Nikon D300 (A,S,P Modes Automatically Changing)

Okay, maybe I'm missing something here. But I had my Nikon D300 for close to a year now. I have started

experiencing problems with this camera when I place the camera into A,S, or P modes. For example, when I place

the camera in Aperture priority mode, the camera places the shutter speed in an unrealistic shutter speed (an

extremely low speed i.e. f6.3 at 1/15 and another example the shutter speed keeps going up and down constantly

even when I'm trying to take a pic). This happens when I adjust to other specialize priorities on my camera.

However, Manual mode works just fine. I change lens, it still happens. I'm thinking it's something internally

wrong with the camera. Any advice?

Try cleaning the contacts between camera lens with a soft cloth, no solvents.

 

By unrealisticly low you mean one that will give overexposure?

 

Try another lens or camera with your lens to detirmine where the problem is. I would definately get it repaired before the warrantee expires.

If you are constanty seeing a very slow shutter speed, I suspect your ISO is set to 200 constant. Try using a variable ISO and see what that does to your shutter speed.

In any auto-exposure mode the meter reading will adjust rapidly to accommodate changing illumination. Even if the illumination doesn't change the reflected light will change slightly as you move across the subject, so it's perfectly normal for the meter reading to change slightly as, for example, you pan across a wall, carpet, fabric, group of people, etc., in any typically unevenly illuminated scenario.

 

In manual mode we don't see these changes because we select the aperture and shutter speed. That doesn't mean the scene is perfectly evenly illuminated or reflecting light exactly the same way from all surfaces. And the meter will continue to indicate those changes (a needle in older meters, a bar or other indicator in most later cameras).

 

If your exposures appear accurate despite, for example, the slow shutter speeds, then either select a faster ISO or use more lighting.

I had a D100 that was giving me fits in a similar way... it turned out that the selector switch was broken, and when I put it in A it was really in P, or whatever the next dial setting was. It was still useable, but the dial was just in the wrong place. Each setting was off by one, or really about a half, because sometimes it would work okay if you tweaked it just right.

 

Check to see if thats the issue!

Lex is right. Perfectly normal for the camera to adjust the shutter speed or aperture very quickly in response to changing

light in the scene, either from changes in the light source or changes in what is included in the scene (framing). That is the

reason you use one of the automatic exposure settings-- you can set the aperture or shutter speed that is most important to

you and the camera will adjust the other much faster than you can in manual mode.

 

If the camera selects a shutter speed/aperture combination that results in a properly exposed photo, then that is not

unrealistic. It may, however, be unrealistic for hand-held photography, in which case you need to open your aperture more (if

in aperture-priority) or increase your ISO setting if you must use the aperture that you've set (for DOF results, etc.).