Difference between と and とは？

For example in below sentences

> そんなに大きいと思わなかった。

and

> そんなに大きいとは思わなかった。
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2015-06-03T00:58:20.710
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2023-08-28T14:17:26.897
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question
usage particles
Difference between と and とは
_In this case,_ there is very little difference, although the latter strikes
me as a bit more common.

I would categorize the は in the latter sentence as a contrastive wa: "(I knew
it was big, but) I didn't think it was this big".
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2015-06-04T03:39:13.093
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2015-06-04T06:40:43.760
2015-06-04T06:40:43.760
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answer
I think the は in とは is an emphasis on と
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2023-08-28T14:17:26.897
100824
2023-08-28T14:17:26.897
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answer