That's not correct

[Soleil]

Hello,
Can I say "That's not correct." if I'm reading a text and showing at the mistakes in the picture that is supposed to match this text?

 

[emsr2d2]

Hello.
Can I say "That's not correct no full stop here" if I'm reading a text and showing at the want to say that there are mistakes in the a picture that is supposed to match this a/some text?

Note my changes above.
You can say it as long as it's clear whether "that" refers to the text or the picture, or if you're trying to simply say "The two things don't match".
Can you tell us more about the context or situation in which you want to use it?

 

[Soleil]

Note my changes above.
You can say "That's not correct" as long as you make it clear somehow whether "That" refers to the picture or theI'm

I'm reading the text and pointing at the same time at the mistakes in the picture. So, I can say "that is not correct" even if the picture is not far from me. Am I right?

 

[emsr2d2]

Yes, in this context "that" doesn't really have anything to do with proximity. It's simply being used to be specific about which part of the picture is wrong.