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>Ok, ISO has to be a term relative to digital photo taking. >Right? I'm not familiar with it. Help!
ISO comes from the days of film. Whenever I went steppin' with my P&S, I considered where I was going. If it was broad summer and I was at the beach, I'd ask for a roll of ISO 100. If I was back home in the Netherlands, and/or it was winter, and/or I was going to be in some kind of theater, I'd ask for ISO 400. If I had no idea, or if I was going to be going back and forth w/ the same roll of film, I'd compromise and ask for ISO 200.
I had absolutely no idea what any of these numbers meant, mind. I just learned from asking the guy at the kiosk which kind of film to buy depending on where I was going to be.
It turns out (I know now, from reading photo books) that film with high ISO (400 or above) is more sensitive to light, so you can take pictures in dim light and still have the image show up on the film. BUT, the down-side is that high ISO film produces grainy pictures.
The miracle-feature of digital cameras is that you aren't stuck with a given ISO level for a whole roll of film. You can have ISO 200 for one picture, ISO 800 for the next, and then go out into broad daylight and change to ISO 100. Good stuff, eh?
That's because ISO isn't set on the "film" (there isn't any); rather, ISO is set in the camera.
Most beginners just leave the ISO function set to "automatic" for a while, and let the camera pick the ISO it needs to make the exposure. If you alrady know how to pick the ISO needed for different situations, though, you can leave the ISO setting on manual, and change it to your liking. (That also means that you can experiment as you shoot; if the pix are coming out too dark, you simply set the ISO level higher, take a few pix, check the monitor to see if your pix are coming out, and set it even higher if necessary.
High ISO film produced grain. High ISO digital cameras produce "noise." Looks similar to grain, has a similar effect on your pictures (they look kind of "dirty"), you don't want it.
"Post-processing" is the process of getting your pix to the printer (be that you yourself or a photo lab). With film, it was called "developing" the film. I never touched the film. The photo lab developed it.
With digital, the camera develops the film. The difference between older digital bodies and newer ones is, among other things, the sophistication of the software the camera uses to "develop" the images. Newer model = better camera software.
If you're brand new, you set your camera to auto-everything at first, take the pictures, take the "developed" memory card out of the camera and hand it to the photo lab (or your printer) and print the pictures. As that becomes easier, you learn to take the "developed" memory card, put it into your computer, and check the camera's work. The pictures are already "developed," but you get to look over the work and make "fixes" when you think the camera did a bad job. This is called "post-processing." You can do seriously simple things, such as crop, which edits out parts of the picture you don't want, such as all the area around a horse if you took the picture with a not-quite-long-enough telephoto lens ... you crop the picture so that all the grass and grandstands and officials standing on the sidelines are gone and the entire picture is filled with just the horse, as though you'd had a much more powerful telephoto lens in the first place.
If the photo is too dark, you can make it lighter; too light and you can make it darker; etc. etc.
And one of the things you can do is reduce the "noise," so that the picture looks "cleaner," like it would have had you not been shooting at a high ISO level.
Point of this post is that the D80, like almost all reasonably priced digital cameras older than a year or so, has software which isn't very good at processing the pictures if there's a high level of noise. So if you want low noise, you have to have a faster lens, a more expensive camera, or learn to use computer software to clean up the noise.
Hope that all makes sense!
-- LaDonna
PS: One of the best things I did before I bought my camera is to buy the digital photography book to go with it. I highly recommend you consider doing the same! That's because not only will all these issues become much clearer to you, but also because most books on digital photography actually spend the entire first part on helping you choose your camera. The book will raise issues you didn't even know you had! And it will make it all that much more fun when you finally get the thing in your hands. It might be a week, or even a couple months, before you have your camera. But depending on where you live, you could have a seriously good book on digital photography for beginners in your hands tonight!
_________________________________ A little knowledge is a dangerous thing
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