What Is Multispectral Imaging?
Regular cameras capture 3 channels (Red, Green, Blue). Multispectral cameras capture 4-10+ specific bands across the electromagnetic spectrum, including invisible wavelengths like near-infrared (NIR) and red edge. It's like going from tasting only sweet-sour-salty to also sensing umami and texture â you get a much richer understanding of what you're looking at.
Multispectral vs Hyperspectral
The key difference is the number and width of spectral bands:
| Feature | Multispectral | Hyperspectral |
|---|---|---|
| Bands | 4-10 | 100-300 |
| Bandwidth | 10-50nm | 5-10nm |
| Data size | 10-100MB | 1-10GB |
| Cost | 50K | 200K+ |
| Processing | Simple | Complex |
| Use case | Agriculture, basic analysis | Mineralogy, detailed research |
Python: Computing Vegetation Indices
Hands-On Project: Crop Health Map Generator
Key Takeaways
- Multispectral cameras capture 4-10+ narrow spectral bands beyond visible light
- NDVI = (NIR â Red) / (NIR + Red) â the most common vegetation health index
- Red Edge band (717nm) is crucial for detecting early plant stress
- Hyperspectral captures 100+ continuous bands for detailed material analysis
- Applications: precision agriculture, environmental monitoring, mineral exploration
- Band combination determines which indices can be computed