How to delete the photos off of my iPhone but keep them on my computer?

I have roughly 3, 800 photos on my iPhone, is there anyway that when I plug in my phone to my Mac I can put all of these photos or some that I select onto my computer without losing them completely. So I want to keep them on my computer but get them off of my phone. I'd greatly appreciate step by step directions if anyone can help!

It should be easy. Just connect your phone to your computer, click import photos, and save them in a folder. I do this all the time.

Down load itools it lets you drag n drop from idevices.

Back them up on itunes

Cut and paste directly from iphone to computer http://www.justtext.com/messageboards/20130202133028.html

Transfer your iPhone photos to computer before delete them.

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