Got a question here, maybe a silly one, but I'd ask anyway
Does the internal flash of a camera compensate for the exposure by varying the intensity of the flash, or is it a fixed intensity? Yup I know the external flashes do their own metering (TTL, ETTL) and regulate the amount of flash, but does the "cheapo" internal flash do so as well?
Reason why I asked was I tried the following configurations on my C700UZ, indoors with auto-flash:
1) Aperture priority, F2.8, 1/40s, ISO100.
2) Aperture priority, F5.0, 1/40s, ISO100.
3) Aperture priority, F8.0, 1/40s, ISO100.
And for all three configurations I get pictures of the same exposure. And then I tried the following configurations, indoors with auto-flash:
1) Shutter Priority, F3.2, 1/40s, ISO100.
2) Shutter Priority, F3.2, 1/500s, ISO100.
And I get pictures of same exposure as well!
Since exposure settings between the configurations are different, the only reason I can think of that results in even exposure for all images, is that the flash intensity compensates.
And assuming that my guess is correct, I remember using my EOS 300 on P mode, with internal flash. It was at F4.0 and 1/90s (flash sync speed?). When I tried to increase the F number to get deeper DOF, the shutter speed started flashing at 1/90s. Why can't the internal flash of the EOS 300 compensate for the larger F-stop then?
Would appreciate if anyone can share any explanations and insights on this. Thanks!