Episode four of the single-shot ladder, and the least glamorous, most money-saving one. Four settings, decided *in order, before you generate*, stop you discovering constraints the expensive way. **Aspect ratio** is a generation setting, not a crop you fix later. We cover 16:9 (landscape/YouTube), 9:16 (vertical/TikTok, Reels, Shorts), 1:1, 4:3, and cinemascope; why cropping a horizontal hero shot to vertical throws away ~40%+ of the frame, the context, and the resolution; the [adapt-across-ratios trick](https://chierhu.medium.com/adapting-videos-for-horizontal-vertical-and-other-aspect-ratios-563837a47fd0) of framing for the tightest crop first; and the [vertical safe zone](https://edicionvideopro.com/en/editing-techniques/916-aspect-ratio-guide-vertical-video-for-tiktok-reels/) where platform UI eats your frame. **Duration** has a low wall (most clips land ~4–10s, a few push to 15s) because of [temporal drift](https://imerit.ai/resources/blog/solving-temporal-drift-in-ai-generated-video/), the loss of coherence past ~5–8 seconds. The fix isn't chasing the longest single clip; it's planning short shots and chaining them (full episode next). We also separate honest chaining from auto-extend. **Resolution** is draft-cheap, finish-sharp: iterate at 720p, render the winner at delivery res, which can [cut iteration cost by ~60%](https://wavespeed.ai/blog/posts/ltx-2-3-portrait-video-9-16-workflow-2026/), and reach 4K with an upscaler (Topaz) rather than generating 4K drafts. **FPS** sets motion feel (24 filmic / 30 broadcast / 60 smooth), is changeable after the fact via frame interpolation, and must stay constant across a chain. Plus the pre-flight checklist (destination → ratio → duration plan → draft res → final res/fps → upscale), credit-math worked examples, a universal vertical export spec, and the pitfall: the gorgeous 16:9 shot the client wanted vertical. Callbacks to ep1 (bench the leaderboard at *your* ratio/duration/res), ep2 (bake constraints into the prompt), ep3 (start frames). Forward to keyframe chaining and finishing. *AI-generated podcast by OCDevel. Caps, tiers, and prices move monthly; verify on the live leaderboard and bench your own shot.*