Unlock Longer Videos: Prompting NotebookLM for Extended Overviews

NotebookLM's new Video Overview feature is a game-changer for quickly summarizing your research. But if you're like me, you've probably noticed it often produces videos that feel a bit too short for a deep dive or a proper YouTube explainer.

The good news? You can "steer" NotebookLM's AI to produce longer, more detailed videos by providing it with the right instructions. Think of it as giving the AI narrator more "fuel" for its storytelling engine.

The Challenge: Getting Past the "Brief Summary"

By default, NotebookLM aims for conciseness. This is great for quick recaps but less ideal when you need to cover complex topics thoroughly. To lengthen the output, we need to instruct the AI to slow down, elaborate, and dive deeper into the nuances of your source material.

The Solution: A Strategic "Custom Instructions" Prompt

Here's how to do it:

1. Prepare Your Sources

Make sure your NotebookLM notebook contains not just your slide deck, but also a more detailed text document (like a full script, article, or transcript) that covers the same topics in depth. This "anchor document" is crucial for providing the AI with enough material to talk about.

2. Access "Customize"

In your NotebookLM Studio panel, click the "Customize" (pencil) icon on your Video Overview tile.

3. Enter the "Steering Prompt"

Copy and paste this prompt into the Custom Instructions box:

Video Format: Explainer (Comprehensive)

Instructions:

- Length Extension: Actively aim for a 10-12 minute duration. Do not move to a new topic until you have exhausted every detail from the 'Video Script Bridge' source.

- Pacing: Adopt a "Documentary Narrator" persona. Use pauses for emphasis and provide deep, sentence-by-sentence analysis of the data points and diagrams found in the PDF.

- Structure: Provide a 90-second thematic introduction. For each core chapter, use a 3-part structure: Explain the concept, analyze the specific data from the slides, and then provide a real-world synthesis.

- Retention: Include mid-video summaries every 4 minutes to recap complex points before moving forward.

(Pro-Tip: Replace 'Video Script Bridge' with the actual name of your detailed text document in NotebookLM.)