Turning off iCloud Drive won't stop photos from going to iCloud from your devices. It's iCloud Library (under Photos' settings) that automatically stores your photos in iCloud.
- iCloud is an nearly all encompasing term that includes pretty much every storage, syncing, backup solution by Apple.
- iCloud Storage is the the free and/or payed for storage attached to yoru iCloud account. Some services count agains't that limit, and some do not.
- iCloud Drive is a folder-system-like service that is hosted on Apple's iCloud Servers and syncs between your devices and computers. It counts against your iCloud Storage.
- iCloud Photo Library is a photo and video library hosted on Apple's iCloud Servers and synced between your devices and computers. It counts against your iCloud Storage. It is not part of iCloud Drive's folder system.
And many other services, including Music, iBooks, backups, Mail, Calendars, Reminders, Notes; all have some iCloud components. Some free, some payed for, and some so nearly transparent you won't even realize they are using iCloud unless something goes wrong.
Anyway, if you don't want your Photos library in iCloud, it's the iCloud Photo Library that needs turned off.