7 Reasons Why EPS Files Are So Large

As anyone who has worked with EPS files can attest, uploading, downloading, or sharing them, can often become a laborious, time-consuming task. This is because it is not unusual for EPS files to be quite large. For instance, an EPS file created through Adobe Photoshop can exceed 16 megabytes in size for a 4.25 x 6.25 image rendered in a CMYK color scheme (which is common for digital offset printing).

Whether you are a graphic designer by trade, earn your living in the marketing department, or simply need something professionally printed, chances are good that if your tasks involve digital artwork in any form, then you work with EPS files and have likely had to deal with their immense sizes.

And since you need to understand the beast in order to tame it, here are 7 reasons why EPS files are so large.

Why Are EPS Files So Large?

Why are EPS (Encapsulated PostScript) files so large? The simple answer is that they are specially formatted for the creation, sharing, and outputting, of graphics in any number of forms, utilizing the PostScript programming language platform.

Whether they contain text, graphics, images, or any combination thereof, EPS files allow digital content that is created on professional graphics programs to be accessed downstream and output on devices like printers, printing presses, and the like.

But this does not tell the entire story, so here are 7 specific reasons why EPS files are so large.

1. Overly Complex Artwork Paths Can Make EPS Files Larger

A common culprit responsible for making EPS files larger than they need to be is the use of excessive anchor points. If you ever played connect-the-dots as a child, imagine the dots being anchor points and the completed drawing as a digitally-created image and you have a good idea of how the concept of an artwork path works.

The problem that can occur is when there are an excessive number of anchor points tied to an image. In the end, this overabundance becomes a classic case of being too much of a good thing that can have these undesired results:

  • Needlessly increasing the EPS file size
  • Making edits more difficult and laborious
  • Slowing down proper displaying and printing of the image

Fortunately, there is a straightforward fix for eliminating extraneous anchor points by utilizing built-in features like Simplify Path, Image Trace, and Variable Width.

2. Check for Unused Palette Items

Professional-grade graphics applications are packed with powerful features and all the tools that an artist or designer could ever imagine needing. But sometimes these helpful amenities can get in the way and add unnecessary heft to an EPS file size. For instance, tucked away within the file formatting can be palette items like:

  • Brushes
  • Symbols
  • Graphic Styles
  • Swatches

Unused palette items can be removed from digital artwork, and accordingly, EPS file sizes can be reduced. In Adobe Illustrator, for instance, unused brushes, swatches, and the like, can be deleted from a single palette, or from all palettes associated with a particular file.

3. Hidden Raster Images Can Inflate EPS File Sizes

Another circumstance that can result in inflated EPS file sizes is when a raster image (i.e., an image composed of colored pixels) such as a bitmap illustration, is used as a reference tool and then forgotten when the work has been completed. This can result in unexpectedly large file size, not to mention the unnecessary frustration of hunting down the cause.

As with many other causes of cumbersome file sizes, there is a straightforward solution, and in the case of hidden raster images, an EPS file can be cleansed by:

  • Unlocking all objects and layers
  • Showing all hidden objects and layers
  • Selecting the raster image in question and removing it from the EPS file

Reducing EPS file sizes by removing unwanted raster images is a matter of following a few simple steps; the challenge is recognizing that a hidden or forgotten object is weighing down an EPS file in the first place.

4. Repetitive Elements Can Increase an EPS File Size

With the powerful design capabilities offered by professional graphics programs, EPS files can be quite complex and elaborate, and this can potentially lead to issues relating to file size. For instance, if digital artwork contains repetitive elements, such as a cloud-filled sky, the cumulative effect of these individual components can bog down an EPS file and cause its size to balloon.

Fortunately, there is a solution: repetitive elements can be grouped together and saved as a vector symbol, in essence consolidating multiple components into a single graphics entity and thereby reducing an EPS file’s size significantly.

5. Excessive Steps in an Object Blend

One of the tools that are often utilized in working with graphic design applications is the manipulation of different colors. Where the desired effect is migrating between colors, in order to achieve the smoothest transition possible, more steps in the blend are needed (think of them as gradients shifting incrementally from one color to another).

There comes a point, however, where the number of steps (gradients) in transitioning from one color to another, does not produce any appreciable benefit. In other words, the added degree of smoothness in shifting between colors is so imperceptible as to be negligible, and meanwhile, the price to be paid for these unnecessary object blend steps is larger file size.

6. Embedded Raster Images Can Cause EPS Files Sizes to Balloon

Graphic designers across the globe have embraced working with the EPS file format because of the great versatility it affords. For instance, EPS formatting is vector-based but still allows for raster images to be embedded into working files. The problem with this practice, however, is that placing a raster image into a file can cause its size to balloon, particularly if it is high-resolution.

One solution is to use a linked image rather than an embedded one and the potential savings in terms of file size is potentially enormous.

7. Unnecessary Image Attributes Can Weigh Down an EPS File

In a similar fashion, embedded raster images in an EPS file can have attributes that are not only unneeded but also make the file size larger than is necessary. Here are some ways to reduce the file size of an EPS file by modifying embedded raster images:

  • Cropping a raster image to only that portion that is actually needed can drastically reduce the file size
  • Even unnecessary background colors can be eliminated to minimize file size
  • Reducing the resolution of a raster image is another effective strategy

There may be times when linking to an image may not be feasible and therefore embedding a raster image is the only option. But there are ways to minimize an embedded raster image’s effect on an EPS file’s size.

Final Thoughts

For decades, the EPS file format has been instrumental to the productivity of graphic designers and digital artists everywhere. With powerful tools at their fingertips, it is easy to see why the EPS format has been synonymous with graphic design for so many years. And while large file sizes can be challenging to deal with, a little bit of software savviness is all it takes to reduce them to workable levels.