Introduction to Profile Prism
Making Your Own Printer Profiles
Making Better Printer Profiles
One question we often get asked is "can you really make printer profiles more accurate than the manufacturer"? Most printers ship with ICC profiles for various papers produced by the printer manufacturer. If those profiles don't install with the driver, they can often be found in the support section of the manufacturer's website. So can Profile Prism really beat the profiles developed by the company who designed your printer?
In a word: absolutely!
(see writeup below image)
The following are notes applicable to the above comparison:
- The above is a printer/profile evaluation test image that can be found here (link to the TIFF image is at the bottom of the page).
- The top image is the original which was converted from the original ProPhoto color space to sRGB for web viewing.
- Scans of prints (bottom images) were acquired using a profiled scanner and the scans were properly converted to sRGB color space (again for web viewing).
- The two bottom images represent scans of prints made with the manufacturer supplied printer/paper profile (left) and a Profile Prism v8.4 generated profile (right).
- Printer is an Epson R1900 printing on Ultra Premium Luster paper using manufacturer inks.
- Some compromises exist in viewing scans of prints online due to the fact that some of the actual print is beyond the gamut of sRGB (strawberries for example).
- But the above serves as a reasonable comparison for our purposes.
Notes on results:
- The obvious brown cast in the gray scales on the manufacturer profile (left) is easily visible on the print. Profile Prism print (right) looks completely neutral WRT grays.
- Notice better (and more accurate) shadow detail on the Profile Prism print.
- Skin tones are much more accurate on Profile Prism print.
- Stone arches at top much too dark/saturated in manufacturer profile (more obvious in the actual print than the scan).
- Strawberries are too dark and saturated in manufacturer profile.
- Profile Prism renders the strawberries with a near perfect match in the actual print: their color is a little beyond sRGB so they appear more faded in the above scan.
- Some saturated greens shift yellow in the manufacturer profile (example: middle green gradient lower left). No problem with Profile Prism.
- Shadow detail is lost completely on the circuit board (extreme upper left of image) in the manufacturer profile. Again no problem for Profile Prism.
- Manufacturer profile also loses shadow detail in the grayscale image in the middle. Profile Prism not only renders proper gray, but with all the shadow detail.
Again, the above is meant to demonstrate some of the actual areas where Profile Prism excels. With the actual prints in hand, comparing to a profiled monitor, the Profile Prism print is actually even closer to the original image than what is pictured above. This is due to some compromises being made when scaling color gamuts so we can show you these examples in your web browser: some of the original colors (in ProPhoto) as well as some of those that can be printed, are beyond the range of what we can show you (with 100% accuracy) here.. So while the above is about as close as we can get to showing you what you can get from Profile Prism, the results are even better (more accurate) than what we can show you on the web!
Suffice it to say: yes, Profile Prism can generate (and has in every case we've encountered) better profiles than the ones that ship with your printer/driver or can be found on the manufacturer's website!
So Profile Prism isn't just for people running third party inks or papers.
About Profile Prism
Profile Prism is software that allows monitor calibration and can generate ICC profiles for digital cameras, scanners, and printers using an IT8 reference target. Resulting color profiles may be used in any ICC aware application such as Qimage Pro, Adobe PhotoShop, Corel PhotoPaint, and many others. The software is designed for a PC running any 32 bit Windows operating system, however, it can be run on a Mac running Virtual PC. In addition, since the ICC profiles generated by Profile Prism are 100% compliant with ICC specs, the profiles themselves may be used on any platform (PC, Mac, etc.).
Included with Purchase of Profile Prism
CD with latest version of software
Quick start software installation guide
Reflective glossy 5x7 IT8 color target with 288 color patches
Comprehensive help for calibrating monitors and profiling cameras, scanners, and printers
Sturdy cardboard envelope for storage of color target
Free tech support and access to latest upgrades via the web for one year
Free uploads/downloads from our profile sharing area (FTP site) for one year*
* Only ICC profiles generated by Profile Prism may be shared, and may only be shared with other registered Profile Prism users via the FTP site.
Order replacement color targets online for $24.95 each (includes shipping/handling)
Renew your access to upgrades and profile sharing area for $15 per year
About ICC Profiles and Profiling Tools
Most digital imaging devices such as cameras, scanners, monitors, and printers reproduce an image by breaking the image down into millions of tiny light points called pixels or dots. By mixing specific amounts of red, green, and blue to produce specific colors at each of those locations, an image is formed. Although a device might specify that some location in your image is bright yellow by mixing high intensity red and high intensity green, the actual shade of yellow that is reproduced will be different on different devices. Since the specific color reproduced by a device depends on the exact "shade" of the primaries used (red/green/blue for cameras and scanners and yellow/magenta/cyan/black for printers), we must analyze and discover what shades of red, green, and blue or yellow, magenta, cyan, and black are used by the device first, before we can understand what colors we get when we mix these primaries at different levels. For example, if a device indicates that a color is maximum intensity yellow (255,255,0 in 24 bit color terms), we need to know what shades of red, green, and blue are used in the mixing and how they "react" when mixed.
