How can you troubleshoot color issues on a digital press?

Apart from these cases, it is very important to always use a calibrated monitor, a monitor whose colors are exactly the same as the printing machine, and it is better to do a color test before printing a large volume.

Check your inks how long has it been since you rebuild your inks? Any contamination within the inks? How old is the blanket?did you run a gray balance and check where you are with the inks using the spectrum

IMO the best practice would be to supply a customer-approved colour proof to the supplier, ideally sanctioned under GMG or a similar workflow, and ask for a wet proof to be sent back, or even better, a press-pass if time location allows for it.

Spent a good part of my life in Printing (Sheetfed Offset, Flexo, Dry Offset, Web Offset, Roto and Rotary Screen). In Prepress we dedicated our lives to controlling all issues, color, trap, dot gain, impositions, take off bars, color bars, impression guages, creep, glue flaps, bleeds, finishing and potential press problems or print issues by producing the best film, plate or digital plate we all could muster so the press operators could concentrate on ink, paper, running to color, press checks, customer OK and their press schedule (no small feat). Everyone in the plant that touched production was a professional. Now come full circle with Digital Presses and I read this post. Someone needs to rethink the question or rethink the process.

When you notice an obvious defect such as a mark or color variation across the web, it could be mechanical or blanket related depending on which print technology is being used, i.e., inkjet or electrophotography. It could even be related to the primer with which the substrate is coated. Inspect the anilox roll for defects or buildup and check if the correct primer is being used. Ensure that the printer has been calibrated. Once it is determined that the printer is in an acceptable calibrated state, check if the appropriate color management has been applied. If everything is in order, step outside of automatic color management and manually iterate the color values by adjusting your artwork colors to visually match the master color sample.

Make calibration second nature when running color critical jobs. I would also add that importing/exporting color profiles can work wonders in getting color dialed in. When in doubt, just bypass all conversions possible and let the file be your guide!

A lot of modern printers have built in color calibration but it's up to the operators to actually use it. Also don't forget that the calibration is usually specific to the material being used so it may need to be run again when switching substrates, especially if the material hasn't been loaded into the machine for extended amount of time.

In my experience it also depends on when the last time the inks were rebuild and calibrated. I use to do this every week a color was rebuild and calibrated to narrow down color issues when it arises.The file maybe build wrong need 4colors but it was build with 7 colors.

Yes, you have to run make ready on a digital press too! As an operator it's easy to focus on image positioning during make ready but using these sheets to check and adjust color is a best practice in my book.

Use color profiles load them directly in the RIP so the same curves are applied all accross. Digital presses can accurately print a broad spectrum of colors and spot colors aka Pantone colors.

Some color settings in design software can be balanced, so you can partially solve these problems by using some tools, and then calibrating the monitor is in the next step.