What size the photo should be for printing. Pixels, resolution and printing of digital images. How to calculate dimensions for high resolution

Taking photographs is a creative process. No wonder it has been raised to the rank of art. Famous photographers organize exhibitions on a par with artists. Good images are valued and generate income.

Photo has long been included in our daily life. Instead of memorizing a schedule or phone number, it's easier to take a picture using the camera's built-in phone. The way photos are stored has also changed: many do not print photos, but store them in electronic format. At any time, pictures can be viewed or sent to friends. But technology is improving, and the possibilities for using images are almost limitless. This applies to both the commercial sector and private photo sessions. All new photo formats appear and you can now print a picture in any size, having previously cropped it.

Photo formats for printing

Despite the development of digital photography, printed photographs have not lost their popularity. For example, photographs for documents, as before, are required on paper. There are paper banners and posters hanging outside. You can print photos on literally any surface - on a T-shirt, mug, or your smartphone case. Taking a photo is not a problem. It is important to select the correct photo sizes for printing on site. Even if you succeed in capturing the perfect photo, it may not be suitable for printing.

Let's take a look at the main photo formats for printing.

ISO standard formats

Formats that you probably heard about back in school. These are the same letters A with numbers. The table below shows the formats and their exact dimensions.

ISO standard	Size (cm)
A1	59,4x84,1
A2	42x59.4
A3	29,7x42
A4	21x29.7
A5	14,8x21
A6	10.5x14.8

It is worth paying attention to these parameters, since office equipment is produced taking into account these values. For example, the once-beloved 10x15 cm photographs are in fact standard A6 with minor adjustments.

Print formats are not limited to international photography standards. There are also other photo sizes. Each photo workshop has a table that lists the photo formats and their purpose. If you plan to print at home, you can find a similar table on the Internet and refer to it when editing images before printing.

Photo formats for documents

We should also talk about photographs for documents. Image sizes for documents are also standard. Image sizes correspond to a specific document. The largest photos are needed for personal affairs (9x12), the smallest - for military ID cards and driver's license (2.5x3.5).

Square photos

There is a small group of specialized formats such as squares. Nowadays, photos in this format can be found mainly on social networks like Instagram. The most interesting example is photographs taken with the Polaroid.

The most popular sizes for square photos are as follows:

Large format photos

With the development of technology, wide-format photographs are becoming more common, that is, photographs in which the length is several times greater than the height. They are notable for their similarity to the panoramic image. For a long time, advertisers had the opportunity to use a large-format plotter with a size of 10000x5000 for printing banners, thus there was no need for composite compositions.

Why consider image resolution?

Playing with the scale in the photo editor, you can get small pictures, or vice versa, you can enlarge the image in size. But there is a problem with the quality of the photo. It is not enough to choose a format for printing, you must take into account the resolution of the picture. A digital image is made up of pixels. The number of dots per inch indicates the clarity of the picture and is called the resolution. The more dots, the clearer the photo will be when printed. For example, to obtain a picture that will be easy to process, a resolution of 300 dpi is sufficient. When printed on a 8x10 cm sheet, in the editor you will get a size of 2400x3000 pixels.

Subtleties of photo editing

If the image format is non-standard, then before printing it is better to use a photo editor and change the resolution of the picture.

Also, if you want to print a small photo on a large format, the image will turn out to be fuzzy and blurry. Therefore, think in advance where the picture will be used.

Even an old photo can be printed on paper - you just need to set the correct format. And to set the correct scale and aspect ratio, use the simple and intuitive photo editor from Movavi.

There are two ways to resize the resulting image in Movavi Photo Editor:

1. Resize photo

1. Click the tab The size on the main toolbar
2. Use ready-made profiles or set your own photo size:

• Enter values \u200b\u200bin the block Fit to size... Click on the icon Maintain proportionsto scale the aspect ratios independently.
• Select a ready-made profile.
• Click on Other sizeto see all available profiles.

Click the button Applyto save your changes.

Crop the photo

1. Go to the tab Pruning.
2. Set the required size:

• Please indicate width and the height in the appropriate fields.
• Select the appropriate profile from the list.
• Set the parameters yourself. Position the frame so that you are comfortable with the resulting picture. To resize the frame, just drag its edges.

Click on Applyto save the image.

- jet or less often laser. We all know that there are certain popular photo sizes. But what are the standard photo sizes for printing? Let's summarize them in a table in which we give all the sizes of photos for printing.

