Document size confusion

I've never had this problem before in Photoshop, but I have an image, and I have no idea what its actual size is.

When I click "Image Size" the information it gives me is as follows:

Pixel Dimensions:
Width: 5434 Pixels
Height: 4080 Pixels

Doc Size:
Width: 17 Inches
Height: 12.764 Inches
Resolution: 319.647


So where is the confusion you ask? I KNOW this image is larger than 17 inches (wide)... when I click "Actual Pixels" for 100% zoom, its at least double what those measurements are saying, very crisp and clear image at that size too.

The rulers at the top and side of the screen are also incorrect. They are set to "Inches" however when the image is at 100% zoom, 1 inch is more like 2.5 inches. Only at 31.8% zoom is where 1 inch is actually 1 inch.

I'm trying to have a large print of this image done, but this size discrepancy is giving me problems... can anyone shed some light on this?

My guess is that the discrepancy you're seeing is due to the resolution (DPI) of the image.

If you zoom in to 100% you're going to see every pixel in the image. If the resolution of your monitor is only 128 DPI, then if you view a 320 DPI image on the screen at 100% zoom, every 1 inch of the image is going to show up as 2.5 inches on your monitor due to the fact that your monitor is physically incapable of display 320 pixels in 1 inch.

320 is a high DPI level; most computer monitors are substantially lower than this.

That was it! Thanks for explaining this to me, I just have never seen an image like that before. I enlarged the image, and unchecked "resample image" and it maintained its quality and sharpness.