Usually I definitely avoid any type of critique unless the photo is actually in the critique section. I just think that if the person wanted critique/advice etc they would have put the photo in critiques and not Show Your Photo.
I have recently kinda of gone against that a couple of time with Casil and Bambi but only on points we'd discussed in critiques beforehand. I took it as an opportunity to just reinforce/point out those things again.
I'm certainly happy for them or anyone else to ask me not too if their photo is in the Show your Photo section, although as stated, it would be rare for me to give them the opportunity anyhow.
Occasionally many of us forget to check which forum we are looking at and give critique when a photo is in the Show your Photo section ... and vice versa really at times. A gentle comment to highlight where the photo is is usually enough I think.
Exceptions to all that is someone like me who has in their signature that critique is fine anytime (well I used to) I'm often interested in what people find interesting/well done, or not, in my photos.
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