To remove a header and footer, simply uncheck the box in the Page Style window in the corresponding tab. On page header or On footer.
You can also in the corresponding window tab Header & Footer (Page Style…)(see Fig. 15.19) in the drop-down list Page header (footer) select parameter No.
Setting up sheet printing features
Printing Sheet Elements
Typically, OpenOffice.org Calc worksheet elements such as column and row headers and the grid are not printed on paper.
However, in some cases, such as when printing notes on separate page, for ease of use, you can print row and column headings.
Or, for example, you can not set the borders of the table cells, but instead print a grid. The grid will be printed only in active area sheet, that is, where there is any data or objects.
To print the named sheet elements, select the appropriate checkboxes in the tab Sheet dialog box Page style(Fig. 15.21).
Printing graphics
By default, all graphic objects located on the sheet are printed. In the tab Sheet dialog box Page style(see Fig. 15.21) there are three checkboxes that allow you to control the printing of objects.
To refuse printing of graphic objects (pictures) inserted from graphic files or the Gallery, uncheck the box Embedded and graphical objects.
To refuse to print diagrams, uncheck the corresponding box.
To not print pictures created using the toolbar Drawing functions, as well as the notes displayed on the sheet, you should uncheck Drawings.
Printing notes
By default, all notes displayed on a sheet are printed as they appear on the sheet.
You can print all the notes for all cells in text form on a separate page (or several pages, if there are a lot of notes). To do this, just go to the tab Sheet dialog box Page style(see Fig. 15.21) check the box Notes.
To prevent frames with displayed notes from being printed, you should uncheck the box in the same tab Drawings. In this case, of course, other drawn objects will not be printed.
Printing formulas
In rare cases, for example, when searching for errors in formulas used, you can print formulas in cells instead of calculation results. To do this, go to the tab Sheet dialog box Page style(see Fig. 15.21) check the box Formulas. In this case, the calculation results (values) will still be displayed in the cells on the sheet.
Printing null values
For the convenience of working with a printed table, you can refuse to print zero values in cells. Moreover, it does not matter whether these zero values were entered from the keyboard or were obtained as a result of calculations. To do this, go to the tab Sheet dialog box Page style(see Fig. 15.21) uncheck Null values. In this case, the worksheet will still display zero values in the cells.
Print Sequence
When the table is located on several pages, by checking the appropriate box, you can select the printing order: from top to bottom, then to the right or from left to right, then down (see Fig. 15.21). This choice determines the page numbering sequence, as well as the order in which pages are displayed in preview mode.
Setting the print scale
Setting a custom scale
By default, the print scale is set to 100% of the actual size of the table on the sheet.
By dragging the slider or using the "+" (plus) and "-" (minus) buttons located in the toolbar Preview(see Fig. 15.2), you can set any print scale.
It is difficult to set the exact scale using the slider, so you can use the tab Sheet dialog box Page style and in the counter Coefficient(cm.
1.2.2. Resolution selection
Any human community, a stable quorum, an established social organism has some relatively stable “agenda” - a set of discussed topics that attract the attention of all members of the informal team. This is the behavior of sports fans, collectors of any kind, members of political parties, fans of pop stars, etc.
Similar behavior is demonstrated by a virtual community of people united by the possession of a personal computer. To verify this, you do not need to conduct sociological measurements or conduct a public opinion poll. It is enough to familiarize yourself with the topics and content of popular Internet forums. In any teleconference dedicated to the operation of computer peripherals, the choice of scanning resolution is one of the most representative branches.
Scanning at low resolution settings may not produce an original High Quality. This thesis is obvious and does not require special evidence. Some users, without deep reflection about the correctness of their decision, process originals of any type with the maximum settings available for the scanner. According to them, there is never too much resolution; redundant data received by the scanner will simply be discarded by the final output device: a printer or monitor. A convincing justification for the fallacy of such ideas is given in the book by D. Margulis “Photoshop for Professionals”. We will not repeat his arguments; we will only mention the problem of memory.
Previously, calculations were given showing a high volume velocity graphic file with increasing resolution. If you digitize a full-color image onto a quarter sheet of paper with a resolution of 600 dpi, you will get a file of approximately 25 megabytes. As you increase the format and resolution, the size of the graphic data will quickly increase. Modern scanners allow you to process originals with a resolution of 1200 dpi and much more. In this case, the count is already many hundreds of megabytes. Processing files of this size is a task solvable only for personal computers of the highest class. Its implementation will require exclusive ownership of computer resources and will lead to a significant overload of all components of the computer system. Working in this mode often causes crashes technical support and car freezing. Why pay such a price, knowing that most of the data is ballast, “waste rock” that does not affect the quality of the result.
Choose better resolution scanning is not an easy task. There is no exact algorithm for solving it yet. The practice of scanning is large, but only a small fraction of it is fully documented, much less formalized. Most of the digitization experience exists in the form of advice, recommendations - in a word, in a form that in computer science is usually called heuristics.
It is more convenient to solve this problem from the end. To select the optimal scanning resolution, you need to provide clear answers to the following questions:
- What type of output device is the original being scanned for? Color monitor, inkjet printer, printing press, photo printer - devices with completely different principles actions and visualization technology. It is clear that for each of them the optimal resolution lies in its own range of values.
