[iExplorer][1] calims to grant you root access to iDevices without requiring a jailbreak:

> With iExplorer, you can access more files and folders without modifying (jailbreaking) your device than ever before. Need to access photos on your iPhone or iPod? Can do. Want to access the files and folders of your device's apps? Done. How about browsing through your iTunes backups? Check. What about the media folders containing your iTunes purchases? We've got that too. What about files in apps that are synced to iCloud? Yes, even that.*

[iBrowse][2] is a simillar, free software by the same company, but it doesn't grant root access (which I'm not sure you need in order to access photos).

I also found [a guide][3], written in 2008, and doesn't involve any 3rd party software: (Not sure it still works)

> 1. Connect your iPhone/iPod touch and launch Applications >Image Capture.
> 
> 2. Go to Preferences >General.
> 
> 3. Under Camera, select Image Capture in the “When a camera is connected, open:” option, and then click OK. Now when you connect your
>  iPhone/iPod touch, Image Capture will be launched and you can choose
> where you want to download your images.

 


  [1]: http://www.macroplant.com/iexplorer/
  [2]: http://www.ibrowseapp.com/
  [3]: https://www.iphonelife.com/tip/how-to-get-photos-off-iphone