# The final word on the CMYK halftone angle/s myth?



## tdigital (Sep 14, 2008)

Using a single angle is only bad if your press doesn't hold registration. In all other cases, using a single angle AKA "Flemenco Printing" is better than creating an artificial moire (multiple screen angles/rosette pattern) to avoid creating a moire in the first place.

I did my first 4CP job using a single angle and it came out great and most importantly... the client loved it. I'll do about 4 more 4CP jobs this week and see if the same continues to hold true regarding the single angle.

Here is an article that better explains what we're trying to accomplish with CMYK printing.

Screen Printing Four Color Process, How To Print Process, 4 Color Process Info

If someone has any information contrary to what i've found here, please share so we can all be better informed and more knowledgeable printers.


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## amp267 (Oct 11, 2006)

i would love to see your results, if possible post a pic


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## tdigital (Sep 14, 2008)

amp267 said:


> i would love to see your results, if possible post a pic


Absolutely. These were posted in another thread "My First 4CP Job" and you'll have to excuse the white balance/contrast as I took these pics with an iPhone


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## amp267 (Oct 11, 2006)

nice work........thanx for posting them


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## tdigital (Sep 14, 2008)

Thank you. Hopefully this can help to being the multiple screen angle issue to rest. I'm looking forward to getting a good reason multiple screen angles are still used these days.


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## printing40years (Dec 27, 2008)

your angles will need o change with whatever LPI you select then again with whatever mesh count you select. You are trying to avoid moire bit moire caused by mesh intereference. You don't want dots lining up with your mesh fibers. Every mesh count has a different number of threads per square inch, so the threads fall in a different place. As a rule try to avoid angles that end in 5 or 0. Any other number is better since most mesh counts end in a zero or multiple of five.


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## tdigital (Sep 14, 2008)

ImageIt said:


> The article reads like nonsense. To quote the article, "Dot gain is only a problem when you use a rosette.". This is simply untrue. Even 1 color jobs have problems with dot gain and there is no rosettes involved with 1 color jobs.
> 
> When all 4 colors match in frequency in angle, moire is not eliminated, but impacts the entire image with strobing. Take any 2 matching screens and move them over each other and you will see a strobe like effect.
> 
> fred


EXCELLENT! That part of the article seems to be super-biased towards using a single angle and is untrue. I think the context it was referencing is that its a "manageable" problem moreso than it not being an issue at all, but i'm not trying to even debate the merit of the article, it simply highlights a new paradigm in process printing.

I didn't see/notice any strobing on the 4CP shirt I printed, although I did only use 45LPI. Maybe its less of an issue with low line counts and maybe I'm just too inexperienced to notice it...

Fred - So, is any of the rest of the article correct or should I discard it all as rubbish? A lot of the article seems to make sense and the fact that the single-angle Flemenco style printing is what is highly suggested in Accurip makes it even more confusing.

I'm not sure what's right / wrong right now. Is it that Accurip/other printers "successfully" substitute a potential for strobing with creating a little moire (rosette)? Does that strobing you refer to even transfer to the shirt, or is it more-so something you'll notice on the positive only?


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## tdigital (Sep 14, 2008)

I said that Accurip strongly suggested the use of a single angle and here is the excerpt from their software manual.

*Excerted from the Accurip Software Manual*
_
Single Angle Printing (Flemenco Printing): is historically the best method for printing halftones.
Discovered in the late 1800s and patented by the Italian newspaper Flemenco users moved away from
single-angle printing ONLY because of registration problems of the cmyk printing presses during that time
period. Today the offset presses and screen print presses are far superior and have highly accurate
registration processes. Screen printers will find a remarkable improvement in their halftone printing by
moving to single-angle printing (you’re welcome!)

Not convinced? During discussions many will say “it can’t be done” and when asked why they simply
have no good answer other than someone they think was knowledgeable told them that. Ask to see their
prints and find out just how hard they had to work at them. The conversation always turns to the "secret
angles" they have discovered and usually its that they simply line up the black and yellow screen which
improves clarity and reduces dot gain. I always say "great idea" but why stop there? You have improved
your print by only 50%. If you can line up two out of four colors and the world did not stop spinning then
why can't you line up all four? Usually followed by silence and a lot of brow ruffling. Now it sinks in and
they smile._


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## jeffie (Jan 30, 2008)

Hey, man o man all this about "angles" "dot gain" "rosettes" & excetera makes my head throb...please define these terms...so as to assuage my ignorance ... ie: is "dot gain" an increase in dot diameter/shape on garment caused by what ever reason (viscosity of ink; screen tension; flood pressure;stroke pressure,angle;thread count,diameter...)I meen hells bells we want overlap on our spot jobs so we can account for misregerstration on the order of .003 inch, caused by myriad variables, on almost all our multicolor jobs. If cmyk is now "distilled" to the point that it is "point & clic" and press regerstration can happen a few min. you guys should publish a step by step CLEARLY written book/pamplet for us oh yea I for one would pay for it as we set up 3-4,multi color jobs /day most are less than 50 shirts..and if we could find a way to make cmyk work i'm in....jeff


