So let's talk about the most common settings you'll find in modern digital cameras. From the simplest to the more complex, ISO.
ISO stands for International Organization for Standardization. I know, I know, it should be IOS, but who am I to tell them otherwise?
ISO sets the standard for pretty much everything we use or do such as the ISO9000 for quality management in companies.
In terms of photography. ISO stands for a film's sensitivity to light. We used to call ISO as ASA. So you might hear some older people refer to it as ASA. But now it's generally referred to ISO.
In my time, we used to use film in cameras. You know, those things you buy in boxes that comes in canisters that you have to put into the camera carefully or you might expose it. Then have to wait a few days to see the result of your pictures? No? I guess I'm too old for you people.
You see, back in the day, we had none of these fancy smancy digicams you have were you immediately see the result of your shots. Where you can just print it right away from your printer or just upload it to your computer. We used to do it the hard way.
But even with new technology, taking photos still has to adhere to the timeless law of physics. Basically, ISO settings adjust your camera sensor's sensitivity to light same as film.
ISO is basically used like this. Think of it as a light with a dimmer switch. The darker it is, the higher you set the switch. So in very bright light, set ISO to the lowest number such as 50 or 100. The darker it is, set the switch to a higher number like 400 and up. Easy right?
Not so fast, in the old days (when we used film), the higher the ISO rating such as 400 or higher, the grainier the picture. Why is that? Because film uses silver halide granules to capture light. The bigger the silver grains, the more sensitive to light. Meaning, it can capture images better in lower light.
The problem though is that when you develop the film, there's a lot of grain in the picture, so it looks noisy or like a photo from a newspaper.
The lower ISO film has finer grains but it needs more light to capture a proper image. Hence, they are used more for outdoor with good light or indoor with good flash. More like what you see in magazine covers.
So how does this relate to digital cameras? Well, digital cameras also has grains when you set a higher ISO. When a digital camera sensor is set at a higher ISO, it gets something called signal noise. Basically, kind of like the noise you get on your phone or speaker when you put your cellphone near them. Instead of grain, these are interpreted as "image noise".
The best digital cameras are able to get a high ISO such as 800 or 1600 with little or no noise. The lower end cameras can show noise at 400.
When you take a picture, check the light around you to see if your ISO setting is good enough. Generally, the brighter the light like day light from 7am to around 4 to 6pm in the summer, you can usually use ISO 100. When you get to indoor or when you're shooting dawn, dusk or night time. Use ISO 200 and up.
With this general rule of thumb, you'd think that will solve all your problem. But wait, when your picture turns our blurry, sometimes it's not the focus that's the problem, it's choosing the wrong ISO. Either too high or too low.
I'll talk about how to choose the right ISO on my next article.
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