- What will be the true dimensions of the original? If, after digitization, the image is supposed to be enlarged, then the scanning resolution should increase relative to the norm set by the type of output device. Many other factors also influence: the type of paper and its coating, print quality, color model of the original, the presence of text fragments, etc.
Print scaling
In many cases, the dimensions of the original original and the printed version may not be the same. The need for scaling is explained by reasons of a wide variety of properties. These may be direct requirements of the customer or conditions; the latter are imposed on the image by the layout of the original layout.
Let there be an original measuring 4*x4 inches, which is digitized with a resolution of 100 dpi. A simple calculation shows that scanning will give digital image, consisting of 400*400 points. If you print it with a resolution of 100 dpi, you will get a printed copy whose dimensions coincide with the dimensions of the original object. From a methodological point of view, it should be expressed differently. Printing a screen version while maintaining its original dimensions requires selecting a printer resolution of 100dpi.
What happens if the number of pixels in a digital image is left unchanged, but the size of the printed image is increased? An 8*8 inch image will be printed with a resolution of 50 dpi; dimensions 16*16 will require an even lower resolution of 25 dpi.
In order to catch a trend, there is no need to multiply calculations and provide cumbersome numerical tables. Enlarging the printout of the screen version results in a loss of quality of the printed image. If with small scaling the degradation of image quality can be neglected, then with a significant increase in size this trend becomes irreversible.
You can prevent loss of quality when scaling a print by increasing the number of pixels in the digital image. This means that originals that are supposed to be enlarged during printing must be digitized with some margin to allow for future scaling.
Let's assume that we know the optimal print resolution required in a given situation. Determining this number is a complex task that requires taking into account many factors. We will assume that for our hypothetical case it has been successfully solved. In this case, the digitization density of the original can be found using the formula:
Scan Resolution = Print Resolution * Zoom Factor,
where the scaling factor is calculated using the following formula:
Scaling factor = Print Dimensions / Original Dimensions.
The scaling correction factor must be taken into account in any resolution calculations, regardless of the type of printing device and the type of original.
The problem of calculating the necessary correction for changes in dimensions can be assigned to the program that controls the operation of the scanning device. Any software tool This type is capable of taking into account future scaling of the printed output at the scanning stage. To do this, you simply need to enter the required zoom factor, leaving the scanning resolution unchanged. The program will perform all necessary recalculations independently.
The following table shows different options for obtaining enough numeric data to generate a hard copy given dimensions and quality.
|
Original dimensions |
Scan Resolution |
Scaling |
Actual Scan Resolution |
Original dimensions in pixels |
Default print resolution |
Print size |
| 1 4x4 inches |
100dpi |
100% |
100dpi |
400x400 |
100dpi |
4x4 inches |
| 2 4x4 inches |
200dpi |
100% |
200dpi |
800x800 |
200dpi |
4x4 inches |
| 3 4x4 inches |
100dpi |
200% |
200dpi |
800x800 |
100dpi |
8x8 inches |
In the first case, the resolution of scanning and printing is the same, which, in the absence of scaling, gives a print whose dimensions completely coincide with the original ones. The settings of the second option were obtained using a formula for calculating scanning resolution, taking into account the correction factor for scaling. The print resolution defaults to the scan resolution, which preserves the size of the original when printed. At first glance, there are no changes compared to the first option, but the increased number of dots allows you to print an image with a resolution of 100 dpi. This will allow you to get a hard copy of the required dimensions.
Finally, the third row of the table shows the calculation that the scan control program will perform at 200% zoom.
How does the scanner control program handle the scaling request? It increases the actual scanning resolution so that the resulting number of pixels is sufficient for high-quality printing of a scaled image. This conclusion is confirmed by a comparison of the first and third versions of the table. If the user specifies a scanning resolution of 100 dpi and an enlargement of 200%, the original will be processed at an actual resolution of 200 dpi. This will give the required 800*800 dots that are required for printing with magnification.
From a technical point of view, both methods of achieving scaling (explicitly increasing the resolution and setting the scaling factor) are completely equal and entail the same consequences. The following consideration gives a slight advantage in favor of the first method. When the user sets the zoom factor, they have no control over the actual scanning resolution, which may exceed the optical resolution threshold. If the scanning resolution is calculated explicitly, adjusted for scaling, then the result is easier to control.
Important! Print resolution and printer resolution are related but not equivalent concepts. The consonance and apparent semantic similarity of these terms are often the reason for their identification. It is very important to understand that these are related but not equivalent concepts. Print resolution is the coefficient for converting the number of pixels of a digital image into the actual dimensions of the printed print. This number is not related to the brand and type of printing device. This is the number that Photoshop displays on the left side of the status bar and in the Resolution section of the New and Image Size dialog boxes. To eliminate the slightest possibility of confusion, in some computer graphics publications it is called the output resolution, and the scanning resolution is called the input resolution. Printer resolution is a technical characteristic of a printing device. This is a stand-alone option, but for high print quality it should be selected based on the output image resolution.
Selecting resolution for offset printing
The modern printing industry has an army of the most different devices to obtain a printed copy. They differ in design, performance, print quality, and physical principles of operation. On one flank there are professional high-performance printing machines and phototypesetting machines, while the other is occupied by desktop office and home printers. Special devices for printing on non-paper materials have become widespread: films, fabrics, polymers, etc.