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## PositiveDave (Dec 1, 2008)

Whatever works for you!
Single angle is good for t-shirts, low lpi and a rough surface, it doesn't work for graphics where they use higher lpi and therefore have lower tolerance of misregistration. In addition, t-shirts tend to be printed wet-on-wet whereas other substrates tend to be printed-dried-printed. Drying shrinks substrates, therfore you need rosettes.


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## printing40years (Dec 27, 2008)

Fred is correct. Rosettes produce the best possible photographic reproduction as long as you can avoid the moire. Moire happens when the dots line up over the strands of mesh and cannot print because the threads are in the way of ink flowing through. Proper angles helps prevent this phenomenon called moire. DPI is dots per square inch. Lower dpi generally makes it easier to print the design without moire. The angles can be set in Photoshop when you make your separations or you can spec in what you want if you send out your artwork for separation. Litho angles don't work for screenprinting because they use plates and have no mesh intereference, so if the people at the separation house are used to doing their seps for litho, you need to educate them and insist on the angles you want and the dpi you want, which is much lower than litho.


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## printing40years (Dec 27, 2008)

I recommend you select eliptical dots for best results.


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## PositiveDave (Dec 1, 2008)

and I would add - euclidean.


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## nivleik (May 20, 2009)

tdigital said:


> Absolutely. These were posted in another thread "My First 4CP Job" and you'll have to excuse the white balance/contrast as I took these pics with an iPhone


wait..if possible....can i see the original design/pics..??
i'm new to this t-shirt forum and in t-shirt printing too,but i want to expand my knowledge bout it...
the output is great...but is it the same as the original pic..???


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## skalyps (Feb 17, 2011)

I know these posts are very old and I hope someone can answer. I've been trying to understand the single angle concept. I've read a lot, and I dont know what is it, but I'm having a hard time understanding the single angle thing, from what I've read it sounds like the best optionf for 4CP but my question is, what is the setting that I need for my Accurip in order for me to print in "sinlg angle"? any help please, thanks.


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## TYGERON (Apr 26, 2009)

I don't use Accurip but one critical thing I will say is that there is no absolute, definitive, all-inclusive, "final word" on any aspect of screen printing and anyone suggesting or saying otherwise is absolutely wrong (LOL).

And be circumspect of anyone answering in terms of anything being the "best". 

"Single angle" is setting the angle of the C, M, Y and K haftone dots all at the _same_ angle as a remedy for undesireable moire patterns. I say _undersireable _because it's not something you get or don't. It occurs when patterns overlap and interfere. What's generally wanted is an acceptable or pleasing pattern.


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## ScreenFoo (Aug 9, 2011)

I think I know what the final word on CMYK halftone angles and myths is... it's facetiously.


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## TYGERON (Apr 26, 2009)

ScreenFoo said:


> I think I know what the final word on CMYK halftone angles and myths is... it's facetiously.


*Haa-haaaa. You're the best  *


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## jmjako (Jun 12, 2012)

To see is to believe. I will try both methods and decide whats best.


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## nizzbot (Feb 3, 2010)

skalyps said:


> I know these posts are very old and I hope someone can answer. I've been trying to understand the single angle concept. I've read a lot, and I dont know what is it, but I'm having a hard time understanding the single angle thing, from what I've read it sounds like the best optionf for 4CP but my question is, what is the setting that I need for my Accurip in order for me to print in "sinlg angle"? any help please, thanks.


Accurip prints everything at the same angle by default. It was designed to be used primarily for single-angle printing. 

To print at multiple angles you would have to have to go through great pains and change the settings in Accurip between each film.


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## PhilR (May 3, 2011)

nizzbot said:


> Accurip prints everything at the same angle by default. It was designed to be used primarily for single-angle printing.
> 
> To print at multiple angles you would have to have to go through great pains and change the settings in Accurip between each film.


I'm pretty sure you just disable the "lock screens" option. This gives the graphics application the option of setting the angles and LPI.


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## Syntek (Apr 25, 2013)

I'm sorry but after looking at the images posted of your single angle process shirts, (Keeping in mind I have not seen your original file, so I can't say for sure how it should look), I must say great job for your first attempt. (So don't take this too harshly.)

However, your colors are very washed out and muddy, I'm seeing a lot a halftones laying ontop of each other (Which is killing your color), and your edges are too soft.


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