Need Help Completely stumped Roland spot grey

[antant77]

Hello, I'm kind of having trouble printing a Roland spot color grey...

brand new head and dampers, nozzle test is perfect, bi-directional test is perfect, feed test is perfect, encoder strip cleaned... no issues with the printer or printing any other color...

When I print an RGB grey the print is flawless except the fact that it's more green than grey... I picked a Roland spot color grey and convert spot color checked in versaworks and it does print the correct shade of grey using only K black but no matter what I try there's whiteish vertical bands whenever I use Roland spot color grey, I've googled and watched videos on the Roland site on how to print grey, but it's not a problem to actually print the proper grey tone, but it's a problem as far as not understanding why there's white vertical banding marks no matter what Roland spot color (grey) I use... I've tried double passing, slowing the head down, different color management settings and although it's printing the proper grey tone, it also prints inconsistently using the Roland spot greys...

Also, in the images, I am also using a Roland spot black (the darker parts in image) and the darker parts are not affected by the whiteish vertical banding, which tells me it's not due to anything mechanical (printhead, encoder strip, etc..). I figured because only the black nozzles are firing to produce the image that because I have a spot grey and a spot black that maybe one is taking nozzle pressure from the other so I printed the image without the spot black but even with just a solid box of spot grey the whiteish vertical bands were still there...

Please help.....


This image is for overall orientation

This image is a close up showing the whiteish vertical banding

 

[Patentagosse]

Welcome to my world... 'Been struggling with that kinda shit for a while. Sometimes it's decent, sometimes not. Now that I have 2 lines off the print test (which I cannot clean) I'm getting white hair lines in my greys.

I have a VS-540 so we're in the same boat...

Have you tried to save as JPG, CMYK, Hi-Res? Sometimes it may solve or decrease the issue.

 

[Patentagosse]

Last week all my greys (file in PDF coming from ad agencies or customers directly, not the one I designed here using RVW colors) were printing pinkish. Not a li'l "normal" pinkish, PINKISH. Just figure a faucet on a plumber's van, done like a year ago, colors came out very nice, 'had to redo the whole driver side due to an accident, reopen the same file, use the same profile / media but the chrome is so pinkish it's like copper-plated (...). The tech spent the whole day here tweaking every possible setting to make it print like a new (in-deep cleaning of everything, changing all scrappers, felt, wipers, etc...). He said printer is well-maintained, clean, low "milage"... he suggested to try different profiles, in different color management settings. It has optimized a lot of small "off" settings as service mode gives access to finer tunings but I'm still getting a li'l magenta in my CMYK greys. Not as before he came but still a li'l, just to keep me in the "damn it" zone. Clean enough to get decent results, clients will not complain 'bout that but I'm not 100% satisfied of my job, that's what keeps me from sleeping well sometimes...

 

[Patentagosse]

Life goes on...

 

[antant77]

Last week all my greys (file in PDF coming from ad agencies or customers directly, not the one I designed here using RVW colors) were printing pinkish. Not a li'l "normal" pinkish, PINKISH. Just figure a faucet on a plumber's van, done like a year ago, colors came out very nice, 'had to redo the whole driver side due to an accident, reopen the same file, use the same profile / media but the chrome is so pinkish it's like copper-plated (...). The tech spent the whole day here tweaking every possible setting to make it print like a new (in-deep cleaning of everything, changing all scrappers, felt, wipers, etc...). He said printer is well-maintained, clean, low "milage"... he suggested to try different profiles, in different color management settings. It has optimized a lot of small "off" settings as service mode gives access to finer tunings but I'm still getting a li'l magenta in my CMYK greys. Not as before he came but still a li'l, just to keep me in the "damn it" zone. Clean enough to get decent results, clients will not complain 'bout that but I'm not 100% satisfied of my job, that's what keeps me from sleeping well sometimes...

Thanks for the response! I use illustrator and used RGB and CMYK... when I set color mode to RGB and use a "grey" from the RGB color palette, it prints great (with no white vertical banding) but the grey is more greenish.... when I use the grey RVW spot color the color grey is perfect but it somehow produces the whiteish vertical banding... I don't have a problem with any of the RVW grey spot colors regarding color tone, as they only print black but I truly don't understand the white vertical bands in the print... like I said, the black in my image is a RVW black (K=100%) and that color prints flawless deep black... I just don't understand how the use of the RVW greys are producing the white vertical banding...

I'm going to try what you suggested by save as jpeg... I saved as PDF and still same results so I'll give a try...

 

[Patentagosse]

If your grey in RGB are great but greenish, why don't you boost a li'l one of your channels? Usually greys in RGB are all same values (R: 117 G: 117 B:117) but if you boost one of 'em of few (or drop the Gs), you should get rid of the greeenish. Remember the laminte film affect the color and surrounding lighting... I always match my colors outside under 12 o'clock sun. Here, due to neon tubes (cool white), it has to be a li'l pinky inside to look perfect outside. If the greys are amazingly perfect in the print room, they with turn greenish in the parking lot.

 

[MasterPat]

The problem is NOT hardware. It is NOT Software. It is user problem. To get a decent gray, you must define the color as a percentage of black, not CMYK, just K. Then you must get it to your printer without the s/w switching it back to CMYK.

That said, whenever I have this problem, it takes a while to get it right; but don't worry about your encoder strip or other h/w. You might want to put a bunch of grays on the side of the image, then just print those only, and pick the best one, then change the art color. Try using PMS colors, and maybe the Hex one. But it has to ba onloy black/white from the cartridge, or you'll get the mud.

 

[nickgreyink]

Gray is the hardest color to print right. The best way for true gray is a percentage of black with no other colors, but there are different shades of gray lake Pantone's Cool Grays.

We actually printed out a Pantone chart with all the colors to see how the grays would come out.

http://andvel.bg/wp-content/uploads/2015/02/PANTONE-Process-Color.pdf

As for the banding it maybe a heat issue. Have you fiddled with the heat settings to see if the it prints better?