Photo Setup Calculator — Model Photography Guide

Calculates camera working distance, backdrop (sweep) dimensions, key-light distance and tripod height from your model size and camera setup. Defaults follow standard product-photography practice: a backdrop 2–3× the subject size, a key light at 45° and the camera near the model's mid-line.

Formula

• Effective focal length = Lens mm × Crop factor (full frame 1×, APS-C 1.5×, Micro Four Thirds 2×)
• Camera distance = (Effective focal × Model length) ÷ (36 mm × Camera distance ratio) — using the full-frame width 36 mm with the crop-corrected focal is the same as using the real sensor width with the real focal length
• Backdrop width = Model length × Backdrop width multiplier (default 2.5× — keeps the edges outside the frame)
• Backdrop height = Model height × 3 + Model length × Backdrop height ratio
• Key light distance = Model length × Light distance multiplier (default 1.5×, positioned at 45°)
• Tripod height = Model height × Tripod height multiplier (default 1.5×, shooting near the mid-line)

The recommended f-stop (f/5.6 to f/16) is a quick convenience heuristic keyed on model size — larger models are stopped down for front-to-back sharpness, very small models open up because depth of field is already shallow at close working distances. Confirm against your camera's depth-of-field preview.