Lightening your image

[flibbit]

So when you have a subject you're wanting to snap a picture of but it's in less-than-ideal light, what is the first thing you do? Increase ISO? Reduce shutter speed? Increase the aperture?

Since all three can generally increase your camera's sensitivity to light or the amount of light allowed in, what do you alter first and foremost? I realize that it's probably not as simple as this and that ISO/shutter speed/f#s should complement each other in a given setting, but for someone who is a beginner with the technical side of photography, how do I start simply?

I've played around with each setting and have a generally good idea what ranges do what. But do you tend to preference changing one setting over another in order to lighten your image? I'm guessing unless you're consistently using a tripod, changing shutter speed isn't your first choice.

 

[480sparky]

Choose a shutter speed and aperture that suits the subject, then adjust the ISO to maintain them.

 

[MLeeK]

You have to prioritize.
You have to use a shutter speed that is appropriate for your subject and for you to hand hold the lens. You can fix a lot in post, but you can't fix blurry.
You have to use an aperture appropriate for the DOF you have to have-or the widest aperture your lens allows for. Again, you can't fix blurry. You gotta have what you gotta have.
Once you get to the point you can't do anything but raise your ISO. You can remove noise in ISO-you can't fix blurry.
When you are raising your ISO it's imperative that you not underexpose!!!! DO NOT think "Well, if I get fair exposure at this lower ISO, I can boost in post processing..." NO!!! If you boost exposure in post processing it will make the noise infinitely worse than it would have been if you had used the higher ISO to begin with!!! If anything you want to go a little to the +. Reducing exposure will hide some of the noise, but you never want to have to raise exposure.

 

[KmH]

I always consider the ISO setting first, based on the amount of light I have to work with.

Second I set the shutter speed to make sure I will be stopping whatever motion is in the scene, if any.

Choice #3 is the lens aperture relative to the depth-of-field I want the shot to have.

The truth is I actually consider all those things at essentially the same time, but I've been doing that for 30 years. Since my cameras had separate adjustment wheels for the lens aperture and shutter speed I often changed both at the same time.

 

[MLeeK]

I always consider the ISO setting first, based on the amount of light I have to work with.

Second I set the shutter speed to make sure I will be stopping whatever motion is in the scene, if any.

Choice #3 is the lens aperture relative to the depth-of-field I want the shot to have.

The truth is I actually consider all those things at essentially the same time, but I've been doing that for 30 years. Since my cameras had separate adjustment wheels for the lens aperture and shutter speed I often changed both at the same time.

BUT! You have to add that you can probably look at your scene and know what you are going to need in your settings! I am willing to venture a guess that you can almost always hit within about 1/3 stop or so exactly what you need by just looking around you.

 

[scorpion_tyr]

Yes, you have to prioritize. This is my method: I think about quality, freezing/showing motion, and depth of field (DOF). I pick which one of those is most important, somewhat important, and what doesn't really matter. Then I use that to figure out my settings by 1) What I need to use 2) What I want to use and 3) What I have to use

Say if I'm trying to get some sports shots where my main priority is freezing the motion, my second is the quality, and I'm not too concerned with DOF. Then I set the shutter speed where I need it. Let's say 1/1000th. Then I set the ISO where I want it, let's say 200. And then based on those two settings I'll adjust my aperture to where I have to. Depending on lighting I may have to play with the last two (ISO and aperture) up and down if I max out my aperture and still getting under exposed.

What if I'm doing some head shots for an important client to use in advertising. Quality is my first priority, DOF is my second since I want the outside background blurred out and not distracting, and since my subject is staying still and I have a tripod shutter speed is the least important. Now I set ISO 100 (What I need), aperture to f/2.8 (What I want), and shutter speed to 1/250 (What I have to).

Now let's say I'm shooting some real close up macro shots. I need to get the deepest DOF possible since it'll be shallow anyways, I want the highest quality possible, and since I'm using a tripod and subject is still motion isn't a factor. So I'll set my aperture to f/18 (What I need), my ISO to 200 (What I want) and my shutter speed to 1 second (What I have to)

Each situation is completely different, but often times you'll find that ISO is your middle priority (since you always want high quality) and either shutter speed or aperture will be your first priority, or your third.

Where it really gets fun is when you find out you have to re-prioritize because you've hit the limits of your gear and other things such as focal length, camera shake, ambient lighting, x-sync factor, flash not reaching far enough, etc start to have negative impacts on your image.

 

[flibbit]

Thanks for the info so far, everyone. I'm sure this will get easier the more I use my gear. For now, its new enough to me it's not intuitive but an issue of remembering what settings tend to be best for a given situation. It helps to read different approaches too.

 

[KmH]

A key is to do it in the same order every time. You also have to consider your metering mode, white balance, focus mode, and focus area mode too.

 

[TheBiles]

I consider shutter speed first because I'm not going to get any shot if it's too long. Then aperture if I need DoF, otherwise I go wide open. I let ISO set itself without fear because the 5D can manhandle any ISO I would typically encounter (otherwise I'd have a flash with me).

Sent from my Nexus 7

 

[Big Mike]

In my DSLR class, I tell the students this...

"If you forget everything else in this class, remember this...
#1. Set an artistic goal. (setting your artistic goal, will tell you which of the three settings is most important, and thus which to change)
#2. Get to proper exposure."

So in other words, before you think about making the photo brighter or darker etc. thing about what your artistic goal is. Do you want a shallow DOF, or deep? Do you want to freeze motion or show some blur if something is moving? So you want less or more digital noise?