A blog is past, present and future. A photo can freeze present and hold a personal connection with the past.
A blog nudges someone (the writer) to pluck invisible text out of a language and create a visible passage. A photo is a scene that says ‘take me now!’
Both use their own devices – grammar and spelling, focus, depth of field and speed.
A bunch of photos can be a blog, but a bunch of blogs can’t be a photo.
Both can show beauty, brevity, complexity or horror. From the same person, they can have the same style. Or not.
A series of photo’s might become a movie. A series of books might become a series of movies.
A photo can sum up a thousand words. And a blog can sum up a thousand photos.