Mutoh 1204 not printing gradients correctly

[AdamsG]

Hey,

Im trying to print a design with a dark gray to light gray gradient in it. When it prints out it don't look right, I have some stickers with this design leftover from the last time I did this job, and they don't match. The dark gray and light gray are both lighter than they should be, and in the middle of the gradient theres almost a shade of red in there.

Has anyone had this problem or know how I might fix it?

TIA

 

[heyskull]

Greys are a pig to hit on any CMYK printer and even harder when they are graduated.
If this doesn't match your previous most likely you haven't used the same print profile as before.
Also are you using the same ink and is your nozzle test as good as it was when last printed?
Even a couple nozzles out can drastically change greys.

I have just printed a van wrap and a 20'x20' roller shutter door for a client of ours on our 1604 and the vast majority of it was grey.
I found that the only profile that would look acceptable with no visible red or green was to print at the machines maximum of 1440x1440.
If you lower the print quality more reds or greens appear.

SC

 

[AdamsG]

Hey Thanks for the help.

Im using the same ink as the previous print. Not sure about the profile tho, although I never change that too much so I would think its the same one. My nozzle check looks pretty good, Im missing just a couple spots in the red, otherwise its good. I went to a 1440 x 1440 profile, and it gets rid of the reddish tint, but still not matching my previous print yet.

 

[scott dunacn]

Hey Thanks for the help.

Im using the same ink as the previous print. Not sure about the profile tho, although I never change that too much so I would think its the same one. My nozzle check looks pretty good, Im missing just a couple spots in the red, otherwise its good. I went to a 1440 x 1440 profile, and it gets rid of the reddish tint, but still not matching my previous print yet.

i have the same problem have you fixed it if you have how did you

 

[Jim Hancock]

I would suggest this is likely a linearization issue. The linearization is can be off in part of the density curve, resulting in some densities being gray and other densities having a color shift. Have your profiles re-linearized (re-calibrated) and see if that fixes your issue.

 

[bob]

Grays are always a problem on a CMYK printer because grays are printed using CMYK instead of just K. That being the case it's ridiculously easy for a gray to drift off to magenta or green or whatever for any reason or no reason at all. You can diddle your profile if that's what gets you off and you might or might not move the output towards plain old vanilla gray. Or set things up such that only K is used although the output would be kind of thin. Otherwise, live with it and try to talk people out of doing anything with grays.