A still image describes a moment. A reference video also describes change over time. Choose the output according to what you need to communicate and the inputs supported by your chosen generator. Reelpen prepares the reference; generation takes place in the external service.
Use video for movement and timing
Video is useful for a camera following a walking character, an approach followed by a pause, or a turn that needs a clear beginning and end. Preview the whole interval before recording. Check that the output camera sees the action, that the subject stays in frame and that the recording does not cut off the finish.
Use PNG frames for composition
Frames help explain where the subject and props belong, how large they appear and what the camera should see. Capture the start, a meaningful middle moment and the end when those arrangements matter. A set of stills does not fully specify the speed or path between them; check whether the external service supports multiple reference frames and how it interprets their order.
Keep an editable scene alongside the output
A rendered frame cannot restore your object positions or routes. Keep a native scene export when you want to revise the shot later. Use Capture or Package for the available image, video and scene outputs. Video format availability depends on the browser; inspect the downloaded file before sending it elsewhere.
Before uploading a reference
- Confirm the generator accepts your actual file format, dimensions, duration and reference type. Support can differ between models and versions.
- Watch the exported file, not only the editor preview. Check framing, start and end, movement, occlusion and floor contact.
- Describe the desired appearance, light and setting in your prompt. Explain which movement or composition the reference is intended to preserve.
- Use images and other material you have permission to upload. External services have their own access terms and charges.
Compare one change at a time
If the result misses the shot, identify whether the problem is composition, camera travel, character action or appearance. Adjust the corresponding part of the Reelpen scene and export again. Keep the previous reference and result so that you can compare attempts. No reference guarantees an exact match from an external video model.
Start with the scene-building guide, or use 3D storyboarding to plan the shot before recording.