Exactly. And, if you can produce readable content along with those photos you post. Google also need those words to understand each of the photo you blog. And the content will also be one of the basis of ads appearing on the adsense unit you put on your photo blog.
yes! you can. And put in the correct area. Google don't allow you put adsense below th picture and make the user mistake click.
I've seen lots of blogs like yours that have adsense. Just add a little description on your photos to make it crawlable by spider.
I don't any problem should happen. There are many many Image websites or blogs running AdSense. Most of them are very popular.