Trapping help - Can the following be trapped?

[AlexRossi76]

111111111111111111

 

[chevalier]

Short answer: yes
Longer answer: yes, but you may not like the options

There are few ways to work this out. I'll create an Ai openable PDF for you showing options and post it in a bit.

 

[AlexRossi76]

111111111111111111

 

[chevalier]

I couldn't get this to upload as an attachment to the forum. So here is a download link. Note to future readers: The file link is good until Jan. 24, 2014. If you are reading this post subsequent to this date and want the file reply to this message thread and I will post a new link.

The trick in these scenarios is typically to limit the ''intensity" of the trap (i.e. screen the trap). Do realize software applications and proofers are not going to simulate opacity of the inks extremely well if at all. Inkjet proofers are notoriously bad about extremely exaggerating trap contrasts. You really just have to be intuitive about considering ink process opacities...

If you are going to limit trapping intensity follow these guidelines:

1. Maximize the intensity of the trap (start high and then back off to what is suitable)
2. Typically never go below 50%. Below this point the screening becomes a serious problem of showing white gaps. It depends on the colors you are trapping too. The darker the colors the more potential for white (substrate) to end up showing.

 

[DCurry]

For type that small, I would think about just overprinting it. It may take on a greenish tint, but by the time you trap it it's going to almost create an overprint anyway. The other option is to make the small type 100% Spot Blue and a screen of the yellow. As mentioned above, this reduces the intensity of the color change while eliminating the need for a trap.

 

[AlexRossi76]

111111111111111111

 

[AlexRossi76]

For type that small, I would think about just overprinting it. It may take on a greenish tint, but by the time you trap it it's going to almost create an overprint anyway. The other option is to make the small type 100% Spot Blue and a screen of the yellow. As mentioned above, this reduces the intensity of the color change while eliminating the need for a trap.

I was thinking overprinting the text could be an option, but dont really like the colour it produces. What do you mean a screen of yellow? I asked the same question above. Is screen a percentage of a spot colour?

 

[chevalier]

In practice I very rarely overprint these scenarios. Trapping software (I use Esko PowerTrapper) is so powerful that I don't have to make manual overprints for these scenarios as the software's trap will literally create an overprint.

What DCurry is suggesting is essentially the same thing I did.

Re: 50% limit
See the attached. When you cross the 50% mark in screening there is more void than dots therefore trapping begins to lose its purpose (not showing substrate to the eye). The attached isn't perfect or to scale but you get the idea.

 

[AlexRossi76]

111111111111111111

 

[Alois Senefelder]

A Visit is required !

A Visit is required !

Hello vertyuk.


I suggest you visit Gordon "Gordo" Pritchard's Blog - The Print Guide


lots of useful info for you !!!!!


Regards, Alois

 

[AlexRossi76]

111111111111111111

 

[chevalier]

a gross oversimplified explanation of screening:
dots are created (they can be round, square, elliptical, etc.) and the diameter of the dots increase or decreases based on the desired ink coverage

at 25% ink coverage - 25% of the area is covered with dots of ink and the remaining 75% is void
at 25% the dots will have considerable of space between them

at 50% ink coverage - 50% of the area is covered with dots of ink and the remaining 50% is void
at 50% the dots will have the minimum amount of space between
at 51% the dots begin touching each other

at 75% ink coverage - 75% of the area is covered with dots of ink and the remaining 25% is void
at 75% the dots are touching each other a lot

some inks and printing processes behave well when screened and some do not. Pantone 282 (the color mentioned) and other dark blue colors are notoriously bad at being screened for offset lithography. this has to do with the formula of the ink, particle size, viscosity and the process the ink is being printed with. Pantone inks were not formulated to be screened. These mixes were created with the idea of printing them as 'solids'.

gordo's blog - http://the-print-guide.blogspot.com/
bookmark it. possibly the best resource on the internet on the subject. the guy should be running his own academy on the subject.

everything he's filed under AM Screening ('traditional' halftone screening)
The Print Guide: AM Screening

everything he's filed under FM Screening (sometimes also referred to as stochastic. I did not bother trying to explain this or 'alternative' screening models, only 'traditional' halftone screening)
The Print Guide: FM Screening

 

[AlexRossi76]

111111111111111111

 

[chevalier]

I am always willing to help or inform someone who wants to know more. Sometimes I am accused of being over eager, too intense or too detailed. Put passion into what you do or you it isn't worth doing. This mantra annoys my wife to no end. I have z e r o passion for DIY home repair, etc. so well it isn't worth me doing…

lots of opinion in this answer:
"Expanded gamut" is a loaded term…
It may mean the printer is using a proprietary 6, 7, 8+ color set to achieve traditional CMYK gamut as well as Pantone colors and gamut beyond CMYK.
or
It may mean the printer is using "high fidelity" CMYK inks that are ran at higher density and are able to achieve a gamut greater than typical CMYK.

Expanded gamut isn't a bad thing in either case but it I hate the term. If you are printing HiFi CMYK say so, 6 color process say so, etc...

more opinion but specific to your design:
Colored fine type like this is a nightmare to build out of screens no matter how fine the dpi/lpi or micron size the printer is using. "Pullbacks" (the opposite of a trap) do not resolve this problem either.

edit:
gordo's blog has a whole section dedicated to "expanded gamut"

 

[AlexRossi76]

111111111111111111

 

[chevalier]

Put notes/warnings into the margin of your native files or PDF comments if you are only supplying PDF(s). Leave your contact info(s) and the printer will reach out to you if they need guidance.

I'm guessing your being fire-walled from talking directly with the printer (this is typical but really stupid). The politics of buyers is ridiculous.

 

[AlexRossi76]

111111111111111111

 

[chevalier]

something along the lines of:
"attention preflight/prepress: ensure legibility of thin yellow type on panel C when converted to process colors; convert to solid color [colorname] if necessary"

 

[michaelejahn]

Thanks for the trapping PDF. I have another question with screening. I understand now that screening is simply a percentage of a spot colour, ie/ 50% of pantone 282, or whatever given spot colour. My question is, how come with screenings / tints of spot colours they sometimes come out with noticeable dots like your provided examples?

Becuase that is what 50% "means" when you print a tint of any ink, weather it is 50% cyan or 50% Pantone 185 - there will be a line screen.

http://neolithgraphics.com/images/halftone_dots.gif

if you do NOT want a line screen, than you need to print a different Pantone color that is 50% lighter in tone.

Hope that clears that up for you - maybe you might appreciate reading up on this here:

Halftone Screens and Dots. Learn by free tutorials

 

[pcmodem]

I am curious as to why you are needing to trap this file in the first place. Any good printer should be doing the trapping for you.