[NT73]

I know a lot, but not everything. So in simple (ish) terms what is Bracketing and what does it achieve.
And I hope I am in the right forum. :/

[Rufus]

Well NT, fortunately for you, I know everything about everything, ever.
So, here we are then.....
Bracketting is simply the use of over and under control, in a logical way.
For example:
Exposre bracketting may be shooting a "correct" exposue, 1 stop over and 1 stop under.
Shutter speed bracketting could be used in the same way.
Flash exposure bracketting......Same.

It allows variation for creativity, or avoiding errors.
With digital, especially RAW shooting, it's less critical, but an accurate exposure in the first instence, is better than an adjusted one afterward.....

Does that make sense?

Any control used at a variety of settings to achieve an effect is essentally bracketted.

HTH

[muzza]

What Rufus said!
Now, in simple terms when you press the shutter button the camera takes three shots. One correctly exposed, one under exposed and one over exposed. On most cameras you can set the bracketing amount.

Say for instance you set the amount to 1/3 of a stop you will get an image exposed correctly, an image under exposed by 1/3 and an image over exposed by 1/3

Hope that helps!

[NT73]

What Rufus said!
Now, in simple terms when you press the shutter button the camera takes three shots. One correctly exposed, one under exposed and one over exposed. On most cameras you can set the bracketing amount.

Say for instance you set the amount to 1/3 of a stop you will get an image exposed correctly, an image under exposed by 1/3 and an image over exposed by 1/3

Hope that helps!

That is beautifully put muzza. and that explains exactly to me what it does.
Rufus was a bit technical, but thanks anyway. I get what he is talking about now.

Does that mean then that if I bracket the exposure by 1 stop, I will get three photo's on my card, or camera. as opposed to one, if I didn't use bracketing.

[NT73]

Addendum to that...
I suppose the camera takes one photo and the software creates the other two, yes?

[Polly]

Does that mean then that if I bracket the exposure by 1 stop, I will get three photo's on my card, or camera. as opposed to one, if I didn't use bracketing.

That's it exactly - you get 3 photos on the card.

If you're shooting jpg, rather than raw, it enables you to use the 3 shots eg for layering them in software - then you can maybe erase the sky off one layer and the land off the another layer. That enables you to blend the layers so that the final image has, in essence, two exposures.

It can be a neat way to correct a burned out sky as the underexposed shot would probably give you more sky detail .. if you follow my drift.


Pol

[Zig]

Also handy for that awshucks occasion when you want to capture high dynamic range(ie, grabbing highlights and shadow detail).

[Zig]

As a technique, I also find it handy for putting up shelves.

[Toad]

Rufus makes a good point in that bracketing isn't that much value if you shoot RAW. You can do all of the adjustments to exposures afterwards if required. In fact you can blend multiple copies of exactly the same photo exposed differently together (as Polly and Zig suggest). Some cameras have an auto bracketing feature that automatically takes the 3-5 shots at different exposures - but they are not always identical if the shot is hand-held. You may have moved slightly between exposures. Blending multiple copies of the same RAW photo eliminates this potential problem. You also get only one shot on your memory card this way.

The exception is in the case of photos that have the potential of blown highlights - very bright spots. You may not be able to recapture the detail of the highlight afterwards from a RAW photo, and in this case you may want to make a separate shot exposed correctly for the highlight - it is straightforward to lighten a photo without washing it out (make a new layer and set blend mode of that layer to screen - repeat as necessary), but you can't always recapture lost detail from a blown highlight.

[NT73]

Well NT, fortunately for you, I know everything about everything, ever.

So can you play 'Air on a G string', on a D string? Or are you just playing second fiddle.


With the other posts, I have got it figured out now.
Thanks everybody, soon I will be able to put it to use.

NT73.

[Polly]

With the other posts, I have got it figured out now.
Thanks everybody, soon I will be able to put it to use.

NT73.

Possibly - but only if he knows where to shove his Capo

>

>

....assuming Poppy the puppy hasn't chewed it and buried it.


Pol

[Rufus]

I can play HAIR on a bottom "E" string, if that's any help.

I can also play the fool, expertly.

[Rufus]

...........only if he knows where to shove his Capo

:o

Young Pol! This is a family forum> Dont be so rude, you rude thing, you!

