Aperture - What does it do?

The generation of today knows ISO as a button...the older generation remembers how difficult it was to constantly change the camera spool whether you were inside our outside. Basically now it is a setting controlled on your camera, that allows you to adjust the sensitivity of your cameras sensor, this sensitivity is the sensitivity to light. In the old days, you could purchase spools with different ISO’s. Now we do it digitally...spoilt right! ISO is shown as a number on your camera settings. Eg: 100, 200, 600, 800 etc. The value to which you can set the ISO number is determined by your camera. Eg. Some cameras can go to higher ISO’s than others. A high ISO is 6400 (this would give you a noisey/grainy image, the effect your cell phone gives when you take a photo at night) A low ISO is 100 (this would give you a clean crisp image) So what does ISO do INSIDE your camera? The lower your ISO, the less sensitive your sensor will be to light and therefore the less grainy your image. Eg: ISO 100 The higher your ISO, the more sensitive your sensor will be to light, and therefore the more grainy your image will be. Eg: ISO 1600 or 3200 etc. If you are taking photos outside and there is sufficient light, keep your ISO as low as possible, ie. ISO 100 or 200 to avoid grain on your images...your shutter speed and aperture should be adjusted accordingly to give you a perfect exposure. And if you are taking photos inside or outside and its become dark, lift your ISO accordingly (keep in mind your shutter and aperture). A good rule of thumb is to never go above ISO 800. Even a modern day DSLR like a D810 or 5Dmk3 still gets a little grainy above ISO 800, and if you fussy like me, rather add a little flash to keep the image crisp. Yes...you can remove Noise in post production, Lightroom or Photoshop...BUT...yes there is always a but, it will never be the same. The software smooths the noise out, making the image a little more 'blurry' kinda like rubbing all the grain with your finger to make it smoother. Its visually better but its not as sharp. So here is an example, and yes the 2nd image IS taken with flash, but the explanation and results would be the same. This was taken with natural light as the sun had just dipped over the hill. ISO 400 shot at f4 - now although this is clear and pretty sharp. This was taken with off camera flash. ISO 125 shot at f4 - if you look closely you can see that the clarity of the image looks less disturbed like the eye in the above picture. Now imagine the difference between ISO 100 and ISO 3400.

Understanding how your shutter actually works, makes photography so much easier! Most people assume the obvious, fast shutter = sport! Thats not entirely true throughout photography, but lets take a look. What is Shutter Speed? Shutter speed is a setting controlled on your camera, that allows you to adjust the time that the shutter “door/curtain” opens for, to expose the sensor in your camera. Shutter is measured by Shutter Speed which is measured in seconds. Eg: 1/250sec, 1/30sec, 1/3200sec and so forth The value to which you can set the shutter speed is determined by your camera. Some cameras go higher than others, but generally all your shooting is done in the standard range. A fast shutter speed is 1/3200 A slow shutter speed is 1/10 1/1 = 1 second, 1/2 = half a second, 1/100 = 1 hundredth of a second...you get the picture :) Now how does it physically work? This will make your brain understand the above much better. Here is a quick little video on how your shutter actually works. Its that basic, the mirror moves up, the first door opens, exposing your sensor to the light/picture through the lens, it then closes after the set amount of time. This is why if you leave it open too long (after shooting indoors) your picture is blown out and white when you walk outside with the same setting. (you would need to adjust your ISO and Shutter accordinly) So...the faster the shutter speed (ie the higher the shutter number) the less light the camera will let in onto the sensor. A fast shutter will freeze objects in motion. The slower the shutter speed (ie the lower the shutter number) the more light the camera will let in onto the sensor. A slow shutter will blur objects in motion. Therefore to capture/freeze something in motion, you must use a high shutter speed. (ie. insure good light conditions) To let more light in, a slower shutter speed is needed. (ie. this is good for poor lit conditions) Remember, a fast shutter will always provide a much sharper image. As a rule of thumb, never shoot under 1/150 or 1/100 unless you have an extremely steady hand. However , if you are using a longer lens, and shooting above 120mm try to make sure your shutter speed is 1/400 and up to ensure pin sharp images. Here is a classic example of a fast shutter speed taken mid day with more than enough light. This is a great example of a slow shutter speed taken with a little bit of flash to create some form of movement on the dance floor at a wedding. If you have any questions, drop them in the comments below...I'd love to help.

Let us know what basic camera settings you struggle with and we try and include it through our coverage of basic camera settings. Drop us a comment below what you struggle with the most?