According to the basic principles of obtaining a print, all printing devices can be divided into two classes: devices with continuous tone transmission and devices that perform halftone screening. The principles of printing with continuous tone transfer have been studied for a long time, but for a long time this direction in printing has hardly developed. Only in our time have these devices begun to occupy a significant share of the printing equipment market. Most printing devices in circulation, from offset printing machines to simple inkjet printers, use the principles of halftone screening.
If printing based on the principle of continuous tone transfer can be compared to the work of a paint roller or a spray gun, then devices using halftone screening have in their arsenal only a zero brush and a modest palette of no more than four colors.
Halftone screening is a method of simulating shades with individual dots of ink or toner. In many respects, the human eye is an unsurpassed optical system, but its resolution is very limited. Therefore, many individual points of small size are perceived by the eye at some distance in the form of a uniform field. The brightness of the field depends on the degree to which it is filled with paint dots (Fig. 1.8). The fewer dots of dye applied to the paper, the lighter the tone or paint appears. This psychophysical property of human vision is used in halftone screening devices to convey gradations of brightness and color. Let's look at the principles of halftone screening using grayscale images as an example.
Rice. 1.8. Transmission of shades using a halftone cell. The more filled dots in a cell, the darker it appears to the observer.
The printing device applies dots of ink or toner onto paper and arranges them at the nodes of a regular rectangular grid, sometimes called a Physical Raster. We will call them printed dots. If you print the border in solid black and examine the image through a magnifying glass, the regular grid of printed dots will be clearly visible. The distance between printed dots depends on the resolution of the device and the size of the dots. The resolution (resolution) of a printing device - a printing press or printer - is usually measured in dots per inch (dpi). The higher the resolution, the closer the dots are to each other and, therefore, the finer details of the image are transferred when printed. Modern inkjet and laser printers have resolutions ranging from 300 to 4800 dpi. The resolution of professional printing equipment can be even higher.
Adjacent points on the printing device's physical grid are combined into rectangles called halftone cells. Another grid is formed from halftone cells, called a linear raster (Jine screen). A line raster is simply a way to logically organize a physical raster (Figure 1.9).
Rice. 1.9. Physical and linear rasters. The collection of adjacent physical raster dots forms a halftone cell, which is a logical unit in offset printing
When printed, image pixels are represented as halftone cells rather than dots on the physical raster of the printing device. By changing the filling of halftone cells with printed dots, you can simulate the brightness gradations of image pixels. Typically, cells are filled in a radial direction - from the center to the periphery. Printed dots can form various shapes, most often circles, ellipses or squares.
The frequency of a linear raster, or the number of halftone cells per unit length, is called lineature and is measured in lines per inch (Ipi). For example, a lineature of 100 lines per inch (100 Ipi) means that the printing device can produce 100 halftone cells per inch. Lineature is one of the most important parameters of the printing process, since the quality of printed graphics and text largely depends on it.
It is generally accepted that as the lineature increases, the quality of the images increases, and they become clearer and denser. This statement is true, as representatives of the exact sciences like to say, “all other things being equal.” Print quality will improve if the image gives reasons for this, that is, if it contains information that would be lost when printing with a low lineature. The catchability of a seine, of course, depends on the mesh size. But if only large fish are found in the reservoir, then straining it with a piece of mesh cloth with a small cell will not increase the catch.
Another one important characteristic prints are the dimensions of the halftone cell. The cell size determines the number of shades or gradations of gray that can be obtained when printing. Let, for example, a halftone cell have dimensions of 8 * 8 printed dots. Then you can use it to reproduce 64 shades gray, from light gray, when only one printed dot is entered into a cell, to black, for which all dots in the cell must be filled in for transmission. A cell with a side equal to 16 can convey 16 * 16 = 256 shades of gray. The human eye perceives about two hundred shades of gray. Printing a tonal-rich image using a small cell size can result in a poor tonal range of the printed output, resulting in distinct edges and spots that were not present in the original. Images with a depleted tonal range are called posterized. Sometimes posterization is used intentionally, as a special effect to achieve certain artistic goals.
It seems that the recipe for high-quality printing is simple. To ensure accuracy and correct transmission of tones, you should select sufficiently large values of the lineature and halftone cell sizes. However, everything is not so simple. Lineature and cell sizes conflict with each other “in the struggle for dominance” over the physical raster of the printing device (see Fig. 1.9). In fact, increasing the cell size leads to a decrease in the frequency of the linear raster. Conversely, increasing the number of screen lines leads to a reduction in the halftone cell.
The relationship between the lineature and the side length of a halftone cell is expressed by the following formula:
Cell size = (Physical resolution of the printing device/Lineature). From this expression it is easy to find the relationship between the number of shades of gray and the raster lineature:
Number of tones = (Physical resolution of the printing device/Lineature)2 + 1, or Cell size 2 + 1.
