After replacing the content of a smart object layer, why did the image get enlarged?

[javaer]

The initial state of the PSD 

Right-click on the smart object layer and select "Replace Contents."

After replacing, the image was enlarged.

Please refer to the attached PSD and replacement image.

 

[D Fosse · Accepted solution]

Smart objects honor the physical print size, not the pixel size. This means you need to watch the ppi values for consistent size. The ppi numbers need to be the same.

This may seem counter-intuitive and against Photoshop's natural behavior - but it was intentionally designed this way for compatibility with PDF and vector data. This is just something you have to keep in mind when working with smart objects.

[Stephen Marsh · Accepted solution]

@javaer – Further to the reply from @D Fosse

PNG replacement image:

1018 x 1907 px @ 96 ppi (mismatch in PPI)

PSD smart object layer contents:

1019 x 1907px @ 300 ppi (target PPI)

PSD template image:

300 ppi (not important, I'm just noting this for consistency)

[javaer]

Thank you both very much for your responses. The replacement works properly now.

[javaer]

Is your conclusion that the PPI of the replacement image and the smart object layer content should be consistent?

[Stephen Marsh]

Is your conclusion that the PPI of the replacement image and the smart object layer content should be consistent?

By @javaer

Yes.