I'm looking for the best way to this:
Any input is appreciated. Thank you.
Unfortunately the art that was sent to us was created by about 26 different individual squares, each with a progressively lower screening layered on top of the previous square. When we go to output the film, obviously there is not a smooth transaction between gradients. It pops out when we go to press. We were hoping to fix it up on our end.
I've been searching for a plugin to allow the creation of a square gradient but haven't had any luck so far.
What badchess said.
To elaborate, you may:
1) Delete all but the largest square and make sure it is just solid black,
2) Create a copy in front, reduce its size (maybe to 1% or so), and change the solid colour to white,
3) With Object>Blend>Options set to Smooth or the desired number of steps, select both squares and Object>Blend>Make.
Thank you for the replies. I did do this, saved as a PDF and checked the file Acrobat. Acrobat seems to only recognize full percentage screens? The transition of the gradient screen went from 9 down to 1, except it only showed whole numbers. It looked fine on screen. Then, I placed the file in InDesign so we could step it properly for the presses. After this, I exported the file as a PDF. Now, the screen transition in Acrobat read as 9,8,9,8,7,8,7,6...and so on. I assume this has to do with the blending, but the straight save as a PDF from Illustrator didn't have the differing sequences for screen gradients. Both looked fine on screen and appeared to have a visually smooth transition; however, when we output the film, the transition on the negative didn't look smooth whatsoever. A press test confirmed this. Now, I may just step the file in Illustrator and hope this makes a difference.
Are there any suggestions how to make the transition smoother? Should I apply more steps? I used 50.
Again, to sum up: On screen the gradient trasition looks smooth, but on the negative and on print, it looks bad. Also, why does Acrobat using the object inspector screen only show whole number screen percentages? We work with gradient screents constantly and never had I had a square gradient like this. I hope it's not something more technical with the RIP software and line screens.
Unfortunately I actually need to go from a green area screened 10% down to the same green, only screened 3%. From what I can tell, the smooth option doesn't work for smoothing the same colors even if they are screened differently. I am able to use the "steps" and then smooth which gives the gradient a good appearance on screen, but as soon as the negative is output, it looks like a staircase.
I'm not sure why you are still getting banding, but you could try this, make your .ai file go from 100% to 30% in the two boxes, then use opacity (10%) in InDesign to reduce it to the desired amount. I assume you are exporting your InDesign file to PDF, under compression, choose do not downsample. When viewing in InDesign use high quality display (View> overprint preview). If all else fails, open your .ai file in photoshop and add a little noise (filter> noise> add noise> gaussian), since this will reduce contrast a bit, you will need to start with a better ratio, like 100% and 10%.
Acrobat will only show you whole numbers in output preview, and the gradation should appear smooth.
Stocastic screening is also an option, but if you had it you probably would be using it.
If you are using a spot color green, you might see some improvement on your film with a different screen angle.
Why not just divide the largest outer square into four identical triangle (draw two lines from from diagonal to diagonal and pathfinder > divide)
So you now have 4 separate objects - all identical triangles.
Apply a gradient fill to each.
Rotate the gradient fill in each 90° per tri (left and right have opposite directional fill, as do top and bottom).
From what I can tell, the smooth option doesn't work for smoothing the same colors even if they are screened differently.
What gave you that idea? Works perfectly for me.
On the other hand a blend (or gradient) that covers a range of only 7% is almost bound to be a bit steppy but I doubt that in such a light tonal range it will be noticeable.
I tried it and can't make out the steps on screen.
Yeah, it appears perfect on screen, but when ripped to the neg, the banding is quite visible....as far as using a rasterized image from Photoshop, how would that help reduce the banding? I'm not opposed to that idea, in fact I will do that tomorrow. I'm just curious. See, I can get the gradient perfect on screen in Illustrator, the issue is when it's ripped on a neg. I figured I was doing something incorrectly; however, now I'm starting to doubt that. I just hope it's not a calibration issue with our rip hardware...that's a different beast. Anyway, like I said, I will attempt using a tif tomorrow after a press test.
You're obsiouvly no novice, the raster suggestion was just to help you get an easy square gradient into your Illustrator file, since it only natively offers linear and elliptical; a workaround is needed.
But yeah, it sure is starting to sound like the issue lies beyond Illustrator. Bummer!
Well is appears our rip software somehow was changed over from our default to a commercial setting resulting in improper line screens. All responses were helpul, but ultimately it came down to an improper setting on the software.
Thanks again. This forum has been a great tool.
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