05/07/2018
Any comment is useful. To comment demonstrates you have engaged, which in itself is great acknowledgement for a photographer.
Brief praise (‘cool, ‘wow’ ‘this is stunning’ etc) is flattering - who doesn't like that? However, more detailed commentary about what specifically moves you to comment is more useful to me- ‘I like this because…’. Since they are then at liberty to choose to learn from the comment.
I'd go further to say that negative comments can be equally useful. I don't know any serious photographer who doesn't recognise their limitations with the consequential urge to act upon them.
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