How to Master ISO in Digital Photography as a Profession

Have you ever noticed photos, which contain one clear object, and others will be blurring? These kinds of images are really cool if you catch someone who is moving in high speed. You will feel that you can stop time to catch them. Moreover, you can move as fast as them freely. The blur environment will show you how fast you can achieve. Actually, these images use ISO settings among digital cameras. Though ISO is just a small part in photography, you cannot ignore ISOs by valuing it into something to catch high-speed movements. Actually, there are many tips and rules you need to learn to take a photo with correct ISO number like a Pro.

If you search ISO directly on Google, you will get numerous ISO definitions. The International Organization for Standardization is the frequently answer to ISO. It is the official group to develop ad publish international standards. In some degree, ISO settings in digital cameras are also similar with ISO standards. ISO is the standard to measure the light sensitive in film photography. Moreover, Camera ISO, Aperture and Shutter Speed are the three aspects every photographer should know before taking photos with digital SLR equipment.


Part 1: What does ISO mean in digital photography

The first thing you should know is that, the higher ISO setting is, the more blur photos you will get. ISO is the measure of image sensor, which is similar with film photography. You can adjust image sensor to catch high-speed objects. For example, if you want to shoot running animals in the plain, you need to set high ISO number. As a result, your photography will not as clear as images in low ISO setting. In addition, high ISO mount will cause in noise and film grain. As for low image ISO number, you can get higher image quality than high ISOs. Or you can also regard ISO values as standards to test photo quality, low ISO number represents high image resolution. Though every DSLR has its own Basic ISO, and you can use lowest ISO number for daily image shootings.

You should also know some popular ISO numbers. ISO sequence varies form ISO 100, ISO 200, ISO 400, ISO 800, ISO 1600, ISO 3200, ISO 6400 and so on. You may have found the rules between those ISO values. ISO 200 is twice higher sensitive than ISO 100, and ISO 200 is twice faster than ISO 100. The ISO speed of 100 is 1 second. Thus, you can know that ISO 200 is 1/2 second. ISO 400 is 1/4 second compares with ISO 100. Therefore, you can capture the same images with times, which bases on ISO speed.

ISO Adjust

Part 2: Differences between low ISO and high ISO

After reading the above ISO meaning Description, you should have the basic framework of ISO camera settings. However, it is far from enough ISO definition before you can apply ISO value as a Pro. You need to make it clear that the certain ISO number in different situation. Low ISO and high ISO are relatively opposite.

If the surrounding lights are bright, you just need to use low camera ISO, ISO 100 or ISO 200 is enough. The lower ISO setting you insist, the better and clearer images you can get. When you have your camera mounted or use a tripod to support DSLR, you can take creative photos with low ISO sensitivity. Leaving more time to shoot somebody or something with lowest ISO enables you to shoot with translucent photos. Some ghosts are created by this way. Low ISO number is also required if you are taking flowers or something immovable.

While high ISO aims at dark environment, thus, if you take images indoor, you need to improve ISO number a little higher. Actually, many latest digital cameras offer “Auto ISO” feature, which can help you to shoot without enough lights. As higher ISO setting will lead into too much grain, therefore, you have to lower ISO number in a degree.

ISO Camera

Part 3: Important factors to influence ISO settings

How to choose suitable ISO setting is not as easy as it pretend? Though you may adjust ISOs according to light and image quality, there are other ISO influences to consider about. Whether to use tripod or the kind of lights, and moving speed is also necessary. Thus, I list some situations, with which you can copy or follow to use ISOs correctly.

1. If you are watching basketball games indoor, you need to use higher ISO speed. Because the environment is not bright enough, and high ISOs are beneficial to high speed moving objects.

2. You are limited to use flash in somewhere serious. For example, you cannot use flash in concerts and galleries, which may disturb others. Thus, high ISO sensitivity is nice choices.

3. During picnic time or hiking with good sunshine, using ISO 100 or 200 is enough. If the sky is overcast or the time is late, you can apply ISO from 400 to 800 to figure out.

4. For those who prefer to take pictures in dark areas, for examples, you can use high ISOs too if you want to give someone a surprise.

5. Sometimes, you may need to shoot with artificial lights, it is wise to use low ISO setting. For instance, you are surrounded with many light burbs, to create bright atmosphere.

6. When you put your digital camera on a tripod, there is no need to choose high ISO number. Actually, using tripod is more suitable to record stabilize objects.

You need to be aware that high ISO images may look quite good from LCD screens. However, once you print high ISO camera images out, you will know differences compare with low ISOs. Moreover, you need to make noise reduction if you do not like too much grain on your photography, WidsMob Denoise is always your first choice.

