1. This is a picture of Tom.

2. This is a picture of Tom's.
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Does #1 mean as follows?
Tom is in this picture.

Does #2 mean as follows?
This picture is Tom's.
This is a picture which Tom has taken.
This picture belongs to Tom.

1. This is a picture of Tom.

2. This is a picture of Tom's.
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Does #1 mean as follows?
Tom is in this picture. yes

Does #2 mean as follows?
This picture is Tom's.
This is a picture which Tom has taken. yes
This picture belongs to Tom. yes