Exposure Discipline-Bracketing

[drg]

Exposure control is fundamentally important to producing the quality piece of film needed to make a good print. A disciplined approach to getting that shot includes regular use of exposure bracketing.

Trick negative films benefit just as much as do slide emulsions. High speed film, IR, pushed film, etc. all can have anomalies that may need a slight bit of help. If your camera doesn't automatically support exposure brackets, the best way to start is to just shift your shutter speed up and down one increment from the optimum 'proper' exposure at the Aperture of your choice.

You can shift both up and down to keep everything in a 'range' or just change the Aperture (though this may affect DOF in a less desirable way too) up and down a full or partial stop.

Dark and bright subjects need exposure bias to come out properly and not be incorrectly exposed, but they sometimes need a lot more than one always realizes.

Older film will sometimes change its response curve if exposed to heat and may need some bracketing to get the best thickness of negative (or positive).

The following examples show a view of what you are trying to accomplish. The b/w (which are really in color!) images on the single strip are of extremely high contrast snow shot on high speed film with the ISO set for half the rated value. 800 instead of 1600. There is a 1-2/3 +/- stop per frame. This is in addition to a full stop adjustment for the fact it is snow. The film was scanned as a filmstrip on a forensic scanner so that all the frames were using the same values for visual presentation.

The slides are from a test roll from a commercial shoot. The base exposure is optimum and you can see on the darker flower that the 'proper' exposure makes the flower to dark.The EV indicate base, + and - increases of the exposure value. EV is a little different that stops.

[Greg McCary]

Funny you should bring this up. Most often I bracket wit the shutter and most older camera instructions suggest changing the aperature.

[Xia_Ke]

Good post drg I always bracket my shots. It's part of routine to always do +/-1 stop bracketing. If I think I've got a shot that is really a winner, I will even do a +/-2 along with the +/-1 just to be on the safe side which never hurts since my main camera is over 50 years old. Bracketing as a rule of thumb has actually been driven home even more so now that I'm working in the darkroom. It's not that much of a deal to correct in the computer but, it is a big change for when trying to wet print.

[jgredline]

More to learn.... ;-)

[Xia_Ke]

More to learn.... ;-)

Not necessarily. Think of it like digital. When you shoot digital, I bet you check images and/or histograms on your camera to see how they are coming out. Well, will film you can't check. Bracketing is kind of how you check, or more properly help to assure you have proper exposure.

[jgredline]

Xia, I understand, but how do you check exposer on a film camera? Perhaps I should get me a light meter as well.

[Xia_Ke]

You just need to get used to your combo of film/camera/meter/development. After a couple rolls you will start to see that maybe your exposure is off a little here or there and I just make mental notes of little adjustments to make for future shooting. I also keep records of all my developing. So say I'm shooting in a certain lighting situation and I notice there turns out to be too much or too little contrast, when shooting in similar scenes in the future, I will adjust my developing to compensate. Of course, this comes into play when you're doing your own developing. I know it sounds like Greek right now but, after doing a couple rolls you will see.

[jgredline]

You just need to get used to your combo of film/camera/meter/development. After a couple rolls you will start to see that maybe your exposure is off a little here or there and I just make mental notes of little adjustments to make for future shooting. I also keep records of all my developing. So say I'm shooting in a certain lighting situation and I notice there turns out to be too much or too little contrast, when shooting in similar scenes in the future, I will adjust my developing to compensate. Of course, this comes into play when you're doing your own developing. I know it sounds like Greek right now but, after doing a couple rolls you will see.

Thanks Xia, this I do understand.. I have already started with the mental notes.