Generally speaking, the more megapixels an image has, the higher its resolution and level of detail. This is because a higher number of pixels means that the camera is capable of capturing more information.

Similarly, if you are an advertising or fashion photographer then ultra high resolution sensors can mean a lot more flexibility in production. Just imagine an editorial photographer taking a single full length portrait, and then being able to create printable crops focusing on the subjects facial expression, dress, wrist, neck jewelry and shoes, all from one shot!

In just 90 seconds, we unravel the mystery behind megapixels to help you determine whether or not you need more of them.

Depth of field (DOF) is a crucial concept in photography on a technique and artistic scale. Since photography is a two-dimensional art form, depth of field gives us the ability to feel as though we are stepping into an image. Your depth of field is also known as your focus range. The “field” is the subject you are photographing, and the depth is the distance between the nearest and furthest objects that are sharp and in focus.

Depth of field

In other words, highly proficient photographers that are seeking cameras that can print directly to large format with incredible detail reproduction or provide extreme cropping capabilities can utilize cameras with 30, 50, or even 100 MP.

The image above is shot with the 36 megapixel Nikon D800. With this much resolution, there is plenty of room to crop the image and still produce high-quality photos. The example below is a 100% crop sample from the previous image, and as you can see we still have enough detail left to use for either posting on the web or even printing.

Depth of focus

However, it’s important to note that simply having more megapixels doesn’t necessarily mean that the image will be higher quality. Other factors like lens quality, sensor size, color resolution, dynamic range, and more play a role in determining image quality.

dof自由度

Megapixels (MP), which translates to “one million pixels,” dictate how much detail your camera’s sensor can capture.  In digital photography, the number of megapixels in an image refers to the total number of pixels that make up the image. To determine this number, multiply the number of pixels in the width of the image by the number of pixels in the height of the image.

Do we all need $50k cameras that produce 100 MP images? Not exactly. Most cameras feature 20-40 MP these days, and yet most photographers don’t use their camera to its potential. A camera with a 20 MP sensor will only yield 20 MP worth of detail when it is used by a proficient photographer. The means the photographer must understand how to maximize detail and resolution using lighting and other means.

You can also change your depth of field based on your camera lens; this can get a little more tricky. The more you zoom, the more depth you will receive because it is also compressing your image and you will have more of a focus on your field rather than use a wide-angle lens. Using a wide-angle lens is great if you want a deeper depth of field and more in focus. The higher the focal length, the shallower your depth of field will be because it is compressing your image.

Depth of field calculator

This also applies if you display an image photographed in landscape orientation in a vertical (or portrait orientation) format.  For example, to place a landscape orientated photo in a vertical slideshow format, such as an Instagram reel, a higher megapixel count will work better.

While it’s true that other factors beyond megapixels can compensate for lower megapixel counts, there are situations in which high megapixel counts are necessary.   For example, when sent to print, a 20 MP file can yield an 18″ wide print without any upscaling in Photoshop or other photo editing software. Yet, how often do you print 12″x18″ photographs? For most consumers, the answer is “not often.”

When an image is straightened or cropped in post production, resolution is lost.  So, if you crop your images heavily, a higher megapixel count will give you more flexibility.

Sheer resolution becomes a factor when enlarging and performing extreme crops. For example, because detail is more visible when blowing a photo up to a 20×30 inch canvas versus a 4×6 inch print, having a higher megapixel resolution is important in bringing out more crisp details in your enlargements. Also, if you happen to have a 40 megapixel image, and need to crop 80% of the image, you will still have plenty of detail left for that enlargement.

In the world of digital cameras and smartphones, marketers use the term “megapixels” frequently to describe the quality of the images produced by these devices. But what are megapixels exactly, and do they really matter? Megapixels refer to the number of individual pixels that make up an image. The more megapixels, the more detail and resolution the image can have. However, simply having more megapixels doesn’t necessarily mean better image quality. In this article, we’ll dive deeper into the world of megapixels and explore their role in determining the quality of digital images.

Depth of field can give you as much or as little texture that you are looking for in an image as well; this comes in handy while shooting macro photography. You can see in this example just how much the background texture changes from 2.5 to 5.0.

A deeper depth of field is common when photographing a landscape and architecture. When shooting a landscape, you will want to have your foreground, middle ground, and background crisp and in focus. The higher your aperture is, the slower your shutter speed will be to get a correct exposure so always be prepared with a tripod while shooting landscapes in lower light to avoid any camera shake.

