How can I stop iPhoto from importing duplicates of every photo on my iPhone

Having a problem with duplicates of all pics imported from my iPhone

-Connect iPhone

-iPhoto opens, showing the photos on the phone which have not been imported. Problem is that 2 copies of each of the photos are shown as being ready to import. Import otherwise goes as normal.

-If I select "import all," it will import both copies of each photo.

-Selecting and importing just 1 copy of each pic works fine, but leaves a copy on my phone, even if I delete the imported pics.

-The pics are not duplicated on my phone (before or after any import).

I'd appreciate any advice.

Thanks,

-Mark

Mid 2007 20in iMac-(2GHz IC2D), OSX 10.10.2, iPhone 5S