ACamViewfinder

Fast diopter planning for camera assistants. Pick the right close-up strength, check offset-aware prep estimates, and plan split framing — offline, no account

ACam Viewfinder is the camera assistant toolkit for focus pullers, 1st ACs, DPs, operators, and lens techs. Plan close-up diopters, depth of field, hyperfocal, field of view, and split framing in seconds — offline on iPhone and iPad.

Built for set and prep work: live calculations as you type or tap +/−, meters or feet, cinema format presets, and a dark cinema-kit UI you can read under stage light.

◆ QUICK DIOPTER Stop guessing close-up strength. Enter marked focus and target distance to get: • Ideal diopter power • Nearest standard glass (+⅛, +¼, +½, +1, +2, +3) • Full comparison table of resulting focus distances • BEST FIT highlight for the strength to pull from the kit

◆ PRECISION MODE Prep-grade, offset-aware diopter planning with DOF context: • Camera formats: Super 35, ARRI ALEXA 35 Open Gate, Full Frame, Large Format / VistaVision • Focal length, aperture, marked focus, target distance • Sensor-to-diopter-plane offset (mm) • Near / far depth-of-field tolerance for the setup • Load a saved lens package to fill fields instantly

◆ DIOPTER RESULT Already have glass on the lens? Enter marked focus and known diopter strength to see the resulting subject distance — perfect for kit check.

◆ VIEWFINDER & SPLIT Composition planning for camera assistants and DPs: • Horizontal and vertical field of view (FOV) • Frame width and height at subject distance • Place and rotate a split-diopter line for staging notes Planning overlay only — not an optical aberration simulator.

◆ DEPTH OF FIELD Classic near, far, and total DOF for any focus mark using the format’s circle of confusion. Built for focus pulls and stop decisions.

◆ HYPERFOCAL Set focus for near-to-infinity coverage. Get hyperfocal distance and near limit for deep-stop / landscape-style shots.

◆ SAVED LENS PACKAGES Store format, focal length, diopter-plane offset, and aperture on device. Create, edit, delete, and load packages into Precision Mode — no cloud, no account.

◆ DESIGNED FOR SET • Offline optics math — works with airplane mode • No account, no ads, no analytics SDK • First-run User Guide + Help (?) on every tool • Glove-friendly +/− steppers and live hero answers • Honest labeling: treat offset-aware results as prep estimates until verified on the glass

WHO IT’S FOR Focus pullers, 1st camera assistants, cinematographers, camera operators, rental houses, and prep technicians who work in diopters, Super 35, Full Frame, ALEXA formats, close focus, and split staging.

ACam Viewfinder answers hard focus and framing questions quickly — so you can move on with the shot.