# Validation Log

## Validation Scenario
A balloon at 10km altitude in eastern Ukraine on a sunny day needs to photograph a convoy of military trucks on a road. The AI model (trained on 600-1000m imagery at 10-20 cm/pixel) must detect and classify the vehicles.

## Expected Based on Conclusions

### Using ViewPro Z40K:
- GSD at max zoom: 10.3 cm/pixel. Each truck (~8m long) ≈ 78 pixels long in the image.
- FOV: 606×453m — covers a road segment of ~600m. Can see multiple vehicles.
- Image quality: 25.9MP provides good detail. Small sensor (1/2.3") may show some contrast loss from haze in sunny conditions.
- Integration: Serial control from companion computer. Can trigger photos and adjust zoom remotely.
- Expected: Model should detect trucks with reasonable confidence. May need dehazing in hazy conditions.

### Using A40TR Pro:
- GSD at max zoom: 11.6 cm/pixel. Each truck ≈ 69 pixels long.
- FOV: 297×223m — narrower coverage, fewer vehicles per frame.
- Thermal camera adds night capability and can detect engine heat signatures.
- MIL-STD certified, most robust for field conditions.
- Expected: Model should detect trucks. Thermal overlay provides backup detection.

### Using Sony α7RV + 400-800mm:
- At 600mm (15.8 cm GSD target): GSD = 6.3 cm/pixel. Each truck ≈ 127 pixels long.
- FOV: 599×399m — good coverage.
- Full-frame sensor captures more light per pixel, better contrast through haze.
- Expected: Best image quality. Model may need GSD adjustment (zoom to match 10-20cm range or downscale).
- Risk: Gimbal at weight limit may cause jitter on balloon. Integration is complex.

## Actual Validation Results (analytical)

1. All three systems can achieve the target 10-20 cm/pixel GSD — validated by calculation
2. Trucks at 10-20 cm/pixel occupy ~40-80 pixels in length — sufficient for CNN-based detection models
3. Atmospheric haze in sunny conditions over Ukraine plains is typically moderate — dehazing should be effective
4. Balloon passive stabilization is the unvalidated risk — needs physical prototyping

## Counterexamples

1. **Cloudy/hazy day**: Small-sensor cameras will produce significantly degraded imagery. The Sony full-frame option is more resilient but still affected. Cloud cover completely blocks all optical imaging.
2. **Nighttime**: Only A40TR Pro and SIYI ZT30 have thermal cameras for night operation. Others are daylight-only.
3. **Fast-moving targets**: At 10km range, even fast vehicles appear slow relative to the camera. Not a concern.
4. **Very small targets**: People or small objects at 10-20 cm/pixel would be only a few pixels — below detection threshold. This use case is for trucks/vehicles only.

## Review Checklist
- [x] Draft conclusions consistent with fact cards
- [x] No important dimensions missed
- [x] No over-extrapolation
- [x] Conclusions actionable — user can purchase any recommended system
- [ ] Note: Balloon-specific stabilization requires physical validation

## Conclusions Requiring Revision
None — but balloon motion compensation is flagged as the key unknown requiring prototyping.
