It seems too good to be true. Unlimited storage. Free. What’s the downside?
Google using the photos and the gigabytes of personal information about you they already have to replace you with a Synth clone loyal only to Google.
Stranger
Although your pictures are not shown to others, Google can probably use them internally to train its neural networks to recognise dogs, boats and your cousin Jenny. Which they’re already extremely good at doing in many cases (try searching for “car” or “plate” in your own Google Photos, then look at your automatic album showing People and Pets). They’re still working on the gorilla problem (->Wired), though.
I’m sure they’re scratching their heads looking for ways to monetize their ability to identify individuals and infer “real” social networks by linking people together through the pictures they take of each other. That was probably more relevant when Google+ looked a bit more promising.
Well, aside from being Google (which I still begrudgingly use), I do believe there is a limit in image size for free option (they will automatically resize it). I don’t remember what it is, but it is good enough for my needs.
Seems like a good idea for Google:
<Boardroom>
“We have a cool new neural net/AI/Skynet/HAL that we need to teach, but we’ve run out of photos to train it. What can we do?”
“How about we let people upload their photos to our servers for free, as many as they want? That should be good right?”
“Outstanding!”
Obligatory quote:
When they get hacked, everyone will see your celebrity nudes. Which probably matters less when you’re not the celebrity in question.
I don’t think there’s a serious problem as long as there’s nothing too “personal” in there.
So no nude pictures (whether of yourself, someone you know, porn, whatever) and no scans of your passport, plane tickets, or whatever information could compromise your identity. Same sort of rules for putting pictures on Facebook (even if “private”).
I have a digital camera, but not a smartphone, so pictures I take don’t have GPS “tags”, but most pictures these days are taken by a smartphone that, for some inexplicable reason, adds your GPS information to the image. I don’t know how serious a privacy issue those GPS tags are.
I’m sure they’ve already figured out plenty of ways to monetize it. And I don’t think that Google+ went away, so much, as it got transparently integrated into everything else we use.
I had no trouble just now looking for images of gorillas.
A large percentage of digital cameras sold today also have GPS tagging.
Up to 16 megapixels, and only up to “high quality”, which is more compressed (lower image quality) than the original image file. You can see a comparison in this article.
You can pay for an upgrade which will allow you to store “original quality” images. Owners of the Google Pixel phone also get that feature.
Not if you turn off the GPS. I keep it “off” by default except for the rare occasions I actually use GPS. Really that’s not off in the sense of the phone not tracking GPS/wife estimated location. It’s off in the sense of not sharing location data with apps. I do get that there are people who use GPS to go almost everywhere and take almost as many pictures daily as I do annually. Still, depending on UI it can be really simple to change the location services setting. It’s one swipe and a tap for me.
Under Android there’s two other built-in options that can prevent you from sharing location data in photos. The Camera app let’s you turn off saving location in pictures you take. There’s also the option in Google Photos to remove saved location data from pictures already taken before sharing elsewhere (although at that point Google already knows.)
Which doesn’t mean Google isn’t still gathering valuable data, including location, on you from pictures. One of the services mentioned at the end of the link above is the ability of Google Photos to add an estimated location to a picture. Which is one of the catches to answer the OP. Even if you are removing that estimated location from the files before sharing, Google Photos use of photo recognition gives them the data that is worth money to them. Since most people are using default settings they typically have actual GPS data anyway.
Resizing also greatly reduces the ability to use steganography to hide data, making it just a massive storage location. Only visual data will survive.
(It would technically still be possible, but it would get very unwieldy to try and encode things in the pictures.)
Were you doing a search that required google to identify gorillas itself or were you just doing an internet search? The problem is not that Google can’t search for gorillas.
I’m disappointed that I can’t select a photo in my Google photos and ask it to find more “like that”. I don’t want cats or dogs or Bob or Henry, I want it to find photos that look similar to one I’ve selected (a photo of a form.)
You can, actually. If you right click on your photo you can reverse image search which will show you similar images.
I want it to find similar photos in my own collection only.
Thank you for that link, it was very helpful.
I used Picasa for years and then boom!
After many tries on other sites, cost or adds or limits or hassle for me or problems for you to look without stress I went back to google pictures and dove deep.
As always, I post process. I never just send straight from my phone as it is PITA to make the pictures smaller with fewer K so it goes faster and eats less data for me & you.
So now I just use Google Pics, a little harder for me but I have a routine both for batch processing with IrfanView and Google Pics that I can go pretty fast.Best COB way I have found.
If I hosted my own on an always on computer set up as a picture viewer using ‘Apache’ it would be easiest but that would cost $$$$ and as I said, I am a COB. 
data point of one.