Master the Science of Filmmaking
Guides to the mathematics, formulas and technical knowledge that filmmakers use every day, from aspect ratios and frame rates to storage, delivery specs and DCPs.
Camera and lens
Depth of field, field of view, matching lenses across sensors, exposure and anamorphic squeeze.
- Depth of FieldNear and far limits, what changes them, sensor size and Super 35 charts in feet and meters.Depth of Field
- Hyperfocal DistanceHyperfocal charts for five formats in feet and meters, the formula and when to use it.Depth of Field
- Circle of ConfusionWhat the circle of confusion is, values by format, and when to choose a tighter one.Depth of Field
- Split FocusThe focus point and stop that hold two subjects sharp, with charts and set alternatives.Depth of Field
- Close Focus, Diopters & Extension TubesMinimum focus distance, diopter focus ranges, extension tube magnification and light loss.Close Focus
- Field of View Calculator GuideAngle of view by format, frame size at a distance, and the lens or distance for the frame you want.Field of View
- Crop Factor & Focal Length EquivalenceMatching a shot across sensors: width vs diagonal crop factors, equivalent lenses and equivalent aperture.Focal Length Match
- Cinema Camera Sensor Size ChartActive sensor area per recording mode for current cinema cameras, from the makers' own spec pages.Field of View
- Open Gate vs 16:9 vs AnamorphicHow recording modes and anamorphic squeeze change the horizontal and vertical field of view.Field of View
- Exposure Triangle for CinemaT-stop, shutter angle, EI and ND in stops, what each one costs, and the order a camera team sets them.Exposure
- Shutter Angle vs Shutter SpeedAngle-to-speed charts for every common frame rate, and the flicker-free angles on 50 Hz and 60 Hz power.Exposure
- ND Filter ChartDensity, stops and filter factor for every common ND, ND from a meter reading, stacking and IR.Exposure
- Exposure Value (EV) ChartEV charts for stills and cinema settings, the ISO offset, and a meter EV reading turned into a T-stop and ND.Exposure
- Anamorphic DesqueezeWhat each squeeze gives on each sensor shape, anamorphic sensor modes, desqueezing in post and 2.39:1 delivery sizes.Anamorphic
- Anamorphic vs SphericalScope from anamorphic glass or a spherical 2.39 crop: sensor used, matching focal lengths, look and trade-offs.Anamorphic
Post-production
Frame rates, timecode, codecs, proxies, pulldown and audio sample rates for editors and post teams.
- Frame Rates ExplainedWhere 23.976 and 29.97 came from, what 24, 25, 50 and 59.94 are for, and how to choose.Speed Change
- Drop-Frame TimecodeWhich frame numbers drop-frame skips, 17,982 frames per 10 minutes, and DF vs NDF in practice.Timecode Calculator
- Timecode on SetLTC and VITC, jam sync, free run vs record run, sync boxes and drift, and syncing sound in post.Timecode Calculator
- Codecs for EditingProRes, DNxHR and H.264/HEVC compared: intraframe vs long-GOP, chroma, bit depth and GB per hour.Data & Storage
- Proxy WorkflowsProxy codecs and sizes, storage per hour, and relinking in Premiere Pro, Resolve, Final Cut Pro and Avid.Data & Storage
- 3:2 Pulldown & Frame Rate Conversion3:2 pulldown, the 24 → 25 fps speed-up, and converting between frame rates without breaking sync.Speed Change
- Audio Sample Rates & Sync48 kHz, samples per frame, 48.048 kHz and pull-down, and keeping sound in sync.Speed Change
Reference guides
The long formula guides: lenses and exposure, production math, and encoding and delivery.
- Cinema Calculations HandbookDepth of field, hyperfocal distance, angle of view, crop factors, exposure, ND and gel mireds.Depth of Field
- Filmmaking MathLetterbox bars, frame rates, drop-frame timecode, film footage, storage and transfer sums.Timecode Calculator
- Video Production FormulasCompression ratios, file sizes, streaming bitrates, scaling and audio loudness.Data & Storage
Calculations
Bitrate, storage, RAID and LTO tape, camera cards, time-lapse, slow motion and color, worked through step by step.
