Prompt de physique de la photographie macro

2x2 grid, 16:9, ai picks different subjects: INPUT = [ SUBJECT / MAGNIFICATION m / APERTURE N / METHOD / T ] UNKNOWNS m · N · k (stack count) · working distance w LAWS bellows N_eff = N·(1+m). At 1:1, f/16 diffracts like f/32. ⇒ high m + small aperture CANNOT be crisp. Softness is mandatory. DOF total DOF ≈ 2Nc(1+m)/m². At 1:1, f/8, this is ≈0.5mm. ⇒ a beetle sharp head to abdomen is EVIDENCE OF A STACK, k>1. stacking a stack leaves signatures: halo at high-contrast edges, ghosted hairs, background-to-foreground transition artifacts, and a MAGNIFICATION RAMP across slices unless telecentric. It also requires a MOTIONLESS subject ⇒ pinned, chilled, or dead. light at w = 5cm, a 20cm softbox subtends ~64° ⇒ shadows are soft and wraparound. Specular highlight size = source angular size. Small flash at macro distance is still relatively large. bokeh background blur circle ∝ m² ⇒ at high m the background is obliterated to smooth wash, with no recoverable structure. OVERDETERMINATION 4 unknowns, 7 routes ⇒ 3 redundancies m̂_DOF_slab m̂_diffraction_softness m̂_background_obliteration N̂_specular_size N̂_diffraction ŵ_perspective_compression k̂_edge_halos NESTED EXPOSURE T with flash ≈ 1/10000s duration. Frozen wing ⇒ frozen dust. HONEST one m explains DOF depth, diffraction, and background wash together FORBIDDEN insect sharp front-to-back, zero stack artifacts → DOF 1:1 at f/22 rendered tack sharp → diffraction live subject stacked with limbs in one position → stacking requires stillness hard tiny specular from a large near source → angular size structured recognisable background at 2:1 → bokeh scaling