Quite often, deciding to print our pictures, we are faced with a problem and ask ourselves - how big should they be? Of course, most modern digital cameras automatically select the required photo resolution values, but it also happens that you need to print photos downloaded from the Internet or captured on your phone, what should you do in this case?

First, let's answer the question - why should you know (and therefore adhere to) the standard photo sizes for printing? The fact is that having come up with standard photo sizes, photo paper began to be made of the same size. Therefore, the correct ratio of the height and width of the photograph is very important. Otherwise, the photos will turn out to be stretched both in height and width. The resolution of the picture is also important - it affects the quality (clarity) of the image when printing.

Photo sizes for printing are shown in the table

Where the standard or format is, this is the aspect ratio that it is desirable to adhere to so that you do not have to crop or stretch the photo. The second column contains the dimensions of the photos in centimeters, the third in pixels, I think that's understandable.

Standard sizesphotos have parameters 10.2 x 15.2 cm (highlighted in the table) - these are the usual photos for an album that we are used to seeing.

What if the image has different dimensions?

Suppose you compared the sizes of photographs for printing, the table of which was presented above, and found out that your picture has different dimensions, what should you do in this case? If the aspect ratio is different, then a simple increase or decrease in centimeters is not enough. You will have to crop the image to fit the desired format.

How to quickly crop a photo to the correct size?

There are two main ways.

The first way is to use the simplest image editing program. Almost all versions of the Windows operating system have paint program in the "Standard Programs" tab. Having opened a photo file in this program, you need to drag the border of the picture to the right or bottom and thus crop the photo to the desired size in pixels. The image size in pixels is shown at the bottom of the program window.

The second way is to use specialized image editing programs. Most often used photoshop program - she is the most popular and most professional. Note that we just need to adjust the photo to the desired format (depending on the version of the program, the location of this button may change - just squeak it on the toolbar).

For a novice user, the Photoshop program will seem like a magical tool that with mysterious ease can change any photo beyond recognition. But how!? Tell me! How he does it? What mechanism works? What is happening inside the photo that it changes as you like, as if it were a chameleon? Nothing complicated, you just need to know what digital photography consists of and what rules apply to it, then everything will fall into place.

Namely, Photoshop works with this kind of graphics, it consists of tiny elements - pixels, like any object of the smallest particles - atoms.

Pixels Are tiny square-shaped elements that contain information about color, brightness and transparency. The term comes from crossing two English words - picture (image) and element (element).

A digital image file consists of vertical and horizontal rows of pixels that fill its height and width, respectively. The more pixels an image contains, the more detail it can display. They are imperceptible to the human eye because they are negligible. To see them, you have to greatly enlarge the image:

Pay attention to . The visible part of the image is marked with a red frame. I zoomed in to 1200% on the area where the panda's nose and mouth are. As you can see, the image consists of a set of colored squares. When enlarged, it looks like a patchwork quilt made of square pieces.

Taking a closer look, you can understand the basic principles of image construction:

1. Pixels are square in shape and are arranged in the image in the form of a grid (remember a notebook sheet in a box).

2. The squares are always strictly of one definite color, they cannot even be a gradient. Even if it seems to you that some square is shimmering with color, then this is nothing more than an optical illusion. Increase this area even more and you will be convinced of this.

3. A smooth transition between colors occurs due to the gradually changing tones of adjacent pixels. Even the line of contact of contrasting colors can contain more than a dozen tones.

Image Resolution

Image resolution is inextricably linked to pixels.

Digital photography resolution is recorded as follows: 1920 × 1280. Such a record means that the image is 1920 pixels wide and 1280 pixels high, that is, these numbers are nothing more than the number of those smallest squares in one row and column.

By the way, if you multiply these two numbers - 1920 × 1280 (in my example, you get 2,457,600 pixels), then we get the total number "Scraps"that make up a particular image. This number can be reduced and written as 2.5 Megapixels (MP)... You came across such abbreviations when you got acquainted with the characteristics of a digital camera or, for example, a camera in a smartphone. Technology manufacturers indicate the limit that their product is capable of. This means that the higher the number of MPs, the higher the resolution of future images can be.

