Photos does non-destructive editing, preserving the original image for you so that you can redo/undo what you did, although I don't think you can actually edit something you've added, just revert it away and re-enter.
Now when i plug the iphone into the mac mini and launch image capture it says the phone needs to be unlocked, so i input the passcode into the phone, but nothing happens in image capture and im not able to download the images. If this is how you want to work, you might consider changing the editor you use from Preview to Photos. Ive recently updated my iphone to a iPhone 6s running iOS 10.x (latest). That only works if TM is turned on, obviously, but it might be of some use.
and see if you have an old image in Time Machine that you can pull back from before it was saved. Ok, that said, you might try opening the image in Preview, then click on File/Revert to. From your sequence, you are saving the edits and then renaming the file, but at that point the edits have already been saved and the original file overwritten. (Touch ID will unlock the display, but you should always be prompted for your passcode to trust the Mac. Connect your device to your computer using a cable, then turn the device on. Once you transfer the items, you can choose to delete them from the device. Follow the instructions to adjust your finger position to capture the. What you might think about doing is to rename the image at the time you OPEN the document and well before you start to make the edits and preserve the original image with NO edits just in case you want to restore later. You can use Image Capture to transfer images and video clips to your Mac from a camera, iPhone, iPad, iPod touch, or other device that has a camera. If you dont already have a screen lock, youll be asked to add a backup PIN.
The edits, when saved, become a permanent part of the new image. You can use Image Capture to transfer images and video clips to your Mac from a camera, iPhone, iPad, iPod touch, or other device that has a camera.