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ISO Setting

Part 4: How to adjust ISO cameras with different parameters

ISO system is the rule to measure sensitivity of digital imaging systems, which is similar with film speed. Nowadays, you can set ISO number from ISO 50 to ISO 204,800. So you can balance exposure more in wider aspects. As you know, low ISOs are proper in bright areas or whenever you use a tripod to stable. For instance, ISO 200 with 1/250shutter speed is similar with ISO 400 at 1/500 shutter speed. Thus, higher ISOs need less light. As for people who shoot moving stuff in high speed, you had better improve into ISO 1600 or later, which can freeze motion more effectively.

Methods to Adjust ISO Cameras

As you have reading so much ISO knowledge, it is time to apply new skill. Though many digital SLR have different ISO icons. The steps to adjust on ISO cameras are similar. You can conclude ISO adjusting into two main steps, by pressing ISO icon ad choose ISO numbers. I will show you methods to get ISO value on Canon digital cameras.

1. Click the “ISO” icon around “Set” you will see all ISO numbers on your digital SLR. Use the ISO arrow to choose.

2. Adjust your DSLR into “P (Program) mode”, and go outside to shoot. It is the way to test your ISO camera quality. After that, you will have a clear realization of ISO settings. Upload ISO images to your computer to view.

3. Apply your DSLR into “Shutter Priority mode”, then take more pictures. Do not change other settings, I mean you need to take the same photos with the same lights. Import to your computer to compare.

4. However, it does not mean that once you need to freeze motion, you can just higher ISOs. Only by daily practice and shooting experience can you handle the exact ISO speed difference.

Because high ISOs can work faster, thus, camera shake does not influence very much, compares with lower ISOs. Though your images may be noisy with high ISOs, your ISO photos will be sharper than normal ones.

Adjust Camera ISO

Part 5: Tips to link ISO, Aperture and Shutter Speed for a good exposure

Actually, ISO is just 1/3 of photography’s exposure. To get correct exposure, you need to combine aperture and shutter speed together. Aperture controls depth of field, and shutter speed represent exposure duration. ISO sensitivity links with noise, which has been mentioned. Thus, it is time to make aperture and shutter speed clear.


In brief, aperture is the hole, which controls the pass of lights. But do not just regard aperture in such simple way totally. Aperture does not have affairs with lens, it is the place lights can travel through DSLR directly. To be more specific, aperture has divided into several f-stop values, you can call it focal ratio as well. Stopping down or opening up your lens means increase or decrease f-stop value. The common f-number is f/1.0, f/1.4, f/2.0, f/2.8, f/4.0, f/5.6 and f/8.0. The higher aperture is, the smaller depth of filed will be.

Shutter Speed

You can get certain information just from its name, shutter speed is the time of a DSLR sensor being exposed to light. The slower shutter speed has been, the more lights camera sensor will collect. People often apply slow shutter speed in dark places, such as nigh sky photos. Shutter speed has some connection with ISO speed, both of these two exposure points can freeze motion in a degree. The frequently use shutter speed is 1/15, 1/30, 1/60 and 1/125. In addition, high shutter speed can protect digital cameras from shake, which can maintain sharpness.

How to Combine ISO, Aperture and Shutter Speed to Get Good Exposure

Though Auto mode can help you solve normal daily photos, you still need to use manual mode if you want to get images with specific specials. As soon as you change into M mode, you will see the exposure list. After that, turn aperture and shutter speed to make exposure to 0. Now it is time to check ISO, Aperture and Shutter Speed.

  • Change aperture dial according to your need. If you prefer photos to be sharp, you need to get higher aperture, such as f/16.
  • Operate the same steps for shutter speed, as well as ISO sensitivity. Adjust into the combination you like.

The relationship among aperture setting and shutter speed is that, the higher aperture has shown, the slower shutter speed will be. Increasing ISOs can also cause high shutter speed. In addition, if you cannot decide how to balance exposure, you can turn back to Auto mode to seek for answers.

Aperture ISO Shutter


As for many people who just use iPhone to take photos, choosing ISO sensitivity does not influence too much. Though you may often use photo editors to modify or shooting with, things are totally different when you use the true digital SLRs. ISO is just the 1/3 of exposure, and exposure is also a small part of photography. But do not be worrying that it is too difficult to shoot when you are beginners or amateurs. The true shooting experience is the most important part for you to improve DSLR skills. You can also regard digital cameras as something to record your life in more delicate way. As you practice frequently, you will handle ISO skills naturally.

Though ISO volume have many divisions, the high ISO and low ISO are not fixed. If the lights are bright, using ISO 100 is enough in most cases, of course, not including something moving in high speed. Film grain and image resolution are two factors, which cannot avoid, if you really want to remove them out, there are many available denoise software waiting for your choice.

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