So, the higher the resolution, the smaller the pixels, which means that the quality and detail of the image increases. But a photo with a higher resolution will weigh more - such is the price of quality. Since each pixel stores certain information, with an increase in their number, more computer memory is required, which means that their weight grows. For example, the photo with bears at the top of the article with a resolution of 655 × 510 weighs 58 KB, and a photo with a resolution of 5184 × 3456 will take 6 MB.

Pixel sizes and printing

It is important to distinguish between situations when we are talking about pixel sizes and their effect on photo quality.

Looking at the images on the monitor screen, we see that the pixel dimensions are always the same. The computer resolution size is considered 72 dpi.

Note

Please note, when you create a new document in Photoshop, the program by default offers you exactly this value:

When viewing large photographs on a computer, for example, 5184 × 3456, one feels how detailed it is, there is no graininess and no defects, it is bright and clear. But believe me, such a photo is again 72 dpi. Let's open the properties of the image for the sake of interest:

A large photo will look great on a computer thanks to the scale. What is your screen resolution? Obviously not 5184 × 3456, but less. So the computer must reduce such a photo so that it fits entirely on the computer screen. The pixels are compressed and reduced in size, which means that here it is a cool image quality. If you were viewing such a photo at its original size, you could easily see the blurring and tarnishing of the image, as well as the sharp edges of contrasting details.

Pixel sizes are most often remembered when it comes to printing a photo. Here 72 points may not be enough.

For example, I created a document with dimensions 655x400 pixels with a resolution of 72 pixels. Look in the graph print size:

Photoshop has calculated that a 655x400 72-dot image can be printed on 9.097x5.556 '' paper (23.11x14.11 in centimeters)

655 pixels wide divided by 72 pixels per inch \u003d 9.097 inches wide
400 pixels divided by 72 pixels per inch \u003d 5.556 inches high

It would seem, “Wow! What a big sheet you can print on! " But in fact, the photo will be something like this:

Blurry photo, no sharpness and definition.

Printers are considered high-resolution devices, so in order for photos to be printed beautifully, you either need to print photos at an initially large size, like mine is 5184 × 3456, or change the number of dots per inch in the range from 200 to 300.

Again I will take the same image 655 × 400, but change the number of points to 200, this is what Photoshop writes:

The size of the print has decreased by almost three times. Now our image is printed at 200 pixels per inch of paper.

What happens is that the image will be small, it will hardly fit into a standard 10 by 15 photograph, but it will be of high quality, clear and detailed.

It turns out that there is a certain minimum resolution size for printing photographs. If the picture is initially small in size, as I had, then there is even nothing to think about good print quality.

What size should the image be in order to print it beautifully?

Let's say you came from Crimea from vacation, or took 100,500 photos of a child and, of course, want to print something into a photo album (example 1), and one of the most remarkable to make in the form of a picture on the wall (example 2)... Let's figure out what size such photos should be and whether modern cameras can achieve this.

Example 1

So, as a rule, there are photos of the size 10 × 15 cm (in inches this is 3.937 × 5.906). Now we will find out what should be the minimum photo size for everything to be beautifully printed. For calculations, we take a resolution of 200 dpi.

200 pixels per inch x 3.937 inches wide \u003d 787 pixels
200 pixels per inch x 5.906 inches high \u003d 1181 pixels.

That is a photograph 10 × 15 cm \u003d 787 × 1181 pixels, minimum (!)

And having found out the total number of pixels in this resolution (787 × 1181 = 929447 pixels), rounded to the nearest million, we get 1MP (megapixel). I have already written that the number of megapixels is the most important characteristic of modern cameras. The average number of MP in cameras and smartphones is about 8 MP.

This means that the current technology will easily make it possible to take photographs suitable immediately for printing pictures in 10 × 15 cm.

Example 2

Now let's analyze the case when you chose a photo and want to hang it on the wall in a frame measuring, say, 30 × 40 cm (I took the frame size from the IKEA store catalog), I will immediately translate it into inches: 11.811 × 15.748. For this photo size, I would take the maximum resolution size: 300 dpi, this is already considered professional and the highest quality print (just what you need for a large picture in a frame). And now the calculations:

300 pixels per inch x 11.811 inches wide \u003d 3543 pixels
300 pixels per inch x 15.748 inches high \u003d 4724 pixels.

Thus, your photo must be at least 3543 × 4724 pixels. Multiply the values \u200b\u200band get 16.737.132 pixels or 17 MP!

Thus, to print a framed photo, you need a powerful camera. This range is already being considered. And this is an expensive and serious type of equipment.

