PrinterCal contains advanced profile options which can provide better printed results, particularly when printing none separated artwork such as RGB images that are out of gamut.
When you select Save ICC Profile from the File Menu of Printer Cal, you can select which type of profile you want to save. You have the following options; Best for Separate Designs, Best for Image, Best for Flat Colour and Custom. This article focuses on the Best for Images option.
In the example above, the image on the left is using the default profile option in Printer Cal (Best for Separated files) the image on the right is using the 'Best for Images' option, as you can see in this example you get better contrast and colour saturation with this option set
The colour contained within images is handled in a different way to those contained within separated artwork, and therefore, if you predominantly print images, we strongly advise you to use the Best for Images option when building your profiles. You can of course save different versions of the profile from the same set of measurements, and do some test prints to see what works best for your designs.
You will get more of a difference / advantage between the different profile options if your printer has a smaller colour gamut to start with or the designs you are printing are out of gamut.
How to save a Best for Image profile
- Open your printer profile measurements into PrinterCal (this is the .printercal file which you saved at the end of reading in the profile target).
- Go to File Menu > Save ICC Profile, and in the window which opens, select Best for Images from the Profile drop down menu.
- Press OK and save with an appropriate name.
- Once the profile has built, set this in the Profile section of the AVA CMS Controller as your new printer profile.
Within the Advanced options, the following settings are applied when using the 'Best for Image' option.
You can adjust the setting above further, for example you may prefer the look of your files with the 'Smooth Separation' option checked, but take care to note what settings you used so you can achieve the same results with new profiles at a later date.
What are the disadvantages of using an ICC profile set to Best for Images?
The main disadvantage over the 'Best for Separated Designs' is a loss of accuracy, particularly for colours closer to the edges of the colour gamut. So for example if you are printing a spot separated design with measured colours or PANTONE®®s the output will be more accurate using the 'Best for Separated Designs' option.
Further image adjustments
To improve the look of images further you could use the Colour Correction Layer in AVA. In the example below you can see that the original image (top image) is a little too dark using the 'Best for Image' profile, so I used the Colour Correction Layer to make the shadows a little lighter and I also increased the colour saturation a little to make my image look a little more vibrant, see bottom image.
Another option would be to try using Black Point Compensation, this can have a similar effect, but can result in the image looked more washed out that it should, see related articles for more information on this.
We recommend you run some test prints with this new profile, and if you have any concerns over the printed files, please contact AVA Technical Support for advise on how to improve your prints further and check your profile measurements.
AVA 中的黑点补偿对图像配置文件的黑点应用偏移，使其与输出配置文件对齐。这可以帮助您在图像中获得更多色调运动，特别是在黑暗区域，以便您保留阴影中的细节。
在显示图像和通过配置文件分离时，AVA 可以使用 BPC。 AVA 中使用嵌入式 ICC 配置文件的任何函数都可以使用 BPC。
注意：BPC 可用于除绝对色度之外的所有渲染意图，因为此意图模式会尝试尽可能准确地再现图像中的颜色。
使用 BPC 分离
通过配置文件进行分离会应用当前的配置文件设置（渲染意图和 BPC）。因此，请确保您使用的配置文件设置正确，以获得准确的分离。
- 要设置或更改配置文件设置，请将 ICC 配置文件加载到 CMYK 图层上。通过按住控制键并单击图层面板中的配置文件图标来设置正确的设置。
- 保存配置文件。然后，您可以使用该配置文件来分离其他设计。
- 从 CMYK 图层中删除配置文件。
- 使用多种分离技术之一来分离您的设计，例如“分离菜单”中的“使用轮廓...”。
注意：查看分离结果时，最好关闭 BPC。
采用 BPC 的配置文件将与配置文件选择器分离方法一起使用，但在用作目标配置文件时，生成的 delta-E 差异将无法提供判断最佳配置文件的准确方法。这是因为 BPC 故意扭曲图像中的颜色，增加 delta-E 差异，而配置文件选择器会寻找最接近的匹配。同样的原因也适用于比较函数。
推荐设置：
- 扫描 RGB 图像- 使用相对色度意图和黑点补偿
- 分离到 CMYK - 使用相对比色而不使用 BPC，除非这会产生不好的结果，在这种情况下尝试 BPC 进行分离。始终在没有 BPC 的情况下查看 CMYK 图像，否则您可能会得到非常不切实际的最终打印效果
- 查看 CMYK - 关闭 BPC 并使用相对或绝对色度渲染意图
Rendering intents determine how colours are mapped when moving images from one colour space to another. They have a particular impact on colours which are outside the gamut of the destination colour space, be that your desktop printer or production. Using the correct rendering intent for the job is necessary in order to obtain the best results from images with embedded profiles.
