Site Recon & Shot Planning

"Show Up and Shoot" = 40% Wasted Time

3DGS capture is not a walk-in job. Every minute on-site consumes your stable lighting window. If you arrive and only then start thinking "which direction do I walk," "which face do I shoot first," "how do I handle this glass" — you'll waste 40% of your effective time on hesitation. Light doesn't wait.

The purpose of scouting is singular: move all decisions to before capture day, so the shoot itself becomes pure execution.

Five Questions This Chapter Answers

1. What exactly should I observe and record during scouting?

2. What time of day offers the best light for my subject?

3. How do I plan a capture path that ensures coverage without backtracking?

4. If on-site conditions don't match expectations, what's Plan B?

5. What format should my shot plan take to enable zero-thinking execution?

Scouting Is Not "Having a Look" — You Must Bring Back 5 Things

Many people treat scouting like a stroll. They arrive, snap a few photos for social media, and come back remembering nothing. Effective scouting must produce these 5 pieces of information — missing any one means your shot plan is incomplete.

Light: You Have One Window — Don't Waste It

3DGS requires consistent illumination throughout the entire capture session. You cannot "shoot half in the morning, half in the afternoon" — even on the same day, if the sun angle shifts 15°, shadow directions change, and training produces two worlds stitched together.

Four Lighting Conditions Ranked by Priority

How to Determine "How Long Is My Window"

Run this experiment during scouting:

1. Stand at a fixed angle facing the subject

2. Take one photo every 15 minutes from the same position

3. Continue for 1 hour (4 photos total)

4. Compare at home — the moment shadow position and length change by more than 10% marks your window boundary

Formula:

Effective shooting time = Window duration × 0.7

Reserve 30% margin for contingencies (equipment issues, waiting for pedestrians, battery swaps).

Use Sun Surveyor to Pre-Predict Lighting

You don't need to visit the site every time to test light. Sun Surveyor (iOS/Android, $10 one-time) predicts sun trajectory and shadow direction for any location on any date:

Workflow:

1. Open Sun Surveyor → Map View

2. Pin your capture location on the map

3. Drag the time slider, observe sun azimuth and shadow length changes

4. Find the period with shortest/most stable shadows → this is your shooting window

5. Switch to AR View → overlay sun trajectory on your phone camera in real-time

Free alternatives: Sun Seeker (iOS $10), PhotoTime (free, fewer features), SolarApp (free, shadow simulation)

Path Planning: Coverage vs Efficiency

The core tension in capture path planning: you need to cover all angles, but cannot backtrack (backtracking = light has changed = inconsistency between earlier and later shots).

Scene Paths: One-Way Loop

Principle: Start at the entrance, walk along walls in one direction, form a closed loop. No backtracking.

Critical at corners: Corners are where SfM is most likely to break. Start increasing density 1m before the corner, continue 1m after. Each corner needs ≥8 photos to ensure ≥30% co-visibility between the two corridor segments.

Object Paths: Three-Ring Orbit

Principle: Object stays still, you orbit it three times (top/middle/bottom), each ring at a different height.

Continuity between rings: When transitioning from Ring 1 to Ring 2, don't suddenly jump to the new height. Over 5-6 transitional shots, gradually raise the camera to maintain ≥80% frame overlap between adjacent shots. Sudden jumps = SfM chain break.

Building Exterior Paths: Ground Loop + Drone Top Fill

Principle: Ground-level orbit for facades, drone fills rooftop and 45° oblique angles.

Plan B When On-Site Conditions Don't Match

Scouting showed perfect conditions, but capture day might bring weather changes, construction, or crowds. Prepare Plan B in advance:

Shot Plan Template: One Page, Zero-Thinking Execution

The shot plan must fit on one page. Print it on capture day, bring it to the site, follow it step by step.

Template Format

# Timing arrive: "08:30" start_shooting: "09:00" hard_stop: "11:30"
# Window boundary window_hours: 2.5 effective_time: "2.5 × 0.7 = 1.75 hours"
# Equipment camera: "Sony A7M4 + FE 24mm f/1.4 GM" backup_lens: "FE 35mm f/1.8" accessories:
- CPL polarizing filter (for display case glass)
- Tripod (for dark corner fill shots)
- SD card 128GB × 2
- Batteries × 3 (each ~500 shots)
- LED panel light × 1 (backup fill)
# Path start_point: "Main entrance, left side" direction: "Counter-clockwise" estimated_shots: 180 key_nodes:
- "Entry hall: 20 shots (include ceiling looking up)"
- "Gallery A: 40 shots (watch display case glass, CPL on)"
- "Corridor transition: 15 shots (increase density, ensure connection)"
- "Gallery B: 50 shots (large sculpture: separate orbit 30 shots)"
- "Back hall: 30 shots"
- "Return to entrance: 15 shots (loop closure overlap)"
# Floor Plan # [Attach hand-drawn floor plan photo]
# Plan B rain: "Indoor — unaffected, continue" crowd: "Wait for 30-second gaps, or fill shots after 11:30 when fewer people" light_change: "Close all curtains, switch to pure artificial light mode"
# Exit Checklist checklist:
- "□ All wall surfaces covered"
- "□ Ceiling/floor ≥10 shots each"
- "□ Display case glass areas shot with CPL"
- "□ Corner transitions density increased"
- "□ SD card backed up to phone/laptop"
- "□ Total count ≥ 80% of estimate"

Polycam / Scaniverse Quick Scouting Technique

If you're using a phone cloud workflow (Polycam / Scaniverse), scouting can be lighter:

1. On arrival, do a quick scan with Scaniverse (Gaussian Splat mode, 60-second scan → 5-minute processing)

2. Review the result: Where are the holes? Where are the floaters? Where is it blurry?

3. These problem areas are exactly where you need increased density during the real capture

4. Annotate problem areas on your floor plan → scouting complete

The benefit: in 10 minutes you get a "preview version" showing exactly where problems will occur. Targeted density during the real capture is 3× more efficient than blind shooting.

Next Steps

• Scouting complete, ready for capture → Enter 03-Camera Parameters & Field Operations

• Want to review subject classification first → Back to 01-Subject Classification & Capture Strategy

• Going straight to cloud workflow → Enter 08-Training