Published: 3/29/2003
Author: Jason Beck

Recently, a handful of people told me that they use Fireworks for compressing images because it produces smaller images with better quality than Photoshop. I tried it out, and my first impression was that what I was told was true. I offered this suggestion to someone else, who immediately created an example page that seemed to contradict my initial impression. I decided that I needed to take a more scientific approach to find out for sure which program really was better. Before I ran the test, I also learned that JPEG is, in itself, a specification for compression, and in theory, all applications that follow the specification should behave the same. However, applications are given the freedom within that specification to use an arbitrary scale. Because of this, compression level of 50 in one application might not correspond to compression level 50 of another, because it's not a universal JPEG compression level, but simply a number specific to each application.

The Test

For the test, I attempted to remove subjectivity where possible, and keep a fixed environment, so the only variables are the applications compression engines. First, I took 10 uncompressed digital photographs - 17.3MB TIFFs. I opened each in Photoshop, resized them to 640x481, and saved them as .PSD files. Then I took all the files, and opened them in Photoshop and Fireworks. In this stage, the only processing I did was save out compressed images. This process should result in useable test data.

The Results

25kb For this test, I ran the images through each applications compression engine, choosing the highest level of compression (the lowest number), that resulted in an image over 25kb. In hindsight, I probably should have used the highest number resulting in an image under 25kb, but the end result should be approximately the same. It's difficult to see any difference between the images, but I personally prefer the quality of the photos compressed in Photoshop.

Quality 60 In this test, I used the quality setting of 60 in each application to produce compressed images. My first conclusion is that these numbers do not correspond to each other. However, if you don't plan on magnifying the images, the quality of the images created by Fireworks is usually satisfactory, with file sizes often three times smaller than the ones created by Photoshop.

Balanced For this test, I attempted to create small files that did not appear to sacrifice quality at 2x magnification. We see a mix of results here, as sometimes the Photoshop files are smaller, and sometimes the Fireworks files are smaller.

Quality 60 2x This time, we take a look at the impact of opening compressed files, resizing them, and recompressing them. Here, it's quite clear that the smaller files created by Fireworks carry much lower image quality.

Quality 30 Using quality setting of 30 in each application, we see how different they handle compression. Photoshop produces larger files with acceptable image quality, while Fireworks produces much smaller files, with very poor image quality.

30/60 Match Here, we can compare the Photoshop images at level 30 compared to the Fireworks images at level 60. This is a close match, but once again, I think I prefer Photoshop.

30/67 Match Here, we can compare the Photoshop images at level 30 compared to the Fireworks images at level 67. Overall, smaller images and better quality with Photoshop.

The Conclusion

In the end, it seems like both applications can do a fairly equal job of compressing images. However, Photoshop's entire range of compression falls within the acceptable range, while most of Fireworks range is generally unusable. My final test showed Photoshop in a good light, showing better quality with, on average, smaller images. I prefer Photoshop for giving me the ability to fine tune my compression to my taste. In a few cases, I was not able to go below 25kb using Photoshop to compress a 640x481 image, so if you need smaller images, and are willing to sacrifice some image quality, you may prefer Fireworks.