[This highly-upvoted SO answer](https://stackoverflow.com/a/5613926/87698) recommends to put images in separate tables, even if there is only a 1:1 relationship with another table:

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> If you decide to put your pictures into a SQL Server table, I would strongly recommend using a separate table for storing those pictures - do not store the employee photo in the employee table - keep them in a separate table. That way, the Employee table can stay lean and mean and very efficient, assuming you don't always need to select the employee photo, too, as part of your queries.
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Why? I was under the impression that [SQL Server only stores a pointer to some dedicated BLOB data structure](http://sqlmag.com/t-sql/varbinarymax-tames-blob) in the table, so why bother to manually create another layer of indirection? Does it really improve performance significantly? If yes, why?