Poster Printing Design Basics

Written by UPrinting    ●    Updated on September 15, 2023

When it comes to bringing your creative concepts to life, printing plays a crucial role in doing justice to your designs. Nothing beats seeing your vision in print. To ensure your custom posters truly shine and are ultimately effective in attracting people’s attention, it's essential to set the correct resolution, colors, and format. In this comprehensive guide on how to prepare your poster for printing, we’ll walk you through the process of creating creative posters from scratch, whether it’s for a movie, concert, trade show, or any event.

Resolution, Colors, and Format

No matter how brilliant your creative ideas are, achieving the desired outcome heavily relies on proper printing techniques. Image resolution, colors, and format play a crucial role in the quality and overall impact of a poster. Understanding and taking advantage of these elements are essential for creating visually appealing and professional-looking posters.

• • Resolution: Resolution refers to the level of detail and clarity in an image and is measured in dots per inch (DPI) or pixels per inch (PPI). In poster making, resolution directly affects the sharpness and crispness of the final print. A higher resolution ensures better image quality and prevents pixelation or blurriness when the poster is printed in larger sizes.
• • Colors: Colors evoke emotions, convey messages, and grab attention. In poster making, the selecting and managing of colors is crucial for creating a visually engaging design. Two important color models used in digital design are RGB (Red, Green, Blue) and CMYK (Cyan, Magenta, Yellow, Key/Black). RGB is used for screen display, while CMYK is the preferred color mode for printing. Converting colors to CMYK ensures accurate representation and prevents color variations or discrepancies when the artwork is printed.
• • Format: The format of a poster determines its dimensions, orientation, and aspect ratio. Choosing the right format is essential for achieving a balanced and visually pleasing composition. Common poster formats include portrait (vertical), landscape (horizontal), or square. Each format has its own advantages and may be influenced by the content and purpose of the poster. Considering the format from the start allows for effective use of space and proper placement of text, images, and other design elements.

Camera Resolution for Poster Printing

Understanding the relationship between camera resolution and printing quality is essential. For the uninitiated, digital pictures are made up of tiny colored dots called pixels. The more dots in the picture, the higher the resolution; therefore, the larger pictures you can print. The maximum resolution of a digital camera is usually measured in millions of pixels called megapixels (MP).

For print, we always recommend using your camera’s highest possible resolution. It’s better to have a file that’s too big versus one that’s too small and pixelated or grainy. Printers are still largely measuring print resolution in dots per inch (DPI); a dot is essentially a pixel. An old, low-end fax machine might be 200 dots per inch; a laser printer might be 1,200 dots per inch. 300 dots per inch is usually considered an acceptable resolution for printing. For print products, it’s always important to have high-quality images, but it becomes even more crucial with displays designed to be seen up close, such as 18” x 24” posters.

Working With CMYK and RGB

CMYK and RGB are two different color models used in design, and understanding their differences is crucial for printing.

• • CMYK (Cyan, Magenta, Yellow, Key/Black): CMYK is a subtractive color model used in printing. It uses a combination of four primary colors—cyan, magenta, yellow, and key (black)—to create a wide range of colors. In this model, colors are created by subtracting light from white paper. The more color is added, the darker the resulting shade. CMYK is ideal for printed materials because it accurately represents the colors that can be produced with ink on paper. It is commonly used in professional printing processes, such as offset printing.
• • RGB (Red, Green, Blue): RGB is an additive color model used for electronic displays, such as computer screens, televisions, and mobile devices. It combines three primary colors—red, green, and blue—to produce a wide spectrum of colors. In this model, colors are created by adding different intensities of light. The combination of red, green, and blue at maximum intensity creates white, while absence of light creates black. RGB is used in digital design and online platforms because electronic devices emit light to display colors.

When preparing designs for printing, it is important to convert the colors from RGB to CMYK. This conversion ensures that the colors on the printed poster closely match the colors on the screen. RGB colors often appear brighter and more vibrant on screens than they do in print. By converting to CMYK, you can achieve more accurate color representation in the final printed product.

Here is an example of the RGB image converted to CMYK. Notice how they differ in color:

If you prefer to convert the files on your own, here’s a brief guide on how you can change the color mode in various design programs:

Photoshop

1. In starting a new project, select CMYK for the color mode. If you’re working with an existing file, select the following menu options: Image > Mode > MYK.
2. Check how your files are going to look by turning on the “CMYK preview” mode.
3. Do not make change color modes repeatedly because every time you switch, you lose image quality and multiple shifts will reflect on the clarity of your final design.

Illustrator

1. Select File >Document color mode > CMYK color.
2. Stick to CMYK and Grayscale color models.
3. When working with Pantone colors, make sure that you convert them into CMYK mode or leave them as spot colors to be able to print spot color inks.

Quark Express

1. Use the following menu options: Edit > Edit Colors > Show Colors in Use > Highlight Color and click Edit. Work around the “Edit Colors” dialog box.
2. Change model to CMYK and deselect Spot color. Use only CMYK model and Pantone coated model ink definitions.
3. Control carefully the colors to be separated into CMYK and which should remain as spot colors. It’s quite challenging to convert colors in Quark.

Be mindful that not all RGB colors can be converted to CMYK. This is because there are RGB colors that are out of the CMYK array. When this happens, the closest CMYK shade to that specific RGB color is used. (Make sure you give the CMYK converted file to your trusted printing company as these services normally don’t cover color conversion.)

Focus on File Formats

In poster printing, there are two main file types used: bitmap and vector images.

• • Bitmap images, also known as raster images, are made up of a grid of pixels. Each pixel contains specific color information, resulting in a detailed representation of an image. Bitmap images are resolution-dependent, meaning they have a fixed number of pixels and can lose quality when scaled or enlarged. Examples of bitmap image file formats include JPEG, PNG, and TIFF.
• • Vector images are created using mathematical formulas and geometric shapes. Unlike bitmap images, vectors are resolution-independent and can be scaled or resized without losing quality. They are ideal for designs that require scalability, such as logos or illustrations. Common vector file formats include AI, EPS, and PDF.

Choosing the Right Paper Finish for Posters

The choice of finish significantly impacts the overall appearance of your posters. The right coat will help define the overall appearance of your prints. Posters are commonly glossy to make the design colors vibrant; the luster makes prints attractive even from afar. However, matte is a good choice if you want to use an unconventional finish for your print products.

High Gloss offers the widest color range for vibrant colors. It makes all colors pop but placement will be crucial since the shiny finish will have glare from bright lighting. Semi-Gloss is the most popular print finish for posters. It still offers vibrant colors similar to high-gloss with reduced glare. It’s also less likely to be smudged. Matte has the least sheen among the three print coatings. It offers an elegant finish that’s best for text-heavy poster designs.

For more information on custom poster printing, feel free to call our friendly customer support at 1-888-888-4211 or click the Live Chat Assistance button at the top of the page.

You can watch this video on How to Make Custom Posters: