Dot Gain Settings : Bringing the match between digital and production prints closer

Simulating the effects of the production printing process in AVA


A dot gain is used to simulate the effects of the production printing process in AVA. It is designed to adjust the view of the design on screen and thus the print you get from your digital studio printer, to make them look more like the results you get in production. This helps to ensure that an accurate design separation is created.


Dot Gains can be created manually if you know what data to use, or you can extract one from the measurements of an ECI 2002 target when using AVA Production Colour Management.

A dot gain curve must be set up in order to reproduce the effect of ink loss or gain in production. For example, when printing from a cylinder, you may find that an 80% area of tone looks exactly the same as a 100% area of tone. To compensate for this, you would set the 80% tone level to 100% in the dot gain window. This would darken the design on screen, thus simulating the finished output from the press.

A dot gain can also be used to simulate the loss in strength of the ink printed off the cylinder. For example, the layer colour can be set to 100% tone and the design can be toned down to 80%, showing the final print from the press. 

Dot gain curves are applied in the Dot Gain Settings . They come in two forms:

  • Global dot gain - which affects all layers in all designs in AVA
  • Individual dot gains - which can be applied to any active layers in the design, and will override the Global Dot Gain if one is set
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Note: Dot gains do not change the pixel data in the file, they only change the appearance of tones within it.


Creating a Dot Gain via a Tone DB

  1. Print set of step wedges with different densities and angles. Make sure they got your cylinders well. We recommend printing several copies in case any get contaminated in the finishes process.

    This is just an example. You can add more densities and angles if needed.

  1. Once printed, finish the prints. For example, steam and wash, bake etc.
  2. Read the step wedges into a new colour file in ColourSys, including the substrate (000) and naming each colour the correspondent density value, e.g. 000, 001, 002, 004,006, 008… etc.

  3. In ColourSys, go to the ToneDB Menu and select New ToneDB. The following window will open:

  4. In the Tone Steps section, type in the steps used in the step wedges.

  5. Drag the substrate colour from the colour file to the substrate space on the ToneDB Window.



  6. Go to the ToneDB Menu and select Import Colours from Document.
  7. From the drop down menu which opens, select the relevant colour file. The number of colours included in the selected colour file will be listed at the top of the Tone DB window:



  8. From the Tone DB Menu, select Optimise Tone DB. The curve will change to reflect how the tones print in production. This is your Dot Gain.

  9. Hold down ^ (control key)  on your keyboard and click on the curve and select Save from the contextual menu and name the dot gain appropriately.
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Setting the dot gain in AVA

The Dot Gain preference opens a pane with the title Global Dot Gain. Any changes made in this window will affect the view of your design, but will not affect the actual data on any of the layers, so you can still use them for engraving.

  1. Go to AVA Menu > Settings and click Dot Gain.
  2. Adjust the curve. If you have 'Shift click to add gamma nodes' ticked in the General Settings , you will need to hold down the shift key to add a point to the curve.

  3. If you wish to label the dot gain curve you have created, making it easier to identify in the Layers Palette, hold down ^ (control key) and click in the window and select Information from the contextual menu. Enter a relevant name for your global dot gain curve.


  4. Again hold down ^ (control key) and click in the pane and choose Save from the contextual menu in order to save this curve for use elsewhere (such as another AVA workstation). Name the dot gain curve and save it.
  5. Ensure View Menu > Use Dot Gain is checked to be able to see the effect of the global dot gain in the design.

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Note: To be able to view which dot gain you have set, choose AVA Menu > Settings and select the Layer Palette button. Switch on the Dot Gains option in the Layer Text tab of this window. The dot gain information will be displayed next to the colour blocks in the Layer Palette.



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Individual layer dot gains

Individual dot gains must be used if you are going to be mixing a number of different cylinders that may print differently in production.

When, for example, a company has been using one dot gain for several years and then changes to a new one, all of the legacy designs will print out incorrectly when using the new curve as they have not been engraved with it.

It is also of benefit to people who engrave different layer types with different curves. For example, much of your tone work may be engraved on one setting, but some of your fine tone work could be on another.

You can also use it in situations where there is a different dot gain for each pitch and angle (as with CMYK layers). Many companies use their CAD system for a variety of customers and as such need to use a specific dot gain for particular customers.

Once set, a layer’s dot gain remains with the layer until it is cleared. This happens even if the layer is split and merged into another design. Each dot gain contains information to help identify it.

Creating an individual Dot Gain for a specific layer

  1. Activate the relevant layer and go to Layer Menu > Dot Gain…
  2. Click the + button in the top left hand side of the dot gain pane. This will put a line on the pane, known as a dot gain curve, ready for you to adjust.
  3. Hold down ^ (control key) and click within the Got Gain Window to reveal a contextual menu.


  4. Select Information from the menu and enter the desired name for the individual dot gain. Enter relevant information to identify the curve, such as Light Cyan curve.
  5. Adjust the dot gain accordingly.
  6. Hold down ^ (control key) again and click in the gamma pane and choose Save from the contextual menu in order to save this curve for use elsewhere (such as another design). Name the dot gain curve and save it.
How to load an existing dot gain into a layer

You may receive a dot gain from a production site, which is specific to the tonal breakdown of their inks. To load this into an existing layer:

  1. Activate the relevant layer
  2. Select Layer Menu > Dot Gain…
  3. Click the Load button at the top right corner of the pane and choose the relevant dot gain file from the window.

In the example below, a special dot gain has been loaded to the cyan layer. The magenta, yellow and black layers are all using the global dot gain set in the Dot Gain Settings .

Clearing individual dot gains

  • Activate the relevant layers in the Layers Palette
  • Go the the Layer Menu and select Dot Gain...
  • In the window which opens click on the '-' button to remove the dot gain curve

Any curve information will be completely removed and the dot gain name in the Layers window will default to say Global. The dot gain pane will appear empty.

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Note: The Use Dot Gain option in the View Menu should normally be on all the time (showing a tick next to the menu item), you can switch it off and on to see the effect your Dot Gain is having on the design.

The Status Window displays a warning if a global dot gain is set. Clicking on the dot gain warning button in the Status Window will open the Dot Gain Settings to allow you to change it or remove it, if necessary.




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