ガイド
再利用前にYouTubeサムネイル品質を確認する方法
サムネイルを使う前に画質を見極める実践チェックリストです。
参照用途でも、先に品質確認をしておくと後戻りを減らせます。
Start with the largest available image
Always inspect the highest resolution first.
If the largest version looks weak, smaller versions will not improve quality.
Inspect text and edge sharpness
Zoom in and verify that text edges are readable, not smeared.
Look at faces, logos, and high-contrast lines for compression noise.
Check real usage size
A thumbnail can look acceptable when tiny but fail at slide or article size.
Preview it at the size you plan to use before finalizing.
- Test at 100% zoom.
- Check on both light and dark backgrounds.
- Avoid aggressive upscaling.
Document source and intent
Save where the image came from and why it was used.
This keeps team communication clear when references are reviewed later.
Quick quality checks for
- Decks and reports.
- Creative benchmark boards.
- Team feedback sessions.
Check quality before you commit
A 30-second review avoids blurry visuals and saves rework later.