When I select Pantone Process Blue PC in Photoshop, the initial selector agrees with C:100 M:13 Y:1 K:3. I then painted an area that color, and the info window said it was C:77 M:26 Y:0 K:0, which is probably a remap for gamut and to keep the total ink closer to 100%. If I start with a CMYK image, it keeps the original value, but does the above when I convert to RGB.

Anyway, it says the equivalent is R:0 G:152 B:214 which sounds reasonable, and doesn't shift color to my eye. (besides I trust PS)