Remarkably compact, but sensor too small
I've lost count of how many Canon Elph cameras I've had, some only briefly before I gave them away, others I used regularly. I have several other cameras too (mostly Fuji), but I like the compactness, quality, consistency of user interface, and the best-of-class auto exposure/focus/color of the Elph cameras. I don't like the graininess and limited dynamic range resulting from the tiny sensor. I really feel that Canon should have limited these cameras to 6 Mpixels, because I end up down-sampling everything. The 310 HS is no exception, having both the traditional strengths and weaknesses. It's remarkably compact considering the 3" LCD and the 8x zoom, although they had to move two of the traditional controls to the side to have enough room on the back. I don't think the optical quality of the long-zoom lens is any worse (or better) than earlier 5:1 and 3:1 zooms. The back-illuminated CMOS sensor can be pushed to a higher ISO than the earlier CCD sensors, and the camera makes frequent use of that on the Auto setting, being quite ready to use up to ISO 640 rather than firing the small flash. Photos look good on a small or large screen, but you don't really want to go pixel-peeping at 12 Mpixels, or you will see a lot of graininess and fuzziness. The dynamic range between blown highlights and noisy shadows is quite limited, but Canon's auto-exposure does the a good job of keeping it in the middle for the most part. It does 1080p/24 video capture, but the quality isn't going to be mistaken for a true video camera. The user interface is mostly unchanged, but a few functions have moved from the 4-way rocker to the menu, making them harder to access (e.g., the self-timer). There's a few new functions on the menus, interesting to play with but nothing really outstanding. Overall I give it a thumbs up in the traditional Elph role.