To print an image with all 256 halftones preserved, a halftone cell with a side length of 16 is required. If the digitized original has a resolution of 300 dpi, then to reproduce all the pixels bitmap The printed output will require a device with a resolution of 16*300 = 4800 dpi. This value significantly exceeds the resolution capabilities of conventional printing equipment and is achievable only for the highest class printing devices. Since it is impossible to simultaneously obtain high printing accuracy and preserve all the shades of the original, high-quality printing is always a compromise between accuracy and tonal balance.
When choosing print settings, in addition to general recommendations, you should take into account the features of this image. For example, for drawings with poor tones, you can painlessly reduce the size of the halftone cell. Images with a limited number of halftones are often found in poster graphics and technical drawings. To prevent coarsening of the image, which is replete with small details, you should increase the frequency of the linear raster. Typically, some types of photographs, maps, drawings, diagrams, etc. are very sensitive to loss of detail.
We give approximate values of the lineature, which is used in the production of various printed products.
- Daily newspapers are printed with lineatures ranging from 70 to 90 l pi.
- News magazines - 120 l pi.
- Illustrated magazines, depending on the quality of the images, have a lineature from 133 to 150 l pi.
- High quality, richly illustrated books - 150 l pi.
- Art catalogs and photo albums can have 200 l pi.
How do the principles of halftone screening relate to the choice of scanning resolution? In all devices of this type, there are several printed dots per pixel of the image, the combination of which forms a halftone cell. This means that the scanning resolution must be equal to the print lineature. Practice slightly corrects this logically flawless conclusion. To determine the digitization density, use the formula:
Scan resolution = Print lineature * Correction factor.
The correction factor provides a certain information reserve intended to compensate for losses when rotating rasters and resampling the image. If there are no increased requirements for print quality, then a correction factor of 1.5 is accepted. To process particularly important samples, you can set a double reserve.
From this important ratio, repeatedly tested in practice and confirmed by recognized authorities in the field computer graphics, is a discouraging conclusion for all computer extremists who are guided in their work by the principle of maximizing resolution. Even for the most important cases, when the original is being prepared for publication in a glossy magazine or a high-quality art album, it is enough to process the sample with a resolution of 200 l pi *2 = 400 dpi. The maximalist 600 dpi or the prohibitive 1200 dpi have no logical or practical basis.
Selecting the resolution for an inkjet printer
One of the most common printing devices these days are color inkjet printers. Since their entry into the market, these devices have come a long way - from the first samples, the prospects of which aroused justified skepticism among erudite technical observers and which among the user masses received the derogatory name of inkwells, to modern devices, giving photographic print quality and working at the speed of a laser printer.
As in offset printing, an inkjet printer combines several drops of dye applied to the surface of the paper per point of a digitized original. The most common in our time are inkjet printers, which print in four colors: cyan (Cyan, C), magenta Magenta, M), yellow (Yellow, Y) and black (Black, K). Some printers designed for photographic quality printing use six inks. In addition to the four main ones, they are supplied with light cyan and light magenta dyes. There are inkjet printers with even more extensive color capabilities that pre-prime the paper before printing and apply a glossy or protective layer after printing.
The first printer models used the principles of halftone screening in their classical form. Experience in operating these devices has shown the high capabilities of inkjet printing technology and its significant flexibility. Reducing the droplet size and increasing the complexity of print head control algorithms have made it possible to implement color production techniques that differ significantly from filling a halftone screen. Variable-sized droplet printing, multiple dots of ink per location, and sophisticated pseudo-mixing schemes are all technological innovations that push inkjet printers closer to the category of continuous tone printers. Leading inkjet printer manufacturers use proprietary technologies to improve print quality, the operating principles of which remain the intellectual property of their developers or are protected by patents.
Inkjet printers do not have the ideological comfort that was guaranteed by the formula for calculating resolution for devices operating according to the classical halftone screening scheme. In this case, recommendations for choosing optimal resolution scanning cannot be expressed in a laconic formula, since the inkjet printing control algorithms different manufacturers differ significantly from each other. Reliable data can be obtained based on experiments or using the recommendations of the manufacturer.
Epson offers on the market several lines of inkjet printers of different classes: office, photo printers, large-format printers and devices designed for color testing. To select the scanning resolution of originals that will be printed on semi-professional color inkjet printers and photo printers, the company advises using the “third part” rule. This means that the image should be digitized with a density that is one third of the print resolution.
For example, if 720 dpi is selected for printing, then you should scan with a resolution of 720 / 3 = 240 dpi. As the print resolution increases, this proportion should be reduced to one fourth. For example, for printing with a resolution of 1440 dpi and higher, you can set the digitization density to 1440 / 4 = 360 dpi.
For IRIS brand inkjet printers, the manufacturer Scitex recommends using the following calculation formula:
Scan resolution = Lineature * 0.75.
These are expensive devices that are used to produce color test prints in printing houses and press bureaus. We must assume that the manufacturer of this equipment, rare in our country, provides information about the printing lineature. For conventional inkjet and laser printers these data are often difficult to ascertain.
A well-known specialist in the field of computer graphics, W. Fulton, provides the following empirical rules for choosing a resolution, based on an analysis of extensive statistics on the use of computer peripherals. For inkjet and laser printers with a print resolution of 300 to 600 dpi, it is advisable to choose a digitization density of 100 to 120 dpi. If the printing device has a resolution of 600 to 720 dpi, then the density can be increased to 120 - 240 dpi. It is easy to see that these recommendations do not contradict the Epson “third part” rule, and when approaching the upper limits of the numerical ranges, they completely coincide with it.
