1. Canvas vs. delivery resolution
Blurry output often means you are scaling small screen captures to a large frame. Set your Camtasia project dimensions to match where the video will live (for example 1920×1080 for typical web). If you must upscale, expect softness; prefer re-recording at native resolution for critical UI text.
2. Effects stack and preview lies
Heavy blur, shadows, and stacked color grades increase render complexity. Temporarily disable effects in halves (binary search) to find the culprit. If preview is smooth but export fails, suspect disk space, path permissions, or a problematic clip near the timeline edge.
3. Codecs and generation loss
Re-encoding the same MP4 repeatedly softens detail. Keep a high-quality master file for edits, then compress once for web. If a platform re-encodes uploads, upload the least-processed file their guidelines allow.
4. GPU drivers and background apps
Update GPU drivers on a stable schedule—not only when things break. Close browser tabs with heavy WebGL, pause cloud sync on project folders, and export to local SSD instead of network drives when possible.
5. Audio sample rate mismatches
Rare but painful: mixed sample rates across clips can create edge-case export problems. Normalize inputs at capture time when you can, or convert upstream before import.
Quick diagnostic checklist
- Does the issue appear in preview, or only after export?
- Does a short 10-second test export succeed?
- Does the same export work with a blank project?
- Are you out of disk space or writing to a full volume?
Pair this with cleaner captures and cleaner audio to reduce how often you push the encoder hard.