Aperature/Shutter Speed

[Nighthawk07]

Okay so I understand how these both work and how smaller aperature=slower shutter to allow more light in for exposure. But I've been messing around taking pictures and I just can't figure out what aperature I should use. Do I wanna generally use the largest aperature possible for the situation? or the smallest? I really don't know when to use a small or large aperature.

[Izzy]

What kind of DOF do you want? How much light is available?

If you want a blurry background, the lowest possible aperture would be best. If you want things more in focus, raise the aperture.

Jesh, stop lurking.

[JeShUa]

Sometimes too small of a number will cause too small of a depth of field. It really depends on the shot.



Taken at F/1.4

[Izzy]

^ f32 FTMFW.

Actually, no, you'll start seeing dust specs if you're cameras dirty at that tiny aperture.

[kelmar]

As stated above, something like a f1.4 will give you a very shallow depth of field making only a small plane of the picture in focus. Something like Ansel Adams is shot with an f64 making a ton of the information in focus. However, something like an F64 will also compress a lot more information making it appear like there is LESS depth to the image.

Regardless, changing your aperture also changes your shutter speed; and it's all directly tied to your ISO as well. Ideally you should be keeping all of these into perspective when shooting.

Good luck!

[kelmar]

Depth of Field

[arisenfury]

Lucky for you I just did a speech on digital photography in my Communications class and I have some pictures from my powerpoint.

Pretty much you'll just have to play around with your lens and find out which aperture works best on it. Every lens has it's sweet spot, usually it's somewhere in the middle. With fast primes like a 50mm f/1.8 or 1.4 you'll need to stop them down to ~f/5.6 to get some amazingly sharp pics. Some lenses are designed to perform the best at their biggest aperture (lowest number), these are usually f/2.8 lenses.

Also factor in how much light is available to you and how you'll have to adjust your shutter speed, too low of an aperture (higher number) you'll have to worry about camera shake by extending the exposure.

However as stated with the different apertures you get different depths of field. Here's an example of one extreme to the other.

f/2.8:


f/22:


Another fun thing about the different apertures is how they effect light sources in a picture. Lower apertures (higher number) can give "sparkle"-like effects. These were pretty far in the distance so not as effective, but look at the blue on the extreme left for a good example.

f/22:

[sb12007]

What are you photographing? Macro or Wide angle. That should tell you what DOF you want.

[Nighthawk07]

Thanks guys (arisenfury, I'd rep if I could!).

I'm just using the kit lens on a rebel xt by the way. I just out today in my backyard messing around taking pictures experimenting with different aperatures.

[arisenfury]

Originally Posted by Nighthawk07

I just out today in my backyard messing around taking pictures experimenting with different aperatures.

That's the way to do it .

[GeezerSi]

Originally Posted by Nighthawk07

Thanks guys (arisenfury, I'd rep if I could!).

I'm just using the kit lens on a rebel xt by the way. I just out today in my backyard messing around taking pictures experimenting with different aperatures.

apertures

[Nighthawk07]

Originally Posted by GeezerSi

apertures

lol, thanks.

[OweNsi]

i want a rebel xti