C'mon you love it - gradient banding!

[shred_thumb]

Hi all -

I've sat on the sidelines and simply read all of your advice in the past. Now I find myself in need of it. I know this has been approached from every angle in the past and I've scoured the archives looking for an answer.....to no avail.

Here's my dilema -

Gradient from Roland swatch "Black 12" to white, approx. 2' high, running the length of a full size SUV, (printing in 2'x4' panels approx.)

Gray is neutral - no problem there. The gradient is not banding. The print head is leaving visible banding, no matter what configurations I use, (see attached photo).

Roland XP-540 | OEM inks | 3M IJ180C | VersaWorks 4 | PGCT: Premium Cast Vinyl profile - error diffusion, colorimetric matching method, convert spot color

If anyone has any insight / advice to share, I'd certainly appreciate it. I've ran my entire gamut of options and have not found "the happy place"!

 

[ucmj22]

is the banding in the direction of the print head, or going front to back on the printer? you cant really see the banding too well in the pic.

 

[shred_thumb]

It's running with the direction of the print head, (vertically in the photo). It's slight, but my customer is super critical. I need it to be non-existant.

 

[CarNate69]

Change it from 8 pass to 16 pass, then roll with it. Slower printing, but should get rid of it.

 

[anothersign]

I would download the profile for that material but i think the head speed will default to 1000...drop that head speed to 720 i think this will help

 

[shred_thumb]

Thanks guys....keep em coming. I've tried the specific profile, and dropped head speed to as low as 125 / unidirectional with no improvement.

 

[Bigdawg]

http://forums.adobe.com/message/3035634

There is a reply on the page with some detailed info... basically the formula for where and how (mathematically) you will see banding.

 

[AUTO-FX]

How you are producing the gradient could be part of it. I know if I creat a gradient in flexi, it is sometimes not the most desirable outcome. Can you print a fill with gradient and get satisfactory results? that might help rule out the software / machine?

 

[shred_thumb]

The gradient was created in AI CS5. I've ruled out the art as the problem and am convinced it's the printer. I know it's tough to see in the original photo, but if you look at the right half, you can see the banding created from the print head.

 

[Bly]

Is the grey printing with 4 colours or is it just using black?
If it's black only you will have banding.

 

[Mike Paul]

Try rasterizing the file and add a bit of noise. For the record, you can't print gradients with Roland's spot color library, for some odd reason it's not supported.

 

[HulkSmash]

try turning down the heat a bit?

 

[CarNate69]

Clean the heads, ensure the test print looks right. If not, take control of the hardware issues first, then worry about software tweaks.

If it's a vector file, For a true black, set in 75% Cyan, 68% magenta, 65.5% yellow and 90% black for the file to print a really nice black, or (0, 0, 0) for RGB.

 

[shred_thumb]

Printing black ink only. The blend specs "RVW-BK12A" to white. Not sure what you mean by the spot color library not being supported, Mike.

Bly - so as far as you know, what I'm trying to accomplish is impossible?

 

[ucmj22]

I found that if you print roland spot colors with out converting the spot color and with the density control only color profile, It hits the spot colors. I would also try bumping your print heater to 50c. This probably wont solve the problem though since you already slowed the print head speed down to 125 it probably isnt a ink dry time issue. I would try and rasterize.

 

[shred_thumb]

I've done the rasterizing - noise / blur / 8-bit vs. 16-bit tifs. Ugh.....thank you for all of your thoughts on the subject though.

 

[Malkin]

When I have had similar issues, I had thought it was nozzles dropping out on the black head. Since only the black is printing, there are not other colors to add some noise to help hide the banding.

 

[Bly]

Printing black ink only. The blend specs "RVW-BK12A" to white. Not sure what you mean by the spot color library not being supported, Mike.

Bly - so as far as you know, what I'm trying to accomplish is impossible?

Yup. Try it with a 4 colour grey and see the difference.
Of course you will then find out how accurate your profile is.

 

[FKAT]

Ensure adjusting the (Feed) Calibration on the printer for the product you are printing. The PGCT profile has an imbedded feed calibration compensation for PCGT, not 3M IJ180C. The products differ in caliper by almost 1mil. This would contribute to banding.

The feed calibration can be found under the 'Printer Control' pane in VersaWorks. After making the adjustment on the printer, make sure that this window is set to 'Use Printer Settings'.

In terms of printing, PGCT was a coated product. The 3M IJ180C is not coated. You would be better off using the PWV profile.

 

[MikePro]

my computer's not showing your images in the post for some reason, but try eliminating the gradient by pulling it into photoshop to flatten to a jpeg and then reinsert it into illustrator.
...and then run your print in unidirection, high-pass, slow speed.

always works for me!