Max AI video length: Runway Gen-4.5 10 s vs Sume's 30-second rows

Runway's changelog lists Gen-4.5 at 2 to 10 seconds and Gemini Omni Flash at 3 to 10 seconds (Runway changelog, read 2026-10-09). Sume's docs give wan-3.0 2 to 30 seconds and seedance-2.5 4 to 30 seconds, while its Omni row stays at 3 to 10. For a one-take clip over 10 seconds you need a model with a longer ceiling.

What is the longest clip per model?

Sume lengths are from the video generation docs. They also say each other catalog model has a maximum of 15 seconds, and GET /v1/videos/models reports the live supported_durations.

What does a long clip cost?

Length is not free. Omni on Sume is $0.125 a second at 720p, so 10 seconds is $1.25. Wan 3.0 and Seedance 2.5 have their own rates, so read the price for your resolution in the docs before you submit; Sume reserves the provider list times 1.25 per output second at submit.

When should you stitch instead?

Sume joins clips on its timeline; the docs treat the clip sequence and audio as Timeline 1.0 work.

• You need cuts: three 10-second Omni clips with different shots read better than one long take.
• You need 4K: Omni lists 4K and stops at 10 seconds, so build a longer 4K sequence from 10-second clips.
• You need to repair a middle section: re-render one clip, not the whole minute.