The SD10 has no built-in flash, but the camera's hotshoe will accept powerful external flashes, including two Sigma TTL-dedicated strobes. Flash-sync speed is a decent 1/180 second.Like the SD9 before it, the Sigma SD10 offers adequate performance but still lags a step or two behind the competition. Shutter delay varies from about 0.3 second to 1.5 seconds with autofocus, and it's about 0.2 second with manual focus. Shot-to-shot time is slightly more than a second. In continuous-shooting mode, the camera fires at 2.2 frames per second for a six-shot burst, after which a 7-second buffer stall sets in. These figures range from mediocre to poor for a dSLR.
The SD10's autofocus system is a throwback to the early 1990s. It hunts around too much in both good light and bad, and it can't track moving subjects that other midlevel dSLRs handle easily. This, combined with the unimpressive numbers mentioned above, makes the SD10 a bad choice for sports and action shooters.
The camera's "sports finder" viewfinder shows roughly a 25 percent wider field of view than your image will actually record. The area that won't be captured is clearly distinguished by a semitransparent gray mask. We liked the ability to see what's just outside the frame area, but the actual image area is fairly small in the viewfinder, which makes manual focusing more difficult. The camera's LCD is sharp and reasonably easy to use for reviewing images, even in bright light.
Unlike the SD9, all of the SD10's digital and mechanical operations are powered by one battery system--either two CR-V3 lithium batteries or four AA cells.