1. Bi-directional alignment
a. In diagnostics mode fill in the correct paper thickness of the used paper.
b. Perform alignments in diagnostics mode
c. Make a test print in USER mode with the correct media thickness.
(Don’t print in DIAGNOSTICS mode. This is not reliable and may result in unwanted side effects like noisy prints etc…)
d. Make a test print in USER mode with ‘media thickness + 20μm’
e. Make a test print in USER mode with ‘media thickness + 40μm’
f. Set the media thickness in the firmware User Type or the RIP to the best result of previous 3 tests.
2. Step Adjust correction for production modes (low amount of passes)
The micro-adjust pattern is moving the media in very small amounts. This method is not ideal to adjust the media feed of print modes that use large feeds (for instance 2 scan print modes).
The ultimate method is by printing an image, and use the length that you measure to calculate the correct step.
Print a 1000mm image. This is accurate up to 0,01% and makes sure that the effect of swing bars or other take up mechanisms and large passes is taken into account.
How to do it?
a. Print an image with your software using a step correction of 0% (or 100% depending on the RIP’s driver).
The image length (feeding direction) is the theoretical length (in this case: 1000mm).
Mount your media on the take-up roll for correct feed behavior!
b. Measure the real length of your image (in this case : 1006 mm)
c. Calculate the step adjust percentage and insert this in your driver or in the User Type in the firmware.
In our case: ((1000 - 1006)/1000)*100 = - 0,60%
Note:
the obtained step correction will most likely be around 0.25% lower using this method compared to the Micro Adjust method.
3. Drop usage
The visibility of the overlapping zone between heads is very dependent on the usage of the small drop.
If the overlapping zone is still visible after transfer to your textile, best practice is to eliminate the small drop of a certain dot family.
Example of the overlapping zone with Small drops (Left) and without Small drops (Right)
For instance: when using 360x720, 2 scans, variable dot VSD3 make a profile only using the M and L drop.
There are basically 2 methods to obtain this depending on whether the RIP has the ability to exclude the S drop or not.
Note: never test this without making a dedicated profile (or at least linearization and ink limits), since the calibration has a big influence on the dot distribution.
Printing without a profile may result in wrong judgements.
a. Limiting in RIP
Most RIPs are able to manipulate the drop usage/distribution.
b. Drop Mapping
When your RIP is not able to adjust the dot distribution the firmware has a function that changes all S drops to M drops when data comes in.
It can be enabled here:
> DIAGNOSTICS mode > Parameter > Update > Drop Mapping
Note: available from FMW 1.07E or higher.