In general, and on the whole, you should now at least a little understand how the Photoshop program works and how all these photo editing frauds turn out. Having learned about pixels, their properties and capabilities, this process should no longer seem like magic.

If you spot an error in the text, select it and press Ctrl + Enter. Thanks!

»Table of standard photo print sizes

To prepare files for printing in one of the standard formats (from 10x15 to 30x90 cm), you can use this table.

format name		linear dimensions, cm	file sizes in pixels
			300 dpi	320 dpi
10 x 15		15.2 x 10.2	1795 x 1205	1915 x 1285
11 x 15	*	15.2 x 11.0	1795 x 1299	1915 x 1386
15 x 15		15.2 x 15.2	1795 x 1795	1915 x 1915
15 x 20	*	20.3 x 15.2	2398 x 1795	2557 x 1915
15 x 22		22.4 x 15.2	2646 x 1795	2822 x 1915
20 x 30		30.5 x 20.3	3602 x 2398	3843 x 2557
21 x 30		30.5 x 21.0	3602 x 2480	3843 x 2646
30 x 30		30.5 x 30.5	3602 x 3602	3843 x 3843
30 x 40	*	40.3 x 30.5	4760 x 3602	5077 x 3843
30 x 45		45.7 x 30.5	5398 x 3602	5757 x 3843
30 x 90		90.0 x 30.5	10630 x 3602	11339 x 3843

* Asterisk marks formats with an aspect ratio of 4: 3. Pictures from digital cameras can have an aspect ratio of either 4: 3 or 3: 2 - depending on the manufacturer and the characteristics of individual models.

File sizes in pixels are calculated based on the print resolution of the equipment on which standard formats are printed - 320 dpi.

Urgent photo printing and photobook printing are performed with a resolution of 300 dpi.

Note:

A small part of the image will always bleed out regardless of the values \u200b\u200bof the "crop" parameter. This is due to the technical tolerances of printing machines for paper play. We do not recommend placing significant parts of the image (for example, signatures) closer than 2 mm from its edge.

In cases where the aspect ratio of the image and the selected print size are the same, we recommend selecting the crop mode “Bleed (borderless)”. This avoids the appearance of narrow white streaks around the edges of the print, which can be caused by natural backlash in the paper feed.

In order to print an image "pixel to pixel" without scaling, it is necessary to select the "real size" crop mode. In this case, to compensate for paper backlash, we recommend preparing files with a margin of width and height, but no more than plus 60 pixels on each side.

The moment you take a photo, the camera receives data that creates a digital image. There are many different file formats that can be extracted and processed using editing programs. The most commonly used are the following:

Choosing the right format is very important and can be critical depending on the quality and level of processing you intend to do. Here are the pros and cons of using each of the file formats.

JPEG (Joint Photographic Experts Group)

TIFF (Tagged Image File Format)

DNG (Digital Negative Format)

PNG (Portable Network Graphics)

GIF (Graphics Interchange Format)

BMP (Bitmap)

PSD (Photoshop Document)

Jpeg

This is probably the most well-known image format, and one that most digital cameras provide as an off-the-shelf product. You should be aware that JPEG files are compressed quickly in the camera and thus result in a loss of detail and quality. They are essentially designed to store as many images on a memory card as possible. Some cameras provide options for the quality of the JPEG file (for example, low, medium, and high). This basically means that the better the quality you want, the less the camera will compress the original photo.

In general, JPEG is used for the following purposes:

When photographs are intended for personal use, social media, albums and print in small format, but not large.

When you do not intend to subject the image to intensive processing (for example, using Photoshop);

To send images by e-mail (for no purpose later to print them in large format).

Benefits

• Small size means more photos will fit on the memory card
• Faster file transfer due to small size

disadvantages

• Loss of quality due to image compression
• Less room for image manipulation in photo editing programs.

Tiff

This is the most commonly used standard file format used for printing or required by publishers. Even if the file is ultimately needed in JPEG, the originally created file will be in TIFF. It is usually not compressed and as a result allows for extensive post-processing. For the same reason, the file size is much larger, so it will take up more space on the memory card and disk of your computer. Some cameras offer TIFF as the highest quality format.