DOFsimulator

You might often hear of a “shallow” or “deep” depth of field. A shallow DOF has less focus around your main subject, and a deep depth of field shows more focus around your main subject. The aperture easily controls the depth of field. Aperture is made up of f-numbers (f/5.0, f/16, f/22) and is also known as f-stops. The higher the f-stop number, the deeper your depth of field will be and the smaller the f-stop number is, the more shallow your depth of field will be. Aperture also has an effect on your exposure. The numbers represent the lens opening diameter size, and that will also determine how much light passes into the camera. The range starts at a larger diameter size and works down. The smaller the f-stop, the larger the diameter of the lens opening, this also adds more light. The larger the f-stop, the smaller the diameter and the less light will pass through.

In conclusion, while megapixels can act as a helpful indicator of image quality, they represent only one of many factors that determine the quality of a digital image. Other factors, such as lens quality and sensor size, also play a significant role in determining image quality. Whether or not megapixels matter ultimately depends on your intended use for your images. By considering your needs and how you plan to use your images, you can determine the appropriate level of megapixels for your photography.

For example, a studio that shoots 150 weddings per year may produce over a million RAW images per year. At 40-50+ megabytes per image, that comes out to 25-30 Terabytes of storage!  Of course, the average shooter may only have to buy one or two extra memory cards and hard drives. Storage needs will vary based on your personal workflow volume.

Another consideration is editing speed.  Let’s consider again the wedding photographer who generates roughly 3,000-5,000 images per wedding.  Even if the difference in editing time equates to a few seconds per image, the workload can increase significantly. If you double or triple the megapixel count, editing time can increase by quite a few hours per week.

Additionally, the level of detail that can be captured by a high-megapixel camera may not be noticeable unless the image is viewed at a large size. For example, the image below was shot with a 12 megapixel Nikon D700 and the image quality is stunning. One can really see the detail when viewing the image online, as a slideshow, or in 10-20″ prints. For these viewing conditions, the 12MP sensor provides more than enough resolution and allows for a small amount of cropping.

Shallow depth of field

Shallow depth of field is very common in portrait photography, wildlife photography, sports photography, and detail shots. Portraits are best with a shallow depth of field because it blocks out any distractions which can also apply to wildlife photography. Another good reason to use a low aperture is that it will add more light in. This will give you the ability to use a faster shutter speed to catch candid moments and a great tool to have for fast sports photography.

A third megapixel myth needs busting before we wrap up, and that has to do with down-sizing your high-res images.  Many people argue that down-sizing your high-res images is not as good as if you simply had a sensor with lower megapixels in the first place.  However if you compare image detail and dynamic range, this is not true.

depth of field中文

The bigger debate has to do with ISO performance and re-sizing high-res images. If you want the absolute best low-light performance, should you use a 16 MP sensor or a 36 MP sensor?  Without getting too geeky, suffice it to say that by re-sizing a high-res image, you do indeed gain a considerable amount of low-light performance. At least, you get better noise reduction performance.

Additionally, if you shoot a high-volume of images like for a wedding or action sports, then you may not want 4,000 images at 40 megapixels per photo shoot. When shooting at that rate, it won’t take long to run out of hard drive space.

Most images end up online, usually on social media. However, online and social media usage rarely exceeds 2MP. That means the other 18 MP you paid for never really get seen. Even a 4K display can only present 8 MP worth of your photograph.

Compared to the Nikon D800, the Phase One medium format camera has more than twice the megapixels, resulting in an incredible amount of detail saved even after extreme crops.

The image above is taken with a staggering 80 megapixel digital back sensor. Even at just 50% crop, we can still get beautiful details of the model’s face, clothes, and jewelry with enough resolution for a full-page spread publication!

Depth of field is only one piece of the exposure triangle but, as you can see, it offers a lot of tools to make your photography stand out.

What is DoFin photography

The easiest exercise to demonstrate aperture and how it affects your depth of field is to set your camera on a tripod and find a subject that shows a foreground, middle ground, and background. A tripod is not only important in this because you want to have a continuous shot but because your shutter speed is going to start slowing down to compensate for the light as your DOF goes up. Set your camera to AV which is aperture priority. This will let you change the aperture how you please and lets the camera choose the shutter speed and ISO for your best lighting.

For example, if we compare images from the 16 MP Nikon D4 and the 36 MP D800, with the D800 image re-sized down to 16 MP, we’ll see far more detail in the D800 16 megapixel image.