Nikon D50 - What settings effect quality?

The best thing about having any digital SLR is the ability to preview what was just shot and deleting it if you don't like it. Bracketing the shot 3 steps above and below is good insurance for getting the shot right.

The settings on the camera are based on taking a picture with an ISO400, f-stop of 11 and shutter speed of 500 in sunlight (5500 kelvin). The trick is knowing what to adjust when you deviate from any or all the settings. Remember, technical quality doesn't necessarily mean the shot was set up correctly. One rule that comes above all others is: use a tripod whenever possible. A bi-pod is next best and proper stabilization when hand-holding the camera come last. Whenever possible use a remote trigger. The rest is pretty much in the eye of the photographer.

Over the years I have tried to be true to the rules. But sometimes getting the right shot require a little cheating. Practice, practice, practice. You can't do it enough. With practice you won't have to think too long on what settings are best for the shot. Learning a few simple tricks will open up the creativity in you.

Google "digital photography". You will find a plethora of sites with great information. You'll find that learning this craft is a never-ending proposition. Enjoy!!

and life goes on...

Jack

White balance is not for adjusting brighter or darker.

It is for adjusting color balance.
If the colors look natural...white balance is fine.

Your camera has a light meter built-in, and when in automatic mode, will select the right aperture and shutter speed for a perfectly exposed photo.

In the old days when cameras did not have light meters, the photographer carried a light meter.
Since light meters were expensive, you could also get a device that looked like a circular slide rule. You would input the type of lighting (i.e. bright sunshine, outdoor shade, cloudy bright, etc) and the speed of the film you were using.

The slide rule would tell you the approximate aperture setting (f-stop) and shutter speed.
You could play with this information.
You could raise the shutter speed by one stop, but you would have to change the aperture by one stop to let in more light.
If you lowered the shutter speed by one stop, you had to change the aperture by one stop to reduce the amount of light.
Your D70 does this for you.

In shutter priority mode, you select the shutter speed and the camera will use its light meter to determine the correct aperture setting for a perfect exposure for that shutter speed.

If you have selected a shutter speed that is very fast, the camera will select a "brighter" aperture setting (f-stop).

Let's say your lens is rated at f2.8 and you selected a very fast shutter speed.
It is possible that the camera needs more light than your lens can provide at f2.8
Then the camera will adjust the ISO setting upward to provide the proper amount of light.

(You can consider ISO settings as a volume control for light. But just like a radio volume control, if the turn it too high you get distortion. With a camera this is called "noise" which produces a grainey appearance, particularly in the dark areas of the photo).

The camera will play with the aperture setting and the ISO setting to give you the best results. The camera makers will not tell you the exact protocols they use to make that decision.

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Since you are interested in more details of photography, you should consider taking a course in photography.

Here is a free short course that should get you started:

http://www.shortcourses.com/using/index.htm

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