Combining several apps you most likely find useful for other means as well, this should be accomplishable. So first, let's list the components:
- Tasker: the mighty automation tool will trigger several actions for us
- FolderSync: will do the real copy/sync jobs
- Titanium Backup will do your backups (well, it does already).
No need to elaborate on Titanium Backup, as you already use it. Most likely together with its integrated scheduler, so you have an idea about what time that job has finished.
So the next candidate is FolderSync. It obviously can do with OwnCloud, as described e.g. in Use the Android App FolderSync with ownCloud – using WebDAV, in fact. Which means you've first to setup your OwnCloud account in FolderSync (as described in the linked short-tut), and then define "folder pairs", i.e. which folder on your device should be sync'd with which on the OwnCloud server. Recommendation: configure it for manual sync; as nice as the integrated scheduler might sound, I experienced it woke up the device all 5 minutes 24/7 even with only one daily sync configured. So better leave that integrated scheduler off, we either need something else to trigger your "instant photo upload".
Third candidate: Tasker. You can use this to schedule your regular sync intervals (easy to do, as it's just a time interval as condition, and the FolderSync pair as the task; note this might require the Pro version of FolderSync for Tasker support). But Tasker has also means to detect whether a file/directory has been modified. This is what you can use to trigger your "instant photo upload", by watching your
DCIM folder(s) and trigger the corresponding "folder pair" to be sync'd.
I know you prefered "without an app", but I don't know about such an alternative. However, one of the 3 apps involved you're using already, and once you've got used to Tasker you will ask yourself how you could do without. True, it's "payware", but worth every cent. For testing purposes, a 7-day-trial can be obtained on their project site; export all your config from within the app on day 6, uninstall, re-install, and import it again gives you another 7 days (recommendation by the dev himself). FolderSync requires 3 bucks as well; but it supports so many services, and has Tasker integration, I'd say it's worth the investment. So altogether ~7 bucks for a good solution, and other uses reserved.