Modern inkjet printers use very sophisticated printing algorithms in their work. They are capable of producing prints of such quality that, in visual assessment, are not inferior to photographic photographs. There is a certain numerical threshold beyond which print quality does not show a direct relationship with increasing scan resolution. Practice fully confirms this analytical conclusion. For most models of color inkjet printers, this threshold lies in the range from 240 to 300 dpi.
In online publications you can often find the statement that the scanning resolution should be an integral part of the selected print resolution. As is often the case on the WWW, this advice is provided without citing the source or author. This requirement seems justified, and several rational arguments can be given in its defense. The resolutions of modern inkjet printers form two normal number series, one of them is formed by the divisors of the number 2400, the other - 2880. For any line of printers, you can select a suitable value from the range from 240 to 300 dpi, in which the empirically found optimum resolution lies.
Important! All rules and recommendations given in this section apply to color and grayscale printing. In these modes, the tone and color of the image pixels are emulated by some regular or irregular grid of ink or toner dots that the printer applies. Printing in black and white mode works differently. Between the pixels of the image and the points of the paper there is, as mathematicians say, a one-to-one correspondence. In this mode, the printer operates at full capacity, so you should scan at the resolution you selected for printing.
Selecting the resolution for continuous tone devices
Simulating image pixels through rasterization is not the only way to convey colors and tones in printing. There are numerous printing devices, operating on the principle of continuous tone transmission (contone devices). These devices, different in their principle of operation, transmit tonal transitions and color gradations directly, without using rasters and printed dot patterns for these purposes.
The category of devices with continuous tone transfer includes sublimation and thermal wax printers, inkjet printers with variable droplet size, color copiers, film recorders, etc. Printers that output digital images directly onto traditional photographic materials are becoming increasingly popular.
Let's look at the operating principle of sublimation printers. In these devices, an inking Mylar ribbon is pressed against the paper and heated. Heated dyes, bypassing the liquid stage, pass into a gaseous state and, as a result of diffusion, penetrate into the paper coating.
Sublimation printers allow you to achieve accurate color reproduction and correctly reproduce smooth color transitions with a wide range of shades. Printers are less able to print text, straight lines, and areas of color with sharp edges. These are expensive and short-run devices that require special polyester-coated paper for printing. They are used mainly for obtaining test prints of color publications before transferring them to the printing house and for printing photographs in home photo studios.
Sublimation printers use different ink chemistries. There are printing devices with dye based on wax and its derivatives. Sometimes such printers are called thermal wax printers, which causes numerous misunderstandings, since the same name goes to printing devices built on completely different physical principles.
Solid ink printers have become widespread in short-run printing. Their operating principle is reminiscent of the well-known drip printing technology. Instead of liquid ink from inkjet printers, it uses a wax or rubber-based solid dye. A special heater melts the wax, which in a liquid state is fed into a special tank. In it, the liquid state of the dye is maintained with the help of another heater during the entire operating time of the printer. The print head pumps out a small amount of ink from the reservoir and applies it through a nozzle system to a drum, which rolls the image onto the paper. Some printer models do without an intermediate drum and transfer the dye directly to the paper. There's heat and wax involved, so it's no surprise that these devices are also called thermal wax printers.
Solid ink printers cannot create a single dot of color directly, like dye-sublimation printers. They imitate shades through a complex pattern of printed dots, i.e. they use a pseudo-mixing technique. Calculation of the scanning resolution of originals intended for printing on printers with solid ink is performed using the method of inkjet printers.
Continuous tone devices rely on completely different physical effects, but there are several features common to all printers in this class, such as low print resolution. As a rule, it does not exceed 200-400 dpi. However, the high density of applied dots and a rich color palette make it possible to obtain printed copies high level, comparable in quality to color reproductions printed at maximum resolution.
Devices with continuous tone transfer assign each pixel of the image a printed dot of the required tone and color. Therefore, scanning resolution should be calculated using the formula:
Scan Resolution = Print Resolution * Scaling Factor.
If the print resolution is closer to 300, then the digitization requirements can be slightly reduced. To calculate scanning resolution, you can use the Formula:
Scan Resolution = 0.75 x Print Resolution x Zoom Factor.
Selecting display resolution
In many situations, the final output device is the computer monitor. Thus, network publications, Internet nodes and pages, multimedia and hypermedia applications, interactive training courses and manuals, etc. are intended for viewing on the screen. Developers of such products sometimes provide the opportunity to print them, but hard copies of online and multimedia publications are usually obtained , with significant distortion and quality loss.
Computer monitors, built on the basis of a cathode ray tube or liquid crystal matrix, are fundamentally different in their operating principle from any printing device. To describe the color formation technology of printers, the subtractive four-color CMYK model is used. An adequate representation of the color of monitors is provided by the additive RGB model, the coordinates of which are red (Red, R), green (Green, G) and blue (Blue, B) colors. When displayed on the screen, no rasterization or pseudo-mixing algorithms are used. Image pixels are represented by screen dots based on a one-to-one correspondence principle, which is why monitors are classified as devices with continuous tone transmission. Computer monitors cannot boast high resolution values. Even professional-class models with extreme sizes and pixels minimum size, cannot compare in this regard with an ordinary office printer. Simple calculations show that 180 dpi is an unattainable maximum for any modern technology creating an image on the screen. If we take into account all the listed features, it becomes clear that the approach that was used for different types of printers is not suitable for calculating the screen scanning resolution.
