Image Processing: Getting Started
Image Processing steps are used to include in a PMM images edits, DTG presets and DTF hybrid screening options.
These steps are typically performed in Pre-press using tools such as Illustrator or Photoshop. By incorporating these options into the PMM, the process can be automated, as the image processing steps are applied automatically whenever a file is processed with the selected PMM.
By default, an Auto white option is created as part of a DTF PMM and the Auto white behavior depends on what White percentage, White generation and choke has been applied during initial profile creation.
Important note: If "Auto White" is enabled in the PMM, Any adjustments made in Editor, Layout, Workflow, will not have take effect, as the Auto White from the PMM will be used. To enable control of White generation via these tools or custom Image Processing steps, you can remove the "Auto White" option (Shape and Choke).
Select "Auto
White" and click the "–" symbol to remove it. Before making any
changes to a PMM, it's recommended to duplicate it first.
To add custom Image Processing steps leave the "Auto White" option in place and when right-clicking “Auto White,” a
menu will appear with the option to “Add New Image Step.” An Image Step can
include an image edit, DTG preset, or a sample document with embedded changes.
If there's no Image Processing step defined you can also right click the Print Settings menu to access the "Add New Image Step" menu.
Image Processing: Image Edit
First time opening Image Edits
will show an empty list.
Typical DTF Image edits are:
Increase Saturation to make
images “pop”.
Increase in Contrast to prepare
for t-shirt color knock out.
Example:
Duplicate the existing PMM so
that new edits are not affecting the original PMM.
To duplicate select the PMM Mode
and select the duplicate icon at the bottom of the window and provide a new
print mode name.
First time opening Image Edits
will show an empty list.
Using Editor, make sure to select the DTF printer and print mode then proceed to create the desired
Image Edits.
Open an image into Editor (Image is used to preview the image edits).
Select the loaded image and select from the Image menu the desired edit option.
When replacing the printed black
with shirt black (or any other shirt color) it's beneficial to increase the
contrast (Levels).
Another
common adjustment is increasing Saturation to make the colors pop.
Once the desired image edits have
been performed, the edits can be saved as an image
script.
And after saving the Image Edit Script the following confirmation will appear.
Now re-open Calibrator and select the duplicated PMM.
The saved Image Script can be
selected by right clicking the Image Processing section in the PMM and
selecting Image Edits.
Once loaded the Image Edits like
Levels and Hue/Saturation will show with their respective behaviors.
Any file which is being processed by this PMM will automatically contrast, saturation adjusted and still using the default Auto White behavior.
Another Image Processing step could be the DTG/DTF specific steps like removing shirt color. More details in the following article:
DTG or DTF separations
A heavier knockout works effectively by making the black or any other shirt color area transparent, allowing the shirt's color to show through:
- DTF 45 Chroma 90 Tolerance (Black Shirt)
This approach is also suitable for colored shirts.
Once the DTG preset has been created it can be selected and added like any other processing step:
Other way to import (multiple) image steps is to apply them in Editor to an image and then save that image with all the steps being part of it.
This will allow Image Edits, DTG Presets and the DTF Halftone Screening Preset to be applied to the PMM.
Image Processing: DTF Halftone Screening
To create a halftone screen, open the
Editor. Under the "Extra" pull-down menu, select "DTF
Screening." This will open the Halftone setup dialog.
Leave the Channel selection set to "White“.
For Shape, select "Round," as it is the most commonly used option.
A typical setting is a 22-degree Angle.
The Frequency should be determined by evaluating the
PMM White Test Chart and the LPI Test, with a common frequency being 25 LPI.
Choke, this is a positive value in millimeters, a common White Choke
for DTF printing is around 0.1 to 0.25 mm inward from the edge of the colored
layer.
- 0.12 mm choke (0.004 inches): For fine details or smaller designs
- 0.15–0.2 mm choke (0.006–0.008
inches): For standard prints, providing a
good balance between opacity and edge cleanliness
- 0.25 mm choke (0.01 inches): For larger, less detailed designs where
there’s more tolerance for alignment shifts.
Testing for optimal results with your
setup is ideal, since the right choke can vary based on factors like ink type,
transfer film, and printer resolution.
The Input
Range feature allows users to control the
sensitivity of the alpha transparency (using a bump curve) and avoid halftone
screening in highlight areas.
A 2% to
98% bump curve range focuses opacity adjustments on
mid-level transparencies while leaving the lightest (near 0%) and darkest (near
100%) areas mostly unchanged.
This boosts mid-range transparency for more
visibility without affecting the extremes, preserving delicate fades and solid
areas for smooth gradients and balanced opacity.
Main purpose is to avoid
halftone screening in skin tone areas (95%-99% range).
Once the desired screening is set and been applied, the Editor displays a preview of the
applied screening.
When the Output panel is selected, and the mouse pointer
hovers over the preview, the CMYK+W values are shown.
Each channel can be
individually previewed by toggling the eye icon to enable or disable the
preview.
If DTF screening changes have to be made, use the Edit > Undo option to revert back
to the previous setting(s) and re-apply with new DTF Screening Settings.
If a DTG shirt color knockout (DTG
Preset) is applied, Editor also simulates the background.
The background color can be adjusted
under the View > Background menu
White background with black knock out
applied.
Same image with black knockout but with Black simulated background
Applying the Image Processing Steps: Sample Document
Final step is to save the Image Processing Steps like the DTF Screening as aur file (Special PrintFactory file format).
File > Save As, name the file with the Image Processing Steps applied for example:
Once saved the preset can be applied to the PMM by selecting the Sample Document.
In Calibrator, select the PMM (Mode), expand the so that more details are visible, then right click the Printer Settings, select Add new Image Step.
As Type select, Sample Document, and browse to the location the aur file has been saved to.
Once applied the Image Processing step will be added to the PMM.
Here's an example of a DTG Preset (black knock out) combined with the DTF Screening.