Focus Hints

When you render a video in a different aspect ratio than the original, parts of the frame get cropped. Focus hints tell StarZero Agents exactly what to keep centered and visible during that crop.

Why Focus Hints Matter

Imagine you have a wide landscape shot (16:9) of two people talking, and you want to turn it into a vertical video (9:16). The vertical frame can only show a narrow slice of the original. Without guidance, StarZero Agents will center the frame automatically -- but that might cut off the person on the left or the product on the right.

Focus hints solve this. You describe what matters in each clip, and StarZero Agents keeps that subject in frame.

How to Set Focus Hints

Just tell StarZero Agents what to focus on in your message. You can set hints for individual clips:

"For clip 2, focus on the person in the red shirt."

Or set hints for multiple clips at once when requesting a render:

"Render 9:16. For clip 1: focus on the speaker. Clip 2: focus on the product on the right."

How to Describe Your Subject

Keep it simple and descriptive. StarZero Agents understands natural descriptions like:

• "The speaker's face"
• "The product on the right side"
• "The castle in the background"
• "The logo in the top left corner"
• "The exact center of the screen"
• "The person holding the microphone"

You don't need coordinates or technical terms. Just describe what you see, the way you'd point it out to a friend.

Focus Hints Persist

Once you set a focus hint for a clip, it stays in place for all future renders. You don't need to repeat it every time.

If you want to change a focus hint later, just set a new one:

"Change the focus for clip 3 to the person on the left."

What Happens If the Subject Can't Be Found

If StarZero Agents can't locate the subject you described in a particular clip, it falls back to auto-reframing instead of failing. You'll still get a usable result -- just without the specific subject tracking you requested. If this happens, try a different description that's more visually distinctive.

When No Focus Hint Is Set

If you don't provide a focus hint, StarZero Agents centers the frame automatically. For many clips this works fine -- especially if the main subject is already near the center. But for off-center subjects or busy scenes, adding a focus hint makes a noticeable difference.

Practical Examples

Converting an interview for Instagram Reels:

"Render in 9:16. Focus on the interviewer for clips 1 and 3. Focus on the guest for clips 2 and 4."

Highlighting a product in a wide shot:

"For clip 5, focus on the product sitting on the table."

Keeping a face visible in a group shot:

"Focus on the woman in the blue jacket for clip 2."

Tips

• Focus hints are most important when the aspect ratio change is significant (like 16:9 to 9:16).
• If you're rendering in the same aspect ratio as the source, focus hints have little to no effect since nothing is being cropped.
• Use a low-quality preview render to check your focus hints before committing to a final high-quality render.
• You can combine focus hints with keyframe pan and zoom for even more control.