Bracketing Question

[kilifila66]

So I have seen tons of stuff on bracketing (and auto bracketing on dslrs) and I know absolutely nothing about it. I was under the impression it was changing the f/stop on your lens up and down one click to make sure you got the propper exposure, but after reading Jeff Canes post on HIE film it sounds like its changing the iso. I can't even believe how noob this sounds but I have yet to get into the technical aspects of shooting, ive just been puting the film in the camera and firing. Any help and clarification is much appreciated.

Drew

 

[spiralout]

You can change either the aperture, shutter speed or ISO (on digital), and they'll all work for bracketing. The question is just which one to bracket, depending on your shutter speed or DOF preference.

 

[Unimaxium]

This should pretty much explain it for you:
http://www.photoxels.com/tutorial-exposure-bracketing.html

And you can find plenty more of descriptions of bracketing here:
http://www.google.com/search?q=bracketing

 

[ksmattfish]

I was under the impression it was changing the f/stop on your lens up and down one click to make sure you got the propper exposure, but after reading Jeff Canes post on HIE film it sounds like its changing the iso.

Bracketing is intentionally over and under exposing from the "normal" exposure. It's useful for slides and transparencies because even 1/3 of a stop is noticable. It is useful for IR film photography because usually the photographer has no way of measuring the IR falling on a scene.

You can overexpose by opening the aperture (smaller #), slowing the shutter, or increasing the ISO. You can under expose by closing the aperture, speeding up the shutter, or decreasing the ISO.

 

[kilifila66]

Thanks everyone! I guess I knew what it was in terms of compensating for exposures but I had NO IDEA you could do it so many ways. I need a digital so I can learn this stuff and not pay 10 bucks a roll for a set of prints! Thanks again for all your help, i shall hopefully have some results to post soon.

 

[wharrison]

kilifila66:

Of course, if you wish to sound snobish or overly "astute", you could use the term: "calculated safety shot" (Ansel Adams) instead of the "pedestrian" term "bracketing".

Bill

 

[craig]

Personally bracketing is not all it is cracked up to be. When I was shooting a lot of BW film I had the advantage of a densitometer to read my film. For my camera and film type I could figure out that if I shot Tri X at 200 ISO as opposed to 400 I would have a strong neg. Once I had that down I could concentrate on different approaches to a scene as opposed to wasting frames on different exposures. Of course contrasty lighting situations call for a variety of exposures to achieve the desired effect. In a case Like that I go 3 over and 2 under. My preference is to keep the aperture and change the shutter.

I approach digi the same way. I take an initial reading, compensate and then leave the exposure at that.

Keep in mind that camera meters, film and digi will give a reading of details in the shadows and the highlights. I have always considered that as a good starting point, but flat. As the photographer you will choose how the scene is exposed.