To change the selected rendering intent, hold down the control key and click on the profile icon in the Layers Palette. A contextual menu appears.
Select the Rendering Intent you want to use for the selected layer or image and the change of Rendering Intent will be applied.
Note: Not all profiles implement all four Rendering Intents. All profiles will have the two Colourimetric intents but the Perceptual and Saturation intents may be missing. If you use a rendering intent with a profile that doesn’t implement it, AVA will use Relative Colourimetric intent instead.
Any changes made to profiles which are attached to layers are recorded in the History Window, therefore you can go back if the change was not necessary. To further improve the reproduction of images, you may also wish to apply Black Point Compensation.
There are four Rendering Intent modes:
Absolute Colourimetric rendering intent
AVA will reproduce the colours in the image as closely as possible to the original. All colours in the image that are within the gamut of the output device (monitor or printer) will be reproduced exactly. If the profile white point differs from the current substrate colour, white areas on the image may end up darker than the substrate or light tones may be clipped. Some types of profile (such as most scanner, digital camera and monitor profiles) do not work well in absolute mode and give a strong colour cast to the image.
Absolute Colorimetric intent is recommended for proofing CMYK profiles where you want the proof to match the original image.
Relative Colourimetric rendering intent
This mode is similar to Absolute Colorimetric mode except that the white point of the profile is scaled to that of the substrate. The effect is that ‘white’ areas of the image will be the same colour as the substrate. All of the colours in the image are modified to compensate for the differences between the profile white point and the substrate colour.
Relative Colorimetric mode would be appropriate for a design with a mix of CMYK process layers and spot colours. Using Relative Colorimetric mode ensures that the white areas in the CMYK images will match the substrate colour.
Perceptual rendering intent
In Perceptual mode, the colours in the image are modified to produce an attractive result. Colour accuracy may be sacrificed as a result. The white point in Perceptual mode is treated in a similar manner to Relative Colorimetric mode.
Perceptual mode is appropriate for applications where you have an image and want to generate a nice looking separation from it (such as for scanned images or digital photographs). It may also be useful when importing CMYK images from other applications.
Saturation rendering intent
This mode is intended for the reproduction of business graphics (like graphs), where you want the brightest, most saturated colours possible. Saturation intent is not generally used in colour managed workflows.
Note: Adobe® Photoshop®™ normally uses either Relative Colorimetric or Perceptual intent, so if you are importing graphics from a Photoshop®™ based workflow and want the colours to match you should use the appropriate mode.
All profiles have a default rendering intent. AVA will use this intent when the profile is first assigned to a layer.
The use of profiles on CMYK and RGB images is essential for the creation of colour stable images which can be viewed at a later date on the same or different CAD station with the knowledge that the colours will be as consistent as they were the day they were created.
These days, profiles can be embedded within documents rather than relying on a single global system profile to be used for all files. These profiles can also be set on individual colourways or individual layers. Once set, they are automatically saved within AVA, PDF and JPEG files and are restored when the files are reopened.
The Layers Palette shows a small multi-coloured profile icon when a profile has been assigned to a layer.
If a profile is not set on any layers the software uses the setting from the Overprinting Settings window. However, if a profile is set the overprinting option Use ICC profile on CMYK/RGB Image is overridden.
In AVA, you can apply ICC profiles from the desktop to a file, from a file to another file or from within the same file, simply by dragging and dropping individual ICC profiles next to each layer. When you hover over the ICC profile icon, a + symbol appears which indicates that you can drop the profile there.
You can also set a profile by holding down the control key and clicking on the profile icon to access its contextual menu and selecting Load Profile.
The profile is only set for the current colourway but you can apply this profile to other colourways, if required, by selecting Apply to all colourways in the contextual menu. If a new colourway is created, the profile is automatically duplicated. However, if you hold down the option key and click the “+” button when creating a new colourway, no profile will be set.
Internal efficiencies ensure that only a single copy of each profile is saved within the file. This means that your files will not become too large as a result of having many colourways using the same profile.
Once set, a help tag showing the profile’s name will be shown when you hover over the profile icon in the Layers Palette.
Embedded profiles can be removed from layers by dragging them to the bin. you can also remove a profile by holding down the control key and clicking on the profile icon in the Layers Palette to access its contextual menu and selecting Clear Profile.
It is not possible to save an ICC profile by dragging it from a file to the desktop. Use the Save Profile command from the contextual menu instead.