"Standard" aperture?

[g&m]

Hi everybody, i'm a newbie and i come from the "point and shoot" cameras word, so I used not to worry about aperture, only about shutter speed and ISO.

Now i have a doubt: what is the "standard" aperture to use to get a good shot? I mean, what aperture is considered "average", to have a good focus in my pics?

In other words: when i have to decide what aperture use, for example when i'm shooting a party with my friends, what f value should i use=

tnx

[RecurrentNerve]

Not as simple a question as you might think, because there's no such thing as a standard aperture, and no such thing as 'good focus', really.

If you are shooting indoors and don't want to use the flash, you need as wide an aperture as possible to let plenty of light in the camera. This has the added effect of blurring the background of your shots, as wider aperture=shallower depth of field. This is a good thing. Many beginners think a good shot has to have everything in focus. This is incorrect.

If you're taking a photo of your friends at a party against a backdrop of drunk people you barely know, why emphasise the drunks as much as your friends? Blur them out with a wide aperture. In fact, any portrait or 'people' (or animal) shot should really be taken with a wide aperture. Just make sure the eyes are in sharp focus. The only time you have to watch out is if you have a group shot where people are standing behind other people; here you run the risk of getting the people behind slightly out of focus, so adjust the aperture slightly accordingly.

If you are shooting a landscape shot where you want everything in focus from front to back, then you would go with a smaller aperture like f/11-f/16.

The best thing I can advise is practice, practice and practice.

[wulf]

How about spending some time in aperture priority mode? That means you have full control over the aperture and can explore what works. For example, you might do a little walk round your area and only take shots with your aperture wide open. Do a second circuit with the camera set to a relatively small aperture (eg. f/11), taking the same set of subjects.

Back at base, compare the two. Which ones work better? Why?

Restricting yourself like that is a very good way to develop your understanding.

Wulf

[RichardTaylor]

@g&m

With a P&S almost any aperture gives you lots of DOF (depth of field or zone of sharpness), except for extreme close ups of flowers etc.

Example (1)
(f4 with a P&S)

Camera Canon PowerShot G11
Exposure 0.002 sec (1/500)
Aperture f/4.0
Focal Length 6.1 mm
ISO Speed 200
Exposure Bias -2/3 EV

With an SLR you have a lot more control over achieving your desired results.

When you are shooting a party with your friends; Are you shooting at night with available light, or with a flash gun and if with a flash gun what mode are you shooting in and at what ISO?

In daylight - what is your priority for a "good" shot.
It can be very much scene,lighting and lens dependant,

Example 2
Daylight cityscape.

Camera Canon EOS 5D
Exposure 0.005 sec (1/200)
Aperture f/13.0
Focal Length 24 mm
ISO Speed 100
Exposure Bias -2/3 EV

Example (3)
or a dreamy flower pic.

Camera Canon EOS 40D
Exposure 0.001 sec (1/1250)
Aperture f/2.0
Focal Length 135 mm
ISO Speed 100
Exposure Bias 0 EV
Flash Off, Did not fire

Example 4
Or do you want to remove a "messy" background, like cityt buildings?

Camera Canon EOS 40D
Exposure 0.001 sec (1/1000)
Aperture f/2.0
Focal Length 135 mm
ISO Speed 400
Exposure Bias 0 EV

Have a look at this 5 part tutorial, on this suite , of what it is all about when you can control exposure.

This is part 1 and there are links to the parts in the tute.
Exposure (1) A balancing act.

[g&m]

thanks to everybody for your clear and rich explanations!!

[jdepould]

A lot of the people I hang out with [jokingly] toss around the phrase "f/8 and be there."

I call f/5.6 and f/8 "who cares?" apertures. It's what I use when I'm not terribly concerned with depth of field, and I've got good light.

That's not to say that I use those apertures more often than others--I don't. More often than not I'm shooting wide open (f/2.8 for my gear). Partly because I'm constantly shooting in bad (or nonexistent) light, and partly because I'm trying to isolate my subject from other elements in the frame.

Sometimes I don't want that isolation, so I'll stop down to get more depth and more background.

Like any other setting, it's a process of evaluating my priorities for a given shot, and making the necessary compromises to get the desired result.

Hope this helps?