Add a Watermark to an Image

What a watermark does and does not prevent

A visible watermark is a deterrent, not protection. It stops an image being used casually without anyone thinking about it, which covers most of the behaviour a watermark is aimed at. It does not prevent a determined edit, because a semi transparent overlay can be cropped out or painted over, and an aggressive removal tool can defeat a faint one. If an image genuinely must not be reused, the only reliable mechanism is not publishing it. A watermark is a signal of intent, and it works best when it is clearly visible rather than when it is subtle.

NoteA watermark deters casual reuse. It does not prevent a determined edit.

Placement matters more than opacity

A watermark at 50 percent opacity in a corner is easy to crop around, because a corner is a small area and the rest of the image is usually what is wanted. A tiled pattern across the whole frame is considerably harder to deal with, because removing it means editing every part of the image. Placing the mark over a detailed area rather than a flat one also makes it harder to see through. The usual compromise is a semi transparent mark placed over a busy region, sized large enough that it cannot be cropped out without losing the subject.

• Corner watermarks are easy to crop away. Use a larger, central mark.
• A tiled or repeating pattern is much harder to remove cleanly.
• Place the mark over a detailed area so it is harder to see through.
• Size it so removing it would mean removing part of the subject.
• Low opacity is more likely to be cleaned off than a firm one.

A logo watermark and the background problem

A logo watermark carries a problem a text one does not: whether it has a transparent background. A PNG logo with transparency composites cleanly over anything. A JPG logo has no transparency, so it lands as an opaque rectangle, which is worse than useless on a photograph. If the logo is a JPG, remove the background first, or generate a PNG version of it, before using it as a watermark. The same applies to a text mark rendered as a graphic.

• A transparent PNG logo composites cleanly over any background.
• A JPG logo has no transparency and appears as an opaque rectangle.
• Remove the logo background first, or export it as a transparent PNG.
• Check the mark over the lightest and darkest parts of the image.

NoteA JPG logo watermark will show as a box. It must have a transparent background.

Never watermark the only copy

Watermarking is a destructive edit in the sense that matters practically: the watermarked version is the one you share, and it is easy to save over the original. Keeping an unwatermarked master means a change of mind, a different watermark, or a different size later does not require going back to the original photograph. The workflow that avoids the problem is to keep the clean master, and export a watermarked copy for each place it is published.

• Keep the original clean file as your master.
• Export a watermarked copy for each destination.
• A change of mind then needs no rework of the source photograph.
• Use different watermark strengths for different audiences if needed.