Very often the sacramental value of 72 dpi is found as the only possible resolution for presenting an image on the screen. This advice is one of the most persistent myths in the computer world. It is repeated with amazing consistency in hundreds of printed and online publications of various levels and subjects. The most reputable resources and authors present it without the slightest attempt at critical analysis. Just like the cliché football pattern of “passing on the edge and crossing into the penalty area”, which is reproduced in thousands of game episodes, the thesis is constantly repeated in the pages of computer periodicals. Let's try to check its validity.
The basis for this recommendation is most often the resolution of the computer monitor. This number is assumed to be 72 dpi. If you digitize the original with the same density, then its screen representation will have dimensions that coincide with the original ones. From a logical point of view, this conclusion is flawless; one can only doubt the initial premise.
A typical modern 15" monitor has the following: specifications: Viewable area size is 14 inches and the width to height ratio is 4:3. Typically, when working with such a screen, 800 points are set horizontally and 600 points vertically. A simple calculation using basic knowledge from school geometry and arithmetic allows you to find the absolute width of the screen. It is equal to 4/5 of the diagonal size of the visible part of the screen, i.e. 14 * 4/5 = 11.2 inches. Now the resolution can be easily found by dividing the total number of horizontal points by its absolute length 800 / 11.2 = 71.42871, i.e. almost 72 dpi.
At first glance, everything agrees; the calculation confirms the initial assumption. Let's check monitors with other screen sizes. The initial data and calculation results are given in the following table. It shows that the true resolution of a monitor can differ significantly from the canonical 72 dpi.
If we take into account non-standard settings, for example 800 * 600 on a 21-inch screen or the relatively rare resolution of 1152 * 864, then the spread of possible resolution values will be even greater. They evenly fill the range from 40 to 165 dpi and do not demonstrate the slightest inclination towards the sacramental values of 72 or 96 dpi.
Why did the myth about the lack of alternative to these magic numbers become so widespread? The most common explanation is that the first Macintosh models had a similar resolution. In the field of graphics processing, these unpopular computers did not have a full-fledged alternative among personal computers at one time, so they founded the tradition of recalculating all images intended for viewing on the screen at 72 dpi.
There is another, more technological explanation for this phenomenon. If the resolution of the image and the monitor do not match, then the dimensions of the screen image may differ from the original ones. An original digitized at 72 dpi will appear smaller when displayed on a 100 dpi screen, while on a 60 dpi screen it will appear larger than its actual size. An example of such a situation is shown in Fig. 1.10.
Rice. 1.10. Presentation of images on screens with different resolutions. The figure shows screen images of one image displayed on monitors (from left to right) with a resolution of 96, 72 and 60 dpi
In the range of possible screen resolutions, the number 72 occupies a central position; it is located in the middle of the numerical range. This means that changing the pixel density of the monitor in any direction from this line will not entail a radical restructuring of the screen image of the document.
This circumstance is especially important for hypertext pages published on the World Wide Web, since changing the size of graphic inserts can lead to a significant modification of the document layout. Increasing the size of graphics entails the use of scrolling, a viewing technique that is unanimously condemned by all researchers in the field of engineering psychology.
Reducing the size of graphics will not lead to immediate failure of the project, since hypertext pages demonstrate higher stability with respect to this transformation. But violation of proportions and loss of relationships between individual parts of a virtual project can be prevented only through the use of special events.
It is no coincidence that the true value of monitor resolution had to be determined through calculations. This characteristic only indirectly reflects the technical properties of such devices. It is not one of the parameters that the equipment manufacturer usually indicates in technical data sheets. From the point of view of a raster image, the monitor screen has no extension, but is a matrix of pixels. For this reason, to select a reasonable scanning resolution for originals intended for display, you should first take into account the desired dimensions of the screen version of the image.
Let's look at a simple example. Let an image measuring 6*4 inches be digitized with a resolution of 100 dpi. After processing, the screen version will have a size of 6 * 100 = 600 pixels horizontally and 4 * 100 = 400 vertically. How to evaluate this array of points? This depends on the size of the screen selected to display the picture. On a 640 * 480 monitor it will fill almost the entire area, on a 1024 * 768 screen there will be significant free areas, the picture will take up almost a quarter of the screen space of 1280 * 1024.
Let's say that an image measuring 6*4 inches occupies exactly half the width of a 640 * 480 screen, i.e., has a width of 320 pixels. Then it should be digitized with a resolution of 320 / 6 = 54 dpi. If, according to the conditions of the task, the image should fill the screen with a height of 800 * 600, then it should be scanned with a resolution of 600 / 4 = 150 dpi.
So, in order to choose a rational scanning resolution of an image intended for display on a screen, you need to give a clear answer to two questions:
- What are the dimensions of the original being scanned?
- How much of the screen should the digitized image occupy?
