bracketing under natural lighting

[chat_sirichanvimol]

Ok -

I'm trying to capture my subjects under natural light and it was

suggested to bracket when in dought. That said, when bracketing

would you use apeture priority where the shutter speend is

automatically calculated or do you want to hold the shutter speed

fixed to control the how long the light is hitting your negative

while you bracket the f-stop or does it not matter?

 

Thanks

[kevin_hundsnurscher]

You can either change the speed and keep the same aperture setting<br>

or<br>

change the aperture setting but keep the same speed.

[richard_cochran]

How did you choose the aperture/shutter speed combination for your

original unbracketed exposure? You can probably choose the

settings for the bracketed exposures using the same logic.

If you thought a particular depth of field was vital to your creative

vision, don't change the aperture just for the sake of bracketing

exposure. Likewise, you may have chosen a particular shutter speed

to properly capture a moving subject like a waterfall, and it may

be best to keep this shutter speed for the bracketed exposures.

In other situations, it may not matter very much.

<p>

If you were confident of exposure value, but you weren't sure

what aperture would yield the correct depth of field for

the situation, you might do a different sort of bracketing,

altering aperture and making the corresponding shutter speed

adjustment to keep EV the same. And if you weren't sure of

exposure, you could combine the two types of bracketing.

People have also been known to bracket focus, as well as exposure

settings. All this bracketing can quickly use up your film

budget, running through all available combinations of shutter speed,

aperture, and focus.

[tree]

You can do either: the choice depends on the effect you are looking for. If you are on a tripod and want to keep depth-of-field constant, then change the shutterspeed. If you are concerned about freezing the action but not depth of field, then use the aperture ring.

[craig_bridge]

Unless your camera body has exposure backeting features or an exposure compensation feature, you have to switch out of aperture priority mode if you want to bracket exposure. In aperture priority mode, if you change the aperture, the camera will change the shutter speed so you get the same equivalent exposure. All this does is a DOF bracket. In manual exposure mode, you can bracket exposure with either the aperture or the shutter speed, your choice.

 

If your body has exposure bracketing and/or exposure compensation, staying in aperture priority mode will cause the shutter speed to be changed for bracketing.

[chat_sirichanvimol]

Ok -

This make sense. I have bracketing on one camera and only apeture priority on the other. I'll switch to manual and bracket the exposure while keeping the shutter speed constant.

 

Thanks everyone.

[imaginator]

If your camera can't do manual exposures, then sometimes there are other ways to control this: exposure compensation (+ and - settings) or film speed setting (if the camera has manual control of this) First, let me explain basic manual exposure techniques. With a "stationary" subject (doesn't move) I choose an aperture first (this allows control of the depth of field... what's in focus), then bracket the shuuter speeds. If the subject moves, or if you think the camera might shake too much (this is common with longer focal length lenses when you don't use a tripod) then choose the sutter speed first, then bracket lens apertures. One way to make metering simple si to meter the palm of your hand in the same light the subject is in, then adjust the exposure 1-stop (open aperture or use slower shutter speed) The adjustment is because your hand is brighter than a "gray card" (what camera meters are used to) You could carry around a gray card, but I find it's much easier to use my hand and adjust 1-stop. This is similar to what they call an incident meter (measure the brighness of the light instead of the brightness of the subject...that's what fools camera meters... they can't deal with light or dark, just "middle gray") Don't worry about focussing when metering your hand, just hold it at an angle close to the lens. Take one shot using the camera meter readings, then bracket (shutter speed or lens aperture, or exposure compensation ) so you end up with three exposures: "underexposed", "correct" and "overexposed". I use the quotes because there is no such thing as correct exposure... you either have to make educated choices, depending on the subject, or bracket and learn from your results ( a great way to learn!) This all much more important with slide films... not a big deal with print films, but avoid "underexposing" too much. Does any of this make sense, or have I just confused you even more? Don't worry, it's very easy with some practice. Adjusting the film speed setting is a way to "trick" the camera into changing exposure if there is no other way to control this. Do you have the operating manuals for your cameras, or can you tell us what specific cameras you have?