Coverage and Range
A powerful flash at close range, with pretty good results even at full telephoto. Our standard shots required less than average exposure compensation, and coverage was pretty uniform at both wide and telephoto ends of the focal length range.

26mm equivalent	520mm equivalent
Normal Flash using Auto AE , Default	"Slow-Sync" using Aperture Priority AE, -0.3 EV

Coverage and Exposure. Flash coverage was only very slightly uneven at wide angle, better than average, and significantly so, considering the FH20's 28mm equivalent wide angle limit. At full telephoto, coverage remained fairly uniform. In the Indoor test, the Casio EX-FH20's flash exposed properly at the default setting, requiring no exposure compensation. An average of +0.7 EV is needed for this scene, among the cameras we've tested. While the FH20 doesn't have a dedicated Slow-Sync flash mode, we noticed when using Aperture Priority AE, the shutter speed dropped from 1/20s to 1/4s for this scene. Results with this slow shutter speed were a little too bright at its default setting, requiring a -0.3 EV exposure compensation adjustment to get a good exposure. There's an orange cast from the background incandescent lighting because of the slower shutter speed, but results are pretty good here.

Flash Range: Wide Angle
6 ft	7 ft	8 ft	9 ft	10 ft	11 ft
1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100
12 ft	13 ft	14 ft	15 ft	16 ft
1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100	1/15 sec f2.8 ISO 100

Flash Range: Telephoto
6 ft	7 ft	8 ft	9 ft	10 ft	11 ft
1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100
12 ft	13 ft	14 ft	15 ft	16 ft
1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100	1/15 sec f4.5 ISO 100

ISO 100 Range. At wide angle and ISO 100, flash shots remained bright all the way out to 16 feet. At full telephoto and ISO 100, flash shots were brightest to about 9 feet, and fell off slightly with each additional foot of distance. Good results here, however the 1/15s shutter speed chosen by the FH20 in Auto exposure mode is a little slow. That doesn't impact our flash range test, since the flash is providing all the illumination (no contribution from ambient light), but it could lead to blurry flash shots in the real world. When we shot the same series in Aperture Priority mode, the shutter speed dropped to one second, which many other cameras will only do when Slow-Sync flash is enabled. Users would be wise to use the FH20's Shutter Priority mode if they need faster shutter speeds to avoid blurry flash shots.

Manufacturer-Specified Flash Range
Wide Angle	Telephoto
23 feet ISO 400	14.4 feet ISO 400

Manufacturer Specified Flash Test. In the shots above, the EXILIM EX-FH20 performs as Casio says it will, producing a good exposure at the rated distance with its ISO set to Auto (which selected ISO 400). This time, the camera selected a reasonable 1/50s shutter speed at wide angle, but again selected a relative slow shutter speed (1/15s) at full telephoto, where a faster shutter speed would have been more appropriate. Our standard test method for flash range uses a fixed setting of ISO 100, to provide a fair basis of comparison between cameras. We've now also begun shooting two shots using the manufacturer-specified camera settings, at the range the company claims for the camera, to assess the validity of the specific claims.