As a maker you often get requests to deliver high resolution publicity material like photographs and logos but also posters and flyers. With all the different sizes, files and formats it can be hard to keep track and define what is what. Below you find a list with definitions including some key rules, do’s and don’ts.
Important! The images that you use for your benefit must be original and free of copyright.
In some countries it is a legal requirement that people in photos must have signed a release on file. Keep this in mind, especially if using images shot in public places.
It is standard courtesy to credit the photographer. However avoid embedding the photographer's credit inside the image itself. For publicity purposes it is better to state the photo credit in the file name, and inside the textual part of your press package or e-mail communication, with a kind request to credit the photographer in all published instances.
Give your photographs / artwork descriptive file names including your name, the piece title and the photo credits. Avoid using symbols and non-latin characters in a file name. They can render differently on different computers.
For example: Pina Bausch - Vollmond - photo by John Smith.jpg
Landscape vs portrait
Make sure to add both landscape (horizontal) and portrait (vertical) pictures to your media-kit. The different communication channels like websites, magazines, brochures etc. might require different formats. Give your partners something to choose from.
Image size and resolution
You probably have or will at some point encounter a request for images that are "large enough for print". But, a layperson justifiably wonders, what does that mean?
Well, every digital image consists of a certain number of dots, which we call pixels. Let's begin with that.
How to tell how many pixels your image has?
On a Mac:
1. Open your image in Preview
2. Go to “Tools” in the top menu
3. Open “Inspector”
1. Right-click the image
2. Select properties
Now you've done the first step.
Confusion happens when an image which appears to be relatively large on screen, turns out not to be large enough to print. How is that possible?
Digital images posess one more property, called resolution. Resolution defines how densely packed the pixels are inside the image. The higher the resolution, the finer the detail.
Resolution is most commonly expressed as a dots per inch value, or dpi.
A resolution of 72dpi is enough for screen viewing. However the standard resolution for print is 300 dpi.
This means that in order to achieve the same size that you see on screen, you are going to need a lot more pixels in the print.
Feel free to use this calculator in order to figure out how large your image will be when converted to a resolution of 300 dpi:
Bear in mind:
If your image is 1200 x 600 px, it can not be made larger without loss of quality.
A large image can always be sized down, but a small one cannot be sized up. This is why you should always keep originals, in their largest possible size.
Image color formats: CMYK vs RGB
CMYK stands for cyan, magenta, yellow and key (black). These are the colours of ink that are used in print. Any artwork that is being prepared for print must be converted to CMYK mode. This can be done by your designer or print shop however.
RGB stands for red, green and blue. This is the colour scheme used for viewing images on screen. An image in CMYK mode might not show correctly in web browsers.
Image colour modes can be changed using photo editing software such as Adobe Photoshop, Elements, Lightroom or similar.
Sending your images
High resolution pictures are great for print work. They are also heavy digital documents. Most mail servers limit the largest size of file that can be attached in an e-mail. This is why, when sending large documents (larger than 10MB), it is advisable to do it through an external service such as wetransfer or upload them to a cloud service such as Dropbox or Google Drive, and share the links with the intended persons.
By doing so you will ensure your e-mail doesn't get stuck on the server, and also avoid clogging up people's inboxes.
File formats: when to use what
We can identity a lot of different file formats, especially when working with different computer programs. Here we give you a list of information that might be of use for your practice.
- JPEG / JPG
A great format for both digital artwork and print work, can be opened by every device. Jpg is the best format for storing photographs in, when you need to share them with others, especially on the web.
Note: when saving a .jpg file in an image editing program, there is an option to compress the image. Image compression produces a smaller sized file (fewer kilobytes), but also reduces image quality. Avoid using jpg image compression if the images are intended for print, because compression can visibly degrade image quality.
Pdf files make sure your documents and graphics are displayed correctly online. They are not used for images alone, but for layouts that contain text and images. They keep your design together, are easy to view, download or print. They can be viewed using most modern electronic device and computers' native software, as well as in web browsers.
You can save Microsoft Word files as pdf, however keep in mind that unlike .doc files, pdf files cannot be edited.
A pdf file is also the file format requested by printers when you are producing print work, however those files are heavy in size and have special markings on them. If you are working with a designer, ask them to make a special lower-resolution pdf version of your promo materials, for screen viewing.
If you have access to Adobe Acrobat, you can use it to reduce the file size yourself, or, alternatively, use a free online service to reduce the pdf file size on your own.
A png file is for web-use only. Unlike jpg, it can be transparent. This comes in handy for standalone artwork like logos that need to be placed on top another image.
Avoid saving photographs as .png files though, since the file size tends to be much larger than .jpg. Use it strictly for graphics like logos, when you need a transparent background, no loss of quality and to use it strictly on the web.
GIF is an image format used for storing short animation sequences, which are to be viewed in a web browser. Do not save photographs as gif, because its colour range is limited and you will lose image quality. Although just like png, gif can have a transparent background, it degrades image quality too much to be optimal for storing logos. Is not recommended for any other purpose than animation.
Tiff files are known for their extremely high quality. They are primarily used for photography and optimal for print. Be careful though, as these are typically very large files, larger than jpg. Do not use for web graphics. Most web browsers can not open tiff files.
This is a Photoshop document. This file is great when the files still need editing in Photoshop, and the person you are sending them to has Photoshop on their computer. Never send PSD files in your final press package.
EPS is a vector file format. Vectors are used for drawn graphics, such as logos, and never for photographs. The main advantage of vector graphics is that they can be scaled indefinitely without loss of quality. (Remember, this is not true of bitmap file types like .jpg, .png, .tiff, etc., they are always limited by their total number of pixels and any enlargment beyond it causes blurring and pixelisation. )
Eps is the most universal vector format, and can be opened with a wide range of professional and semi-professional graphic programs.
A professional designer will always supply you with a logo in vector format, and this is the preferred format for all logos that need to be printed.
Also worth noting: a photograph can never be converted to a vector.
AI stands for Adobe Illustrator and is another vector-based format. Keep in mind, unlike EPS, a person must have the correct version of Adobe Illustrator installed in order to open this type of file. AI is good to have if the file is meant to still be edited, but in general it is better to send finished vector graphics in EPS format.
RAW is a professional digital camera image format, and comes with a range of different file extensions, for example: .DNG, .CRW, .DCR etc, depending on the camera that took it. It is a heavy, uncompressed file format which allows high image quality editing in professional software like Adobe Photoshop and similar. Opening a RAW file may require special software and plugins installed. This is why you should never send RAW files in media packages. Always convert them to JPG or TIFF first.