Correct the shutter before you pull.

Reciprocity, ND stacks, bellows, and format-aware DOF. Offline. Pocketable. Shareable.

16emulsions

13filters

14field setups

4formats

01 — Intent

Charts used to live in a binder.

ND plus polarizer is already several stops. A 210 mm rail on a 150 mm lens is about +1. Velvia past one second is not linear. The bench totals EI, stacked filters, and bellows, then optionally rewrites the shutter from the stock p-curve. Workshop values — confirm with a test strip when the sheet cannot be reshot.

02 — Studio

Live triangle on a factor stage

Home lists setups, filterable by 35mm / 120 / 4×5 / 8×10. Bench: tiles snap to a 16 px grid, undo/redo, save, share. Shutter 1/1000–2 min, apertures full or thirds f/1.4–f/64, EI 25–3200. Output: each stop group, pre-reciprocity time, final shutter. Plain-text card or 1080×640 still. Home widget keeps the last headline.

03 — Stocks

Sixteen curves, favorites already starred

B&W

HP5 1.31 · Tri-X 1.33 · T-Max 400/100 · Delta 100/400 · FP4 · Pan F · Acros II 1.08 after 2 s · XP2

Color neg

Portra 400 / 160 · Ektar 100 · Cinestill 800T (rate 500 under mixed LED)

Slide

Velvia 50 p≈1.60 — hungry after dusk. Provia 100F still stretches past two seconds.

04 — Lab

Four tools. No arithmetic in the spray.

Filter stacker

ND 0.3–3.0, linear / CPL, 85B, 80A, Wratten 8 / 21 / 25 / 11. Density adds. A 1/125 sample rewrites live.

Reciprocity + rails

t × (t / threshold)^(p−1). Bellows: 2 × log2(extension / focal) only if the rail is longer than the lens.

DOF

CoC 0.029 / 0.045 / 0.10 / 0.20 mm. Near, far, infinity. 35mm f/8 is not 4×5 f/8.

05 — Chain

EI + filters + bellows, then the curve

EI stops = log2(box / working). Filters sum. Bellows if extension > focal. Shutter × 2^stops, then the p-curve if reciprocity is on. Toggle it off to isolate the stretch. Daily insights rotate locally. Theme, default format, full vs ⅓ stops. Room + DataStore — no cloud meter.

01Night City Neon — HP5 · 1 s · 35mm

02Waterfall Veil — FP4 · ND 1.8 · 120

03Studio Bellows — Portra 160 · 210/150 · 4×5

04Redwood Canopy — Delta 100 · green 11

05Still Life — Ektar · 8×10 · pola

06Polarized Facade — Velvia · CPL

07Cascade Macro — Acros · 280 mm rail

08Market Steam — 800T @ 500

06 — Support

Kukulenko_Developer

Wrong time, missing stock, failed share, DOF vs ground glass: maureenperez482@gmail.com. Send stock, both EIs, metered shutter, aperture, stack, bellows/focal, both times. Replies in order, a few business days. Not a lab.

Frequently asked questions

Does it work without a signal?

Yes. Share is the only exit, and only if you tap it.

Why is the corrected time so long?

EI + filters + bellows, then the p-curve past threshold. Velvia is hungry; Acros is calm.

Are p-curves a warranty?

No. Typical values. Bracket the sheet you cannot repeat.

How do I stack filters?

Bench tiles add stops. Lab stacker taps ND / pola / CC / contrast.

Why is 4×5 shallower at the same f-stop?

Circle of confusion scales with format. Use the DOF card.

What does a different EI do?

Stop math only — not a development recipe.

Who do I write?

maureenperez482@gmail.com with the full chain. Rail equal to focal adds zero.