J and K Messervy wrote: > I received my flash the other day and have been playing with it a bit > indoors and out. > > First impressions are good, however the exposure results in P-TTL are a > little disappointing. I'm finding that for a shot indoors of my kids or > similar at quite close range, bouncing off the white ceiling, I get spot on > results...but only when I've set the flash exposure compensation to +1. > > Anyone have any suggestions? > > Cheers > > James
OK, here's my suggestions: 1. Perhaps the camera deliberately underexposes slightly with flash - keep it with +1 comp. and forget about it? 2. A lens-specific problem. With P-TTL, the pre-flash is at full aperture, and the strength of the main flash is calculated from this. If the lens stops down to say f/11 when it should be f/8, you'll get underexposure. I've run into exactly this problem recently. Test by comparing images in manual mode (no flash) with the same settings, but do 1 shot with the aperture set in-camera (i.e. lens on A), and another with the aperture set to the same nominal value using the lens aperture ring. Exposures should be identical, so any difference means the aperture actuator (either on lens or body) is miscalibrated. 3. P-TTL seems to use focus distance in its calculations, so perhaps close-up pictures using bounce flash cause the camera to throttle the flash output too much? Again, mis-information from the lens re distance (is it a Pentax lens?) may be a cause. David -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
