The use of some terms in digital imaging has become a matter of great confusion for many people. If you have ever wondered what is DPI of an image, it is a cumbersome task for a layman to differentiate between Dots per Inch (DPI) and Pixels per Image (PPI).
Well, both DPI and PPI are the measure of resolution for both on-screen and print images. It is pertinent to note that DPI is relatively an old term. People have been using this very term to relate everything about the digital images and their size and resolution before the appearance of PPI in recent years. Currently, PPI is most commonly used to manage the resolution and scale of digital photos, yet DPI is still used for some software and documents.
The following lines explain what Dots per Inch (DPI) means and how it affects the resolution of your image.
If you don’t know what is DPI in the image, you should know that the DPI refers explicitly to the printers. In some words, it is only used in printers nowadays. Everyone should be aware that all the printers consist of different colored inks that combine to create every single pixel output. There are usually 4-6 differently colored inks in a printer. The printer works on the principle of mixing all these colors to create an image.
The printer has to mix the inks because of a small number of colors available to it. It has to create an image using only these 4-6 colors. A series of tiny dots create each pixel of an image. You can consider these tiny dots as sub-pixels. It is important to note that the tonality of the printer will be higher if there are more dots per inch in an image, and this is what is DPI of image.
All the images follow the same old rule more DPI better quality, that is higher the DPI, the better will be the quality of the image. Moreover, the resolution of a digital image is incomplete if you do not request the size of the print along with it.
Colors in the image will also look better if the DPI is higher. Most importantly, the colors will blend naturally and smoothly. There is also a reverse side of using high DPI in image processing. That is the printing job will be slower, and the printer will use more ink. To overcome this problem, you must try to lower the DPI setting without distorting the DPI image. The lowest DPI setting, which does not reduce the DPI image quality is the one you should be using.
Against common perception, DPI meaning has nothing to do with the video quality. Almost all the modern video formats, as well as rasterized images, store their data solely as pixels. They do not depend upon DPI or real-world measurements such as inches for their quality. On the other hand, monitors also display video only in units of pixels. If you are displaying a video or rasterized image, the monitor maps them pixels by pixels instead of dots per inch.
You may have to use DPI in videos and rasterized images when you want to map real pixels into real-world measurements. For example, 20 points are roughly 0.28 inches. Therefore, a 20 point Font will use dots per image settings to determine how many pixels it should use.
Now, we will answer what is DPI resolution best for your image. You might be surprised to learn that most pros recommend using 300-400 DPI resolution for digital photos. This raises a fundamental question: what does higher DPI do. Why not use higher 1000 or 2000 DPI for an image or for that matter, lower 120 DPI? Is there a threshold for lower and higher image resolution beyond which you should not venture. Professionals consider 300 PPI photos as a high resolution, but when printed, that’s why professionals recommend it and suitable for most of the users.
It is also pertinent to note that an image with 72 DPI might look amazing on your computer screen. However, you may be shocked to test the image on your 20 HDTV7. The low dpi vs. high dpi picture is a long time doubt to many people. Although 400 DPI is always better than 120 DPI, the actual DPI resolution you want to use depends upon the type of image and your requirements.
For instance, most old photo labs would develop your photos using only 300 DPI physically. 300-400 DPI is still good enough for most of the photos. For example, if you scan an old photo at 300 DPI, you are very likely to get an exact copy of your photo. On the contrary, if you scan it using 600, 900 or higher DPI, it will distort your photo instead to provide you with more details. 300 DPI is the limit for such photos, and you should not go higher or lower.
Again, the quality of the image depends upon the device on which you are viewing your image. You might distort your image if you want to get the bigger print of your 300 DPI photo. This is where you must scan your image at a higher DPI. It will help you retain the image quality without stretching the picture.
Yeah, we just told you that the higher the resolution better the quality of an image. But pictures with the same PPI can also have different variety of an image. You can follow some of the tips listed below to improve the quality of the image:
You must be thinking does DPI affect file size? Long answer short, the DPI can also change the physical size of the image. You might have to increase or decrease the DPI to set the image to the default size of the printer you are using to print the image. For example, the DPI of the photo should be 400 if the default print dimension is 5 inch and you want to set the image width to 2000 pixels. The formula is simple. You will divide 2000 with 5 to get 400 DPI.
You should try not to resample or resize your image while changing its DPI. It is advisable to retain the original pixel dimensions while changing your DPI. These pixels usually determine the real digital resolution of an image. Image quality DPI means you will be able to retain the size and resolution of the original image without distorting its quality. The only thing you will be changing is its inner dots per inch (DPI) dimensions.
There are many programs such as Photoshop and Illustrator, which help you change the DPI without disturbing the physical size of the image. The only thing you need to keep in mind is that you should never resample or resize your image while changing the DPI. Your new photo will be a carbon copy of the original as long as its pixels remain unchanged.
It is essential to set the correct DPI of an image; otherwise, you might end up having some glossy, blurry, or low-quality photos. So, you must know how to change the DPI of an image. You can easily change the DPI of an image using photoshop. Open your photo in photoshop and go to image, and then Image size. Make sure to uncheck the resample image button as it will further deplete the quality of your image.
To increase dpi of image type your required resolution and set it as Pixels per inch. The width and height of the image will change automatically based on your preferred choice. You can also adjust the height or width of the image, and DPI will adapt accordingly.
To conclude, we would recommend your images to have a resolution of 300 dpi or higher if you want a high-quality printed copy. We often see that a web image printed becomes blurry, and due to lest PPI, the images get distorted a lot. Images for newspapers can usually be around 200 dpi due to the low quality of the paper. And if you want a web image you can use 72 dpi image size as images with higher DPI will be reduced to display at 96 dpi or less.
While creating an image, resolution, and quality are often neglected, but it is essential for any photo when you are putting so much effort and time. So, we hope you are clear with the DPI meaning and make sure to choose the right resolution for your image next time you want to click a perfect candid.
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