Need a 7-second ad? Kandinsky's fixed 5 s vs Sume exact seconds

A 7-second ad does not fit a model that only makes 5-second clips, and the Kandinsky Lab page (read 2026-10-11) describes 5-second clips. On Sume, Gemini Omni Flash 1.1 and Wan 3.0 both accept 7 seconds in one job, so you pay for exactly 7 seconds: $0.2625 on Omni at 360p, $0.875 at 720p.

There is a second route: render two shorter clips and join them on a Timeline render. It buys you a cut at the price of a $0.10 render line, so ask for the exact length first.

What each Sume row allows for a 7-second ask

The accepted lengths come from the Sume video docs and the model rows in the repository. Omni accepts 3 to 10 seconds, so 7 is inside the range. Wan 3.0 accepts 2 to 30 seconds. MiniMax H3 Max accepts 5 to 15 seconds. A row with a minimum above 7 seconds would force you to over-buy and trim.

Rates below are the Sume price per second: the list price times the 1.25 house margin, taken from the price tables and golden tests.

The join route: 4 seconds plus 3 seconds

Suppose you want a hard cut halfway through. Omni's minimum is 3 seconds, so a 4-second clip and a 3-second clip add up to 7. At 360p that is $0.15 plus $0.1125, which is $0.2625: the same footage cost as the single job. The Timeline render then adds $0.10, because Sume bills $0.10 per output minute rounded up and a 7-second output rounds to one minute. The joined version costs $0.3625.

The same maths shows why a 5-second-only model is awkward for this length. Two 5-second clips give 10 seconds, and you pay for 10 seconds of footage to use 7. At Omni 360p two 5-second clips cost $0.375, plus $0.10 for the render, against $0.2625 for a single 7-second job.

When trimming is cheaper than regenerating

If a 5-second clip is already good and you need only 2 more seconds of screen time, the cheapest fix is often a Timeline render that holds or loops it, not a new generation. Timeline reports soft warnings when it pads or loops short sources, and those are not failures. Check the result for judder before you publish; a loop on a moving subject can look like a stutter.

Sume's Timeline docs list the program fields, including video[].duration with a minimum of 0.2 seconds, and the fit modes for matching a vertical frame.

Checking the cost before you submit

Sume's docs say the job reserve and the final bill follow the same rate, so you can compute a length by hand before you call the API. Multiply the seconds by the per-second figure in the table, then check the live rate in GET /v1/catalog, which the Timeline docs name as the place to confirm rates.

If you also want a voice line over the 7 seconds, remember that audio jobs, composes and captions have their own small per-job prices in the Sume price tables. Add them after the footage so the total stays explainable line by line. A buyer who sees $0.2625 for footage plus $0.10 for the render can reconcile each line with the usage summary later.

A short rule for lengths

Ask for the length you need when a row allows it. Use a join only when you want two different shots. Use the shortest-clip table to see each row's floor, and the 30-second ad breakdown when the plan grows to several shots.

Kandinsky is not a Sume row, so none of the figures above are Kandinsky prices. They are what the same length costs on rows you can call today.