ICC profiles give us a way to accurately describe the above aspects of how color is recorded by devices so that we can guarantee a reasonable level of accuracy when displaying/printing images from a camera or scanner. You can think of the full spectrum of color that the eye can see in terms of a map similar to the one below.
To be able to ensure accurate color from one device to another, we must be able to map colors from the specifications used by the input device (camera or scanner) to the specifications used on the output device (monitor or printer). An ICC profile specifies how each of the 16.7 million colors captured in your [24 bit] image are located on the map of visible colors. To be able to "convert" from the colors used by your camera/scanner to those used by your monitor or printer, we have to specify both a profile for the camera/scanner as well as a profile for the output device (monitor/printer). ICC profiling is therefore like specifying "from" and "to" coordinates on a map. Colors can then be converted "from" your camera/scanner "to" the color used by your monitor/printer. As can be illustrated with the map analogy, you must always have a "from" and "to" point on your map to be able to specify how to get from point A to point B. Without an accurate profile for both your input and output device, there is little hope of ensuring truly accurate color because there is no way to give "directions" to ICC aware software about how to get from the color of your camera/scanner to that of your monitor or printer.
Profile Prism, like most profiling tools, uses a calibrated color target and complex regression analysis to discover the characteristics of your camera, scanner, and printer and produce ICC profiles that describe how these devices "see" color. Profile Prism does not currently offer a method for profiling monitors since accurate monitor profiling cannot be accomplished without special hardware (a monitor colorimeter) that attaches to the monitor and measures its performance. Profile Prism does offer monitor "calibration" to ensure that the monitor is operating as designed and under optimal settings. Most calibrated PC monitors respond well when used with the sRGB color space profile, so sRGB can be used for the monitor profile (after calibration) for relatively accurate color. The only way to ensure a very high level of monitor color accuracy is to use the (relatively expensive) option of monitor profiling tools that use a colorimeter to measure monitor color response. Visual calibration or "gamma" tools other than that found in Profile Prism also work fine for the purpose of monitor calibration, however, some of these tools actually save an ICC profile based on selection of monitor phosphor type or monitor brand. Since the color response of phosphors in an arbitrary monitor vary within a single brand of monitor and can even vary with the age of the monitor, selection of phosphor type or monitor brand is almost always based on nothing more than a guess by the user. As a result, the ancillary monitor profiles generated by visual calibration tools is often less accurate than simply using the sRGB standard combined with a good monitor calibration!
For a more in depth discussion of color management and ICC profiling in general, see our ICC profiling page at http://www.ddisoftware.com/qimage/icc.htm.
ICC Profiling Tools
Profile Prism, like other profiling tools, uses information that it obtains from the capture of the included color target to discover the color characteristics of a device and create a profile that describes those characteristics. The quality of the image capture or scan of the color target(s) is critical in the process of profile creation. Unlike other profiling packages that make little mention of the importance of the capture process, Profile Prism gives you the software tools to evaluate your image capture of the color targets and gives detailed instructions describing what to look for at each step in the image capture and profile development process, including things that can go wrong and how to correct them. As a result, Profile Prism and its documentation may appear to be more complex than some profilers, but attention to detail is critical when developing profiles and (unlike other software), Profile Prism gives you the information you need to be able to generate high quality profiles without falling victim to problems that can result from not fully understanding profile development or simply not having the tools to evaluate results along the way. While other profiling software may attempt to make the job look easier by "hiding" the intricacies of profile development or ignoring major issues that can easily be addressed by the user, Profile Prism provides instructions and methods that allow users to produce ICC profiles that easily exceed the quality of other tools simply by supplying the needed documentation and software tools to do the job right the first time.
Once you are familiar with methods for creating accurate profiles, the process normally runs very smoothly and requires little effort. It is important, however, to follow instructions closely until you are comfortable with all the variables involved in creating accurate profiles. Remember that the more meticulous you are about your procedures, the more accurate your profiles will be.
One final issue that is important to understand about ICC profiling is that it cannot do the impossible. Many people start out looking for software that can make their prints look exactly like images on screen. Unfortunately, printers have a much narrower color "gamut" (coverage of the visible colors) than monitors, so there are a large number of colors that display on screen which are physically impossible to reproduce on a printer! Printers perform very poorly on bright blues for example and many shades of blue that are reproducible on your monitor are far out of reach for your printer. For this reason, compromises are often made by profiling software to get acceptable appearance of color on two devices that are not well matched. ICC profiles can do two important things here though, even when dealing with colors that are out of range on a device: (1) profiles will generally make the best compromise so that color errors are not "clumped" in any one region and will therefore produce the most acceptable color overall and (2) profiles will ensure consistent color from image to image.
With the above in mind, feel free to browse the full help file for Profile Prism. It is available online so that you can get an idea of how to operate the software and the process involved before purchasing. Any questions not covered here can be sent to our tech support at firstname.lastname@example.org.