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Old Mar 6, 2006, 9:52 PM   #1
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Lately I've noticed my DS taking rather dim shots while using manual mode. Particularly, I will be at close range to the subject (my face, 1.5 ft away) and use internal flash (1/45 s, f4.5, 45mm). This should be plenty enough light to expose (or even overexpose) the picture, but as I said, the shot is quite dim.

After peforming the same shot with portrait mode (1/60 s, f5.6), the picture is much brighter. I notice on the info screen there is a +1.0 EV for this shot. In manual mode, I should have full control over the exposure: aperture and shutter speed; and consequently, no +/- EV option is available. But, because a flash is present, the timing of the flash with the shutter becomes a whole new variable.

I did find an option in the settings for "flash exposure compensation", which I can increase as high as +1. This did make a difference, but it only brought the picture out of the dim category and is still darker than the portrait mode shot. So, my question is, what is the camera secretly doing to determine the timing of the flash and shutter and how can I tell it to snap the picture closer to the time of flash?
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Old Mar 6, 2006, 10:34 PM   #2
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I noticed this as well and that was what motivated me towards looking at an external flash.

I actually think the cameras cheats to make it feel superior, or am I being paranoid. :?
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Old Mar 7, 2006, 4:36 AM   #3
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Maybe not related to your problem, but one thing that bothers me with my DL, is that when I pop the internal flash up, the shutter speed defaults to 180, even though I'm in manual mode. The picture is usually overexposed, but the camera won't allow me to raise the shutter above 180. Weird?
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Old Mar 7, 2006, 5:42 AM   #4
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Focal plane shutter maximum flash synchronization speed. At any speed over 180 not all of the image will be exposed to the flash and there will be a dark section on your picture. This is because 180 is the highest speed that the camera has the entire sensor uncovered at once, at higher speed the shutter forms a slit to pass over the sensor, the faster the speed the smaller the slit. This only applies to focal plane shutters. Flash units that sync at higher speeds actually produce a number of bursts in a short period of time to simulate continuous light over the duration of shutter travel.

Ira
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Old Mar 7, 2006, 9:34 PM   #5
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After playing around some more, I found the following sure ways of brightening the exposure:
1) increase the flash exposure compensation in setup menu (+1.0 max)
2) put camera in mode other than manual and crank up EV (+2.0 max)

Putting the camera in program mode and setting both above mentioned EV values to their max gives me a very overexposed image. Good: this shows that the camera does have the ability to create brighter images than my previously dim ones.

What bothers me though, is that I thought "manual mode" should be the king of all modes, with which you can take any picture you are skilled enough to take. That is, all the tools the camera can provide are at your feet. But, this is not so. While in manual, the camera times its flash to take rather dim shots, giving you only the "flash exposure compensation" as a means to brighten. In fact, the camera can take much brighter shots - presumably by syncing the shutter closer to the brightest instant of flash, or by discharging varying portions of total flash charge - but the means of further telling the camera to do these things is unavailable in manual mode.

As a side note, I took a picture of my headphones, which were sitting in a dark area on top of my computer - in this case, the camera shot a nice full exposure in manual mode. But when i point it at my face at the same distance, I get a dim shot. Somewhere here the camera is making decisions about light level and is leaving me out of the process. I played with the metering modes, but they didn't produce significant results. I'll continue to mess around...

Can someone confirm or deny any of my my assessments?
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Old Mar 8, 2006, 8:21 AM   #6
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I have experienced both of those problems and ultimately it comes back to the surface being photographed, remember theface will reflect the light back atthelens and therefore the camera will think enough light has been received and cease the flash.

Try changing your metering and make sure it is not on spot.

Again, the internal flash is just not designed for anything other than beginners, get an external flash fr under $200 like the Sigma DG ST (p-TTL) and you will never have to worry about this undr exposure again, trust me on that.

Again, this manual mode versus P mode is interesting, try setting a shot up and adjusting your Aperature/speed to the desired level for a correctly exposed shot.

Take the shot and if it under exposed, set to P mode and repeat the shot, if it is correctly exposed, review the image informationand see what setting the camera used to take this "Perfect" shot.

Go to manual mode and set your camera to the same settings and take the shot again, It would be interesting to see if it does result in the same "Perfect" shot.
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