While it is almost always possible to give a clear answer to the first question, the solution to the second problem is associated with numerous factors of uncertainty. The main one is the end user's screen size. If there is no reliable information about the category of consumers of the developed product, then it is advisable to focus on the smallest screen sizes, consisting of 640 * 480 pixels.
The considered recommendation turns out to be completely valid only in the average case, when the calculated resolution falls into the central part of a certain range of technically accessible and logically justified densities.
Let, for example, you want to turn a large image into an on-screen icon. For definiteness, we will take the original values to be 6 * 4 inches and assume that the pictogram should have a size of 42 * 28 pixels. Calculation on either side (42 / 6 = 7 dpi, 28 / 4 = 7 dpi) gives very small resolution values. It is clear that such a digitization density is completely insufficient to obtain an image of acceptable quality.
Let's consider an example that is opposite in size between the original and its screen version. Let's scan a small image (0.5 * 0.5 inches) and want to get a large image (1024 * 1024). Such an original must be processed with a resolution of 2048 dpi, which obviously exceeds the optical resolution of any mid-class scanner.
These extreme examples are located on the boundaries of the notorious “average case” into which most of the situations encountered in practice “fit”. For them, apparently the best way out will use the resampling technique. If the calculated resolution is outside the acceptable range, then you should digitize the original with a density that guarantees sufficient quality of the screen version, and then use the Photoshop editor to set the dimensions and resolution that solve the problem. All necessary technical means provides the Image Size command (see Figure 1.6). Working with this command is discussed in detail in the section “Scaling and sampling in Photoshop.”
On a note! No speculative thoughts and speculative calculations can replace experiments. Is it better to scan the original at 90 dpi or digitize it at 270 dpi and then reduce the size of the screen version by a third? You can only choose one of the options through experience.
Isn’t it too cumbersome technology being proposed to solve such a relatively simple problem? The described technique and the principle based on the magic number 72 dpi correlate with each other approximately like a forecast and a prediction. To find out the weather for the next day, you can calculate a system of differential equations or simply rely on the state of your grandfather's sciatica. In many cases, both methods will give the same results. To ensure the smooth operation of the airport, grandfather’s testimony will be considered unconvincing, and the integration of differential equations for choosing a uniform is an obviously redundant procedure.
If your sheet spans more than one page, you can print headings or row and column labels (also called print headings) on each page. For example, when printing large sheets with complex layouts, you might want to repeat the first row of column headings on all pages.
Note: Team Print on every page will not be available if the work is performed in cell editing mode, a diagram is selected on the same sheet, or a printer is not installed.
Further actions
Notes:
Disclaimer regarding machine translation. This article has been translated using computer system without human intervention. Microsoft offers these machine translations to help users who don't know in English, read materials about products, services and Microsoft technologies. Since the article was translated using machine translation, it may contain lexical, syntax and grammatical errors.
Please use the English version of this article, found at , as a reference. You and other Microsoft community members can improve this article by using the Community Translation Framework (CTF). Simply hover your mouse over a sentence in an article and select IMPROVE TRANSLATION from the CTF widget. For more information about CTF, click . By using CTF, you agree to our
Until now, we have devoted all the articles in the “Office Rules” series to working with text, graphics, and tables on the monitor screen. Unfortunately, many users forget that a document on a monitor screen does not always look the same as on a sheet of paper. On the screen, you can not pay attention to the font size, adjusting the size of the letters by scale, not using margins, not numbering pages (after all, the page number is displayed in the status bar). However, if the document is sent for printing, all these nuances become very important. If a document has no margins or is smaller than required, the printer will refuse to print. If page numbers are not included, you can spend a lot of time trying to put the sheets in order. There can be a lot of such problems if you don’t take care of such little things in advance, even before the document is printed. So today we'll look at some settings to keep in mind before you print your document.
First, let's look at the paper. What paper are you going to print on? If it is a regular A4 size there should be no problem, however if the paper is a non-standard size you may need to change some settings.
Sometimes it is convenient to print a document by changing the paper orientation from portrait to landscape (Fig. 1). For example, when the document contains wide tables or graphic elements that are better placed in a row. In this case, before printing, in the Page Setup dialog box, on the Margins tab, change the page position in the Orientation frame. Below you will see what the document will look like. If you need to change the paper orientation of not the entire document, but only part of it, before calling the Page Setup window, place the cursor at the place in the document starting from which you want to change the orientation. Now open the Page Setup window and in the Preview settings group, select the Apply to this point forward line. In the same settings window, you can select the paper size (Paper) on which to print. As a rule, they print on standard size sheets - A4, A3, A5, etc., however, if the paper size is non-standard, the length and width must be set manually in the appropriate boxes.
If you need to change the paper size of not the entire document, but only part of it, before calling the Page Setup window, place the cursor at the place in the document starting from which you want to change the size. Now open the Page Setup window, go to the Paper Size tab and in the Preview settings group select the Apply to this point forward line. Before printing a document, pay attention to the font size. However, much will depend on how you prepare the document for printing. Let us draw your attention to some features.
On the screen, the font may appear large, because many users deliberately set the scale larger. On printing, it may appear too small.
