a7R III — Format, Aperture & Prime Settings

Full-frame vs APS-C mode

On the a7R III, APS-C/Super35 applies a 1.5× crop: a 24mm reads ~36mm, a 35mm reads ~52.5mm. Aperture is unchanged, but for the same framing the depth of field is effectively deeper, and resolution drops (24mm → ~16 MP; 35mm → ~18 MP). Full frame keeps the true wide field and full 42 MP; APS-C gives reach and a more natural perspective.

• Landscape / cityscape → full frame: true 24mm, max resolution, wide-angle drama. f/8–f/11, tripod when possible.
• Environmental street → APS-C: 24mm becomes a natural ~36mm — the classic street "sweet spot" — discreet and subject-forward. Assign APS-C/Super35 to C1/C2 to flip instantly, so one 24mm covers both.

24mm GM zone-focus street setup (APS-C)

APS-C · f/8 · Manual Focus · focus 3 m · Auto ISO 100–3200 · 1/250 s.

• Aperture Priority (A); f/8 bright, f/5.6 overcast, f/4 late/cloud.
• Manual Focus set to ~3 m — at 36mm equiv, f/8 holds roughly 1.5 m→∞.
• Auto ISO with a 1/250 s minimum (1/500 s for brisk movers).
• Turn Peaking and magnification off; rely on distance + depth of field. Drive: Single/Low; Metering: Multi.
• Low light: open to f/4, raise Auto ISO ceiling to 6400, pull the zone to ~2.5–4 m.

Optimal apertures — FE 24mm F1.4 GM

Purpose	Aperture
Astrophotography / night sky	f/1.4–f/2 (Milky Way f/1.4; star fields f/1.8–f/2)
Environmental portrait / street	f/1.4–f/2.8
Landscape (peak sharpness)	f/4–f/5.6
Architecture / hyperfocal	f/5.6
Maximum depth of field	f/8 (f/11 acceptable)
Avoid	f/16–f/22 (diffraction; f/22 only for starbursts)

a7R III + 40mm prime — general settings

Aperture Priority (A); f/2.5–f/4 (wide for low light and separation); Auto ISO capped 3200–6400; let the camera pick shutter (min 1/125 s for movers); Metering Multi (Spot for faces/highlights); Continuous AF (AF-C); Drive low-speed continuous; White Balance Cloudy or Auto for a touch of warmth on grey days.

Consolidated from notes: Using 24mm in asp-c mode; full-frame mode and APS-C mode; optimal aperture guide for the Sony FE 24mm f-1.4 GM; 2 Jul 2025 (40mm prime settings)