[NT73]

...........only if he knows where to shove his Capo

:o

Young Pol! This is a family forum> Dont be so rude, you rude thing, you!

Only used one once, and got my fingers trapped under it, near F#.
She's full of it today. Must be the new software.

[matthew]

Addendum to that...
I suppose the camera takes one photo and the software creates the other two, yes?

I see all the clever people missed this one... so I'll answer, instead.

For the most part, no, each image is taken separately by the camera, creating three (or more) individual photos. The only exception that I know of is that some cameras can do a white balance bracket, which applies a software correction to one single frame to create three distinct images.

One other thought, which nobody asked me for, is that if you're shooting an exposure-bracketed series with an eye to blending them later, use aperture-priority mode. If you use shutter-priority, then it will change the aperture to create the different exposures, and each image will have a different depth of field. The varying amounts of OOF blur will change the size of OOF objects, making them hard to merge.

[slejhamer]

One correctly exposed, one under exposed and one over exposed.

It could be one correctly exposed and two underexposed.

Or one correctly exposed and two overexposed.

Or none correctly exposed.

The initial exposure is still subject to user error and/or camera meter error. The other exposures may or may not overcome such problems.

Bracketing increases the odds of getting a correct exposure, but it can't ensure it.


P.S. What is correct exposure anyway?

[slejhamer]

One other thought, which nobody asked me for, is that if you're shooting an exposure-bracketed series with an eye to blending them later, use aperture-priority mode. If you use shutter-priority, then it will change the aperture to create the different exposures, and each image will have a different depth of field. The varying amounts of OOF blur will change the size of OOF objects, making them hard to merge.

Good point. And it would apply even if you don't intend to merge them, but still want control over DOF.

[Toad]

P.S. What is correct exposure anyway?

It is what the camera says is the proper exposure - except when it isn't...

I suppose the accurate answer is when the camera exposes all parts of the photograph the way you imagined it should before you took the shot. That is called DWIW metering....Do What I Want.

[Zig]

Blimey Toad, I've been searching for that button for yonks!

[matthew]

P.S. What is correct exposure anyway?

It's one that doesn't get you flamed by the masses on PhotoSIG.com.
(They can be a few elements short of a lens, if you know what I mean.)

[NT73]

Matthew ==== I take it then, if you wish to merge bracketted shots while using a-p or s-p, you should shoot on a tripod, and if not shoot on a tripod anyway to take account of camera movement between shots.

How fast does the camera take three bracketted photo's say 1/100th at f 8 as a guideline? I'm thinking in terms of a 350d here.

[matthew]

If you're going to merge shots, a tripod is vital. (They're useful always.) Any movement at all will greatly complicate blending the different exposures.

But, as others have said, there's less need to bracket if you can shoot in raw.



This sunrise was taken from a single image using raw capture, f16 @ 1/8s. The sky was processed at -1.5EV, the ocean at -.5EV, and the foreground at +1.5EV, and the layers were merged using layer masks. Because it was one single exposure, I just braced the camera against a railing. If I was using the exposure bracket - and my camera can bracket up to 5EV, far more than the range I used - it wouldn't have worked without a tripod as the camera would certainly have shifted while I was pressing the button.

(And, feeling sorry for myself, I'd like to add that I took that photo three days ago while I was still on vacation.)

As for the technical details on the 350D, it would probably be taken at the standard burst rate for your camera, which is three frames in one second. Others here with direct experience might be able to correct me.

[shuttertalk]

Wow, great photo matthew!

In addition to the RAW thing - I suppose digital cameras also give you instant feedback, so you can roughly tell whether an image is properly exposed straight away. In the film days they had to wait to get their prints/slides back to see the results, and thus you always used to hear lots of advice of "bracket bracket bracket!" being offered...

These days it's hardly necessary, unless you're shooting an important shot or in a challenging lighting situation...

[Zig]

Nice to see your work again Matthew!
Putting 2 and 2 together here, and as per matthew's excellent example:
By bracketing and combining the shots, you are effectively doing the work that would otherwise have to be done by a combination of spotmetering and a selection of neutral grads: see how the sky is "held back"(in filmy terms) or highlights compressed(in digispeak) whilst retaining shadow detail.
I applaud the digi domain in this respect: no more rattling around for NGs whilst the sunset(or sunrise) slips away!
And, I humbly bear witness: Rufus most definitely DOES know everything, about everything: annoying but true!