Benefits

• Extensive manipulation of image processing
• High quality and large format printing

disadvantages

• Larger file size (needs more storage space)
• Longer transfer and download times due to file size

RAW

The RAW format is commonly available on advanced compact cameras and DSLRs and is easy to install; it is the best choice if you want to get the most out of your camera and is preferred by professional photographers. The problem is, by not using the raw file format, your camera will make adjustments that will affect your photos.

Raw files are compressed in such a way that all the information originally received is preserved. This means that settings such as white balance, exposure, contrast, saturation, sharpness can still be changed using the editing software after the photo has been taken. Taking pictures in this format will require a lot of space on the memory card, not to mention the time for post-processing. It will also require some basic knowledge of editors such as Adobe Lightroom or Photoshop, as the files must be edited and converted before they can be used (share online, print, send to friends, etc.)

Benefits

• This is the highest image quality file
• Wide possibilities in post-processing and image manipulation

disadvantages

• It takes time to convert and edit photos (you are editing raw files)
• Large file sizes will require more storage space and more post-processing time

DNG (Digital Negative)

Almost every camera these days uses its own format to receive raw files. Even cameras from the same manufacturer often use different formats, which means that the software must be able to read files from different cameras and formats. As a result, the problem that software developers face is how to manage and continually provide updates to their software products so that they can read all camera formats.

So DNG. Created by Adobe, this file format is an effort to create a standard file format for all manufacturers and cameras. It has been proposed as the main raw file format or as an alternative to the manufacturer's native format. One of the problems with keeping files in their original format is that you may not have access to them for years to come, as they are specific to a particular camera and manufacturer. But using Adobe DNG Convertor means you can save your files in DNG format for maximum security. This actually adds another step to the post-processing process, which will take additional time. However, if you use a program like Lightroom, it will help you convert large batches of files so you don't have to do it manually.

Benefits

• Ability to use editors such as Lightroom and Photoshop
• Probably safer option in the long term to protect against being unable to open or access files

disadvantages

• Additional time is needed to convert the original camera files to DNG (if your camera does not have the ability to create files immediately in this format)

PNG

Developed in the 90s as an improved version of the GIF format, PNG files are ideal for use on the web. The advantage of PNGs is that they are losslessly compressed while retaining all the digital details. But unlike other formats, this quality does not imply a large file size, which is not entirely convenient when you want to quickly upload an image on the Internet. Another advantage of PNG files is that they allow for partial (drop shadow effect) or full transparency, which is ideal for overlays and logos.

Benefits

• Lossless compression means good quality that won't be compromised when editing
• Ability to maintain transparency, ideal for things like overlays and logos

disadvantages

• Quality will not be sufficient for printing at any size

GIF

Like PNGs, GIF files are ideal for use on the web. Lossless compression means that the image quality will not be affected, and like PNGs, they also have the ability to support transparency (but do not support partial transparency) and can be used for animation. However, the limitations of GIF files are that they can contain a maximum of 256 colors, and therefore are not the best choice for photographs, but rather for images with a limited color palette.

Benefits

• Small file size makes them ideal for Internet use
• Files can contain animation

disadvantages

• Limiting colors means it's not the best choice for photos
• Doesn't support partial transparency like drop shadows

BMP

Another lossless format, BMP, was originally developed by Microsoft for use on the Windows platform, but is now recognized by Mac programs as well. BMP files are large files because color information is stored in every single pixel in an image without compression. As a result, this produces a high quality digital file that can be used for printing, but not quite suitable for the Internet.

Benefits

• Can be used for printing as the images are saved in high quality format

disadvantages

• Large file sizes will require a lot of storage space

PSD

This file type is used by Adobe Photoshop by default for saving data. The big advantage of PSD files is that they allow manipulation on specific individual layers rather than on the image itself. This is essential for extensive image manipulation such as retouching. This gives much more flexibility and the ability to fine-tune the image, since layers can be added, removed, edited at any time, without affecting the original image (as long as they are done on the layers) or other layers. But remember that once the layers in the PSD file have been merged (this process essentially merges all the layers), it cannot be undone, so be sure to save your file as a PSD before merging the layers.

Benefits

• Possibility of wide control in the image on separate layers
• When the image is ready, you can resave it in any other format

disadvantages

• A multi-layered file can be very large due to the additional information stored.

There are a number of the most used and common file types. Professional photographers usually shoot in raw format (even if the final file is needed in JPEG), convert to DNG, then edit the photo in programs such as Photoshop or Lightroom. But, as you can see, it is very important to choose the right format for creating the original photo and then saving it.