: Proper pixel scale is essential for achieving optimal image resolution in astrophotography. It helps determine if your setup is undersampled (missing detail) or oversampled (wasting resolution) for your specific imaging goals and seeing conditions.

4. Using the Calculator

Tips: Enter the sensor size in millimeters, resolution in pixels, and focal length in millimeters. All values must be positive numbers. For rectangular sensors, calculate separately for both dimensions if needed.

5. Frequently Asked Questions (FAQ)

Q1: What is the ideal pixel scale for astrophotography?
A: The ideal pixel scale depends on your seeing conditions and telescope. Generally, 1-3 arcseconds per pixel works well for deep-sky objects, while planetary imaging benefits from smaller scales (0.1-0.5 arcseconds per pixel).

Q2: How does pixel scale affect image quality?
A: Proper sampling (2-3 pixels per seeing disk) captures maximum detail without wasting resolution. Undersampling misses detail, while oversampling doesn't improve resolution and may increase noise.

Q3: Should I use horizontal or vertical resolution?
A: For square pixels, either dimension works. For non-square pixels, calculate both dimensions separately. Most modern cameras have square pixels.

Q4: Can I use this calculator for binoculars or spotting scopes?
A: Yes, the formula works for any optical system. Just use the appropriate focal length and your camera's sensor specifications.

Q5: How does binning affect pixel scale?
A: Binning combines adjacent pixels, effectively increasing the pixel size and changing the pixel scale accordingly. 2x2 binning doubles the pixel scale.