In stitches, a one-eyed cat and a question about copyright

from w
Once upon a time when I had not much to do in the cold evenings, I stitched a 'House that Jack built' picture of a rooster cat and mouse. A bead eventually fell out of the cat's eye. The naive kind of tapestry hung on the bedroom wall for a while. I photographed it and then did a reverse colour with Microsoft photo-edit, but I think the original warm colours suit it best.

Now the question about copyright:
what if I scan someone's photo from a magazine,
crop a corner of it,
manipulate it with a photo-editing program until it's barely recognizable,
and now want to use the altered image in a book,
do I have to acknowledge the original photographer?

(later) I did a google search and it seems that this is a no-no if I want to use my 'version' for more than just a picture in my scrapbook, and I should request permission from the original photographer to 'mess about' with his or her picture.


And here are a few bits and pieces from photographs I took in recent days.
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later - Tuesday, Dec 1. I made a coloured pencil picture of the 'House that Jack Built' based on the stitched one, and then changed one slightly to cooler colours. It might be good in a children's room.