Camera models not showing in smart album pulldown
I am trying to create a new smart album based on camera model using Photos on El Capitan. When I have done this in the past, I select Camera Model and Is, and the pulldown shows a complete list of all the camera models I have used to take all the photos in my library over the years, e.g. various iPhone models, SLR, GoPro etc. Now in Photos this is not happening. Instead I get a few version numbers as shown in the screen shot. I'd appreciate any tips to resolve this.
iMac, OS X El Capitan (10.11.2)