Since photographers like to display their work, it is important to read terms of service. Where Google+ may not actually make use your images, I would be cautious about what I post. Here is an excerpt of the terms of service:
“By submitting, posting or displaying the content you give Google a perpetual, irrevocable, worldwide, royalty-free, and non-exclusive license to reproduce, adapt, modify, translate, publish, publicly perform, publicly display and distribute any Content which you submit, post or display on or through, the Services. This license is for the sole purpose of enabling Google to display, distribute and promote the Services and may be revoked for certain Services as defined in the Additional Terms of those Services.
If this is not the right forum, please repost.
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