When is comes to logos and photos for print projects, there are a lot of misconceptions. A little knowledge can go a long way, often toward more confusion. Let’s see if I can clear things up. I am not going for techno-babble here, just trying to clarify the concepts for non-designers. In the past, I have tried to explain resolution to co-workers/salespeople, clients and even a graphic design intern often with the same result: ‘too many letters… eyes glazing over… only hearing blah, blah, blah…’ I have worked hard to make this painless, and, now, I have a visual aid! Can’t go wrong with a visual aid.
Let’s limit this conversation to logos. When you need to provide a logo for a print project, the best choice is and Illustrator file (.ai or .eps) — end of story. A graphic designer can convert an Illustrator file into any size or format they need. In a perfect world, that’s all you need to know, but we live in the real world, so more information is in order.
It has happened at every design/marketing company for whom I have had the pleasure to work. A company logo is requested for a print project (an ad, a sign, a banner), and the logo that the designer receives is too small or poor quality for print. It usually comes from the company web site. Using any image off the web for a print project is almost always a bad idea. Sure, it looks great on your computer screen. It is meant to look good on screen, but once it is blown up to the right size at the right resolution for print, it won’t look so good.
Sometimes, a high resolution jpeg or tiff is acceptable. (There are other options, but opening that can of worms is probably a bad idea.) Occasionally, the person making the request will ask for a jpeg or tiff. It is worthwhile to ask the right people, probably a marketing person, to make sure you are providing the right file type that will represent your company properly. Sometimes, there isn’t anyone else to ask. In that case, you still need more information.
Many people use the term dpi (dots per inch) to mean the same thing as ppi (pixels per inch). For the sake of what we are concerned with here, it is the same thing. If someone requests a logo at 300dpi or ppi, they are referring to the resolution of the photo file. The higher the number, the more dense the pixels (or “dots”) are in the photo. The ppi is only half the resolution story.
File size matters. If the logo is 300ppi, but the file is only 1/4 inch tall, it will still look bad when you blow it up the size you need. If I am going to print a 4″x6″ photo, the file needs to be 300ppi when it is 4″x6″, or 300ppi at “final resolution.” If you take a photo off of your digital camera, in many cases it will be 72ppi, but it is 42″x32″. So, if I change the photo to the resolution that I want, 300ppi, while constraining the proportions, the photo will be about 8″x10″. I hope I didn’t lose you. If one takes that photo off the camera and changes the size to 4×6, but leaves the ppi at 72, the resolution of that photo has been reduced. Once it is saved that way, you can’t go back.
Let’s take a look at some visuals. (Click on the photo to see it full size.) The first logo below (a) is straight off of my web site. It is a jpeg (a image format file) 72ppi (pixels per inch) at about 3″x1″. This is typical resolution for most web use.
The second logo (b) is the same logo, but I changed it to 300 ppi, constraining the proportions. Now, it is 300ppi but only about 3/4″ by 1/4 “. The third logo (c) is the same, but blown up 300%. You can see the loss of quality as the logo is blown up. If the intention is to put this logo on a big banner, it will need to be blown up twelve times or more than the original.
The last illustration is the same logo (the O in “works”) blown way up to 1200%. You can see the pixels or little square that make up the picture. The photos from your digital camera (any photo format files, e.g. jpeg, tiff, gif, etc.) are made up of the same little squares.
The two boxes on the right illustrate what happens if you try to “increase” the resolution without constraining the proportions. The fact is, you can not increase the resolution. These days lots of people have photo editing software. Many people have discovered that they can change the number in the “pixels/inch” box. The problem is that the ppi is directly linked to the picture size. (Pixels per inch and file size determine resolution.) You can not increase one without proportionately decreasing the other. If one just increases the number of pixel per inch, the result is illustrated in the box on the lower right. The number pixels increase, but it will not effect the quality. If the photo on top is 100ppi and you change the number to 400ppi, each square (pixel) will be divided into 4 squares (pixels), but the photo quality will not visually change. The picture will take up more room on the hard drive. You have made it larger, but not better.
This misconception of increasing resolution is reinforced by TV and movies like CSI. All that stuff we have seen on the crime dramas where they take a crummy photo from a surveillance camera and “sharpen it up” so you can see the bad guy’s face or a license plate number — that’s bunk. Some software will average the pixels that are next to each other and create new pixels, but it won’t be accurate information. You can’t create information where there is none. There are some tricks that can help the cause, but there is only so much that can be done.
When in doubt, it is best to send your company logo as an Illustrator file. Illustrator uses vectors, not pixels. An Illustrator file can also be converted to a Photoshop image format, if necessary, or it can be blown up without loosing quality. Illustrator files are not universally better than Photoshop files, just different file types for different purposes. When it comes to your company logo, Illustrator is my preference.
(If the designer that created your company logo did not provide an Illustrator file to you, shame on them! There are exceptions where other file types will work…can…worms…not going there.)