- How to Calculate BitrateBitrate from file size and duration, and the streaming bitrates platforms ask for.Data & Storage
- Color Gamut & Grading CalculationsGamut coverage from the primaries, HDR-to-SDR reference levels, mired shifts, bit depth and LUT sizes.
- Slow Motion CalculationsSlow-motion factor, speed, running time, speed ramps and shutter from capture and timeline frame rates.Speed Change
- Video Storage PlanningGigabytes per hour by codec, footage from shooting ratio, backups, RAID capacity and transfer times.Data & Storage
- RAID Capacity and Rebuild RiskUsable capacity by RAID level, drives for a target size, rebuild time and URE risk.Storage/RAID
- TB vs TiBDecimal vs binary units, drive sizes in TiB, and keeping footage plans in one system.Data & Storage
- LTO Tape ArchivingLTO-7 to LTO-10 capacity and speed, tape counts, write time, LTFS and checksums.Data & Storage
- Camera Card SpeedsVPG and Video Speed Class, bitrate to card class, record time and offload time.Data & Storage
- Time-Lapse CalculationsInterval, frame count and speed-up, exposure limits and storage for a time-lapse.Time Lapse
- Hyperlapse and Day-to-NightStep length and crop margin for a hyperlapse, twilight timing and exposure ramps.Time Lapse
Formats
What 4K, HDR and DCP deliverables involve, and the numbers behind them.
- 4K ProductionUHD and DCI 4K, ProRes and raw data rates, storage per hour and transfer time.Data & Storage
- What Is a DCP?What a Digital Cinema Package contains, how big one is, SMPTE vs Interop and KDMs.Data & Storage
- HDR VideoPQ code values to nits, HLG, reference white, HDR metadata and HDR delivery.Data & Storage
Platforms
Upload specs, sizes and bitrates for YouTube, TikTok and Instagram.
- Instagram Video SpecsReels, Stories and feed sizes, lengths, covers, safe zones and file sizes.Aspect Ratio
- TikTok Video SpecsStudio, API and ad limits for length, file size and resolution, plus file-size and upload-time math.Aspect Ratio
- YouTube Video SpecsRecommended upload bitrates for SDR and HDR, Live encoder settings, Shorts, thumbnails, storage and upload time.Data & Storage
Workflows
Delivery specs for Netflix, Apple TV and Prime Video, broadcast, festivals and aggregators: IMF, loudness, captions and deliverables.
- Aggregator Delivery WorkflowWho is operating, Filmhub's spec, captions, artwork, QC, and master size and upload time.Upload Time
- Film Festival DeliveryScreener and DCP specs from Sundance, Berlinale, Cannes and Venice, with size and upload math.Data & Storage
- Netflix Delivery SpecsApproved cameras, the App 2E IMF, Dolby Vision, the −27 LKFS mix and timed text rules.Data & Storage
- IMF Packages ExplainedAsset Map, PKL, CPL and track files, supplemental packages and the App 2E limits.Data & Storage
- Loudness Standards by PlatformEvery published loudness target, how it is measured and its true-peak limit.
- Caption & Subtitle FormatsSRT, WebVTT, SCC, TTML and IMSC; SDH vs CC; platform formats and reading speeds.Timecode Calculator
- Apple TV & Prime Video DeliveryProRes masters, HDR, audio, captions and artwork from Apple's and Amazon's public specs.Data & Storage
- Broadcast Deliverables ChecklistTextless, M&E, stems, captions, PSE testing and QC, with UK DPP and PBS layouts.Timecode Calculator
- Distribution DeliverablesA delivery schedule item by item: masters, sound, text, legal paperwork and publicity.Data & Storage