Think also about document margins. Document margins are the distance between the edge of the page and the text. Accordingly, the larger the field, the less text fits on the page, and vice versa. Headers, notes, and graphic objects can be located in the margins. The margin size can be changed manually using the vertical and horizontal rulers, as well as in the Page Setup window. Their digital values can be entered on the Margins tab. Usually their size is set in the range from one to three centimeters. When working with certain types of documents (for example, legal contracts), it is sometimes necessary to number not only pages, but also lines. Microsoft Word makes it possible to automatically number lines. Run the command File > Page Setup and go to the Paper Source tab (Layout), then click on the Line Numbering button. In the Line Numbers dialog box, check the box next to Add Line Numbering. Specify from which number you want to start numbering in the Start At field and which line numbers will be printed in the Count By field. Lines can be numbered at a certain interval (for example, 5). In the Num-bering settings group, you need to select the numbering type. It can be continuous throughout the document (Continuous), start from a new section (Restart Each Section), or from new page(Restart Each Page).
You can see how the document will look before printing by going to Print Layout mode or Print Preview mode. To view a document before printing, Microsoft Word has a built-in Print Preview function. In Preview mode, the user can see one or more pages of the document in full on the screen. This mode helps determine how the document will look when printed. It is especially useful if the document contains graphic objects, other embedded objects, fields, etc. To switch to this mode, use the Preview button on the Standard toolbar or the CTRL+F2 key combination. In Preview mode, a preview panel appears instead of the standard toolbars. With its help, you can change the number of pages displayed, install or remove vertical and horizontal scroll bars, and enlarge individual parts of the page. There is also a Shrink to Fit button in the preview pane. If during the viewing process it turns out that some two or three lines have ended up on a separate page, use this button. The program will make some adjustments to the formatting, which will be almost invisible to the eye (for example, it will make the font a little smaller), and the document will look more aesthetically pleasing. 
When the document is completely prepared for printing, let's turn to the printer settings. To open the Print dialog box, run the command File > Print or use the hotkey combination CTRL+P, then select the printer in the dialog box that appears (Fig. 2). If you need to configure printer settings, do not use the Print button on the Standard toolbar. When you click the button, the Print dialog box will not appear and the document will immediately begin printing.
If the printer you want is not in the Name list, you must install a driver for it. To do this, follow the normal Windows installation procedure (for different versions it may differ).
You can set print settings for each printer. To do this, use the Properties button. Each device has its own settings for installation. Typically, here you can specify the feeding method, paper orientation and size, graphics mode, etc. In addition to selecting a device for printing, in the Print window you can set parameters such as page numbers to be printed. You can print all pages, just the current page, a selected section, or specify the page numbers that need to be printed.
The page numbers to be printed are separated by "," (for non-sequential pages) and "-" (for sequential pages). You can also specify the number of copies to be printed in the Print window. The number is set manually. If the Collate checkbox is checked, the printer will print sets of documents. The next parameter is Scale. This group of settings specifies the number of document pages that need to be printed on one sheet. This number can be from one to 16. In this case, the pages are reduced to the appropriate size. This option can be used to see how multiple pages of a large document will fit together. By specifying the range of pages to print, you can print all pages, only even pages, or only odd pages.
If the document is large enough and you only need to print a small part of it, you can specify this in the print settings. To print part of a document, select the required fragment, open the Print dialog box and in the Pages settings group, check the Selection line. 
At the bottom of the Print dialog box is the Options button. It gives access to the Print dialog box, which sets some Extra options. The Print dialog box with additional print settings can also be accessed by running the Tools > Options command and selecting the Print tab. In the Printing Options settings group, you can set the automatic conversion of documents formatted for the A4 standard to the Letter standard. The latter is used in the USA. If the Draft Output checkbox is checked, printing will be faster, but some formatting elements will be lost, and if the Background Printing option is enabled, the document will be printed more slowly, but the user will be able to work with other files (Fig. .3).
In the Include With documents settings group, you can set the printing of some document controls: notes, hidden text, field codes, document information (on a separate page at the end of the document). You can also specify the paper feed method in the Print dialog box. Usually the mode is set to Use printer settings. Some printing options can be set simultaneously in both the printer settings and the Page Setup and Print dialog boxes. If different values are entered for the same parameters, those entered in the Microsoft Word dialog boxes take precedence.
And finally, a few recommendations regarding possible problems arising during printing. If empty frames are printed instead of graphic objects, check that the Drawing Objects checkbox is selected in the Print dialog box (Tools > Options > Print tab). To print graphic objects, the checkbox must be checked. If you are printing field codes instead of graphical objects, check that the Field Codes checkbox is selected in the Print dialog box (Tools > Options > Print tab). To print graphic objects, the checkbox must be unchecked. If fonts look different on screen than in print, check to see if you are using True Type fonts. Only these fonts look the same both on the screen and on the sheet. You can check if the font you are using is a True Type font by doing the following: Expand the Font list on the Formatting toolbar. An icon with two T's will appear next to True Type fonts.
You can also see if the font you selected is a True Type font by running Format > Font and selecting the desired font from the list. A description will appear at the bottom of the window. If you are using display fonts that are not True Type fonts, try to find the most appropriate printer font.
Now that you know these little tricks, you can start printing. We hope you don't have any problems!
Sergey Bondarenko, Marina Dvorakovskaya,