Canon 7D Mark II Flash

Coverage and Range
Good flash range, though with somewhat narrow and uneven coverage. Less than average positive exposure compensation required.

Coverage. Canon rates the EOS 7D Mark II's internal flash coverage at approximately 15mm, though as you can see in the above shot taken at 18mm, we've found manufacturers' coverage ratings are usually quite optimistic. Peripheral Illumination Correction was on (by default) for this shots, so the fall-off seen here in the corners and vertical edges is mostly from the flash. Coverage is also little uneven vertically, with a couple of dimmer horizontal bands. We doubt you'd notice this in most read-world flash shots, though.

Exposure. Indoors, under incandescent background lighting, the Canon 7D Mark II's flash performed very well, requiring less than the typical +0.7 EV positive exposure compensation needed for this test scene with a shutter speed of 1/60s. The camera's slow-sync flash mode didn't require exposure compensation for a good exposure, though the longer exposure (1/20s) resulted in a warmer orange/yellow cast from the ambient background lighting.

Manufacturer Specified Flash Test. The Canon 7D Mark II's built in flash has a rated Guide Number of 11 meters or 36.1 feet at ISO 100. That works out to about 10.3 feet at f/3.5, the maximum apertures of the 18-135mm lens at full wide angle. In the shot above at those settings, we can see that the Canon 7D Mark II's flash did not quite perform to specification, producing a slightly dim target at the rated distance. It's not too far off the mark, though, just about 1/4 EV underexposed.