Xerox 770 - Black type looks good but not grayscale image

[Darkstarter]

I have a simple form with a small 10% grayscale image behind some of the black type.
This is a 3-up duplexed job on 8.5x11. When I run wide the 10% screen looks worse on the far side of the output. All the grayscale image looks darker around the edges and lighter or missing toward the center of those images. All the 100% black images are very sharp and smooth.

I'm using 80# uncoated digital cover. Fuser is almost brand new, just had developer replaced and just replaced drums. Technician just calibrated the 770.

 

[arossetti]

10% screen is very difficult to have look consistent throughout the page. Your eye notices color/hue differences more in pastels and halftones. My guess is that your 770 is within spec (6 deltaE76 within a page) but visually it looks really off. I'm afraid that there is not a whole lot you can do to solve that with a digital printer.

You can ask the tech to adjust the inboard/outboard color shift but I wouldn't expect perfect output with that design.

 

[Darkstarter]

Thank you for mentioning "inboard/outboard color shift". I am new to digital printing (35 years in offset).
There have been a few other jobs I've run and noticed a multiple-up image look different on one
side of the sheet than the other side. I will mention this to the tech. At this point he thinks it's a fuser problem.

 

[cosmo]

convert the 10% to cmyk?

 

[mattbeals]

converting the 10% tint to cmyk will give you problems with gray balance.

 

[jotterpinky]

I agree with Matt, you'll have problems with gray balance but depending on the condition of your drums the 4-color gray will probably look smoother. You'll need to tweak it quite a bit to get a "neutral" gray and you probably will have problems with a more "pinkish" or "greenish" gray on one side of the sheet (inboard vs outboard) which unfortunately is just something you have to deal with on this level of machine.