Just to expand on the above.......I should have explained last night, but was a bit too
As an idea as to how effective is the flash built into the Sony ( and all other slrs) consider this.
I mentioned in an earlier post that whilst correct exposure in natural light is obtained by seting the right combination of shutter speed and aperture, correct exposure for flash is a combination of aperture and flash to subject distance.
So if you know how far away from the flash is your subject you can set the aperture to suit.......and if you have decided to shoot at a particular aperture, you can calculate up to what distance the flash will be effective.
But what is the basis for this calculation, you need a starting point.
All flash units whether built in to the camera, independent and fixed on the camera hotshoe, or in the studio are rated with a "Guide Number" which is an indicator of both the power of the flash and of the resolution of the wee sum mentioned above.
The "Guide Number" on your Sony is expressed as GN12 in metres at 100 iso.
And the calculation is GN = distance in metres x f-number ( aperture)
So lets say you want to photograph an object three metres away from the flash.......the calculation would be:-
12= 3 metres x f-number...................................put another way 12 divided by 3 = 4......so you require an f-number (aperture) of f4
On the same basis as that, if you wanted to use f4 and wanted to calculate up to which distance the flash would be effective, then 12 divided by f4 = 3 metres,
As you can see from the above figures, on your Sony and using the built in flash and taking a fairly wide aperture of f4..........the flash is effective up to only 3 metres ....no good for landscapes. And of course if you wanted to shoot at a decent landscape aperture of say f22....then 22 into GN12 gives an effective range of only about half a meter.
These figures are based on using an ISO rating of 100, if you crank that up to 200 you will get twice the effective flash range......taking the above example up to 6 metres,
Time to get the calculator out...
On any of the camera auto-modes, the sum is taken care of in camera, but whoever does the sums the result is the same...small flash units can be effectively used at only short distances from the subject.