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um, like whats an ISO?
Charlie Brown
Registered Users Posts: 199 Major grins
hey can we get an explanation of ISO, F stops, speed settings and their effects on how the picture comes out? im dumb when it comes to this stuff so if you could dumb down your explainations for me id appreciate it.
charlie
charlie
I can only hope to progress to the point of one day being a second rate photographer, wish me luck.
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charlie
for f/stops, exposure, iso, and more, read this thread in the hall of wisdom
iso is simply a measure of how sensitive the sensor is to light. it can be throttled from 100 (on most cams) to 1600 (on most cams). some have lower isos (kodak slr has iso 6!) and some have higher (canons can go to 3200). iso 100 (least sensitive to light) -->iso 200, you've m ade the sensor 2x more sensitive to the light. and so on.
bright day, outdoors, you shoot iso 100, b/c there is plenty of light. at night, in dimly lit cathedral, you shoot at 1600, because you need to make the sensor as sensitive to light as possible.
now, go read that thread and come back with your questions. we're here to help.
capisce?
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You can find alot of info here----> http://luminous-landscape.com/ go to the drop down menu for the Understanding Series.
Also there is alot of info here----> http://www.dpreview.com/learn/
Hope that gives you some reading material.
Tim
Speak with sweet words, for you never know when you may have to eat them....
not for nothin' but there's plenty of great info right here on dgrin. try here first!
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ISO is basically how sensitive the sensor is to light. Low ISO (i.e. ISO 100) is like when you have been outside in the sun and can look at pretty bright things without trouble. But you go inside real quick and everything looks super dark.
High ISO (i.e. ISO 1600) is like when you have been in the dark for a while and you can see very dim things, but shine a light in the eyes and you go blind. High ISO makes the cameras sensor more sensitive to light.
F-stops or aperture is basically like squinting. It controls how big the opening is that allows light into the sensor. The wider the opening, the more light can get in. The more you squint, the brighter the environment you can comfortably view. Another way of looking at it is the pupil of the eye. When the pupil is dilated you can see things in low light. The pupil (or aperture) when constricted allows you to view bright environments.
Shutter speed is like blinking. The longer you keep your eyes open, the more light hits your eyes. Keep your eyes closed and just take a quick blink look at something bright and it probably wont hurt. You are adjusting the shutter speed of your eyes to control the amount of light that you let in.
All three of these exposure variables can be interchanged with each other. If you are in a bright environment you can make the sensor less sensitive to light by lowering the ISO, you can also use a small aperture to limit the amount of light, and use a short shutter speed.
If you want to shoot in a dim setting, you can open the aperture, crank up the ISO, and use a longer shutter speed. How much of each variable you use depends on how you want the photo to look.
High ISO typically shows more grain, low ISO has less
Small apertures have a wider DOF and star patterns on point sources of light
Wide apertures have a shallow DOF and turn point sources into spheres
Fast shutter speeds freeze movement and action
Slow shutter speeds blur movement and action
So depending on your artistic needs, you would choose settings that appeal to you. All three variables also need to be balanced so that the resulting exposure is not underexposed or overexposed.
A good study project is to read this page, and with time and practice, understand it:
http://www.fredparker.com/ultexp1.htm
"Failure is feedback. And feedback is the breakfast of champions." - fortune cookie
Tim
Speak with sweet words, for you never know when you may have to eat them....
moderator of: The Flea Market [ guidelines ]
H: At first J was gonna start out by posting a thread asking for your own (and everyone else's) assistance, but then I persuaded him ( :beatwax ) to read through a few of the existing posts first. And yours was the first we stumbled across.
J (:hurt ): Right. Who could ignore that plaintive call from out of the darkness?
H: As some very knowledgeable folks have already alluded to (two of my own heroes included), there is a heck of a lot of technology that goes into making today's digital photography happen. As you can see from the links provided, there can be some rather lengthy discussion of it all. HeHe.
J: However, with camera in hand, photography really becomes very simple (at least my own version). Shot to shot, day in and day out, there are only three major technical decisions I make, and I think you guessed them.
F-stop
Shutter Speed
and ISO
H: Here's my process (for general shooting, I almost always use Aperture Priority mode):
Step1: Adjust the aperture to blur or sharpen the background to your liking. With the S50 it's easy, 'cuz you have the live preview showing on the display (what you see is what you get). End of step 1.
Step 2: Check the shutter speed to make sure that it's fast enough so that you won't get a blurry shot (trial and error will show you how slow you can reliably go with that camera). End of step 2.
Step 3: If the shutter speed readout is too slow, then bump up the ISO until you can be reasonably sure you'll get a steady shot. End of step 3.
That's it in a nutshell.
J: Now I can go into an explanation of some of the other finer points involved (white balance, exposure compensation, AF mode, etc) ad infinitum...
However at this stage, if you keep the technical side simple and focus your energies on composition, angle, focus, timing, and lighting, then I think you'll start to get the knack of making a technically good photograph, great.
H: So go out and have a good time shooting, and think about the camera as little as possible.
J&H
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