Moving from 2400 to 3600 DPI

[aqazi81]

Hi All,

What are the pros and cons of moving from 2400 DPI CTP to 3600 DPI CTP?
Will there be any visible difference in print quality or is it just a marketing thing?

 

[gordo]

Hi All,

What are the pros and cons of moving from 2400 DPI CTP to 3600 DPI CTP?
Will there be any visible difference in print quality or is it just a marketing thing?

If you are imaging metal plates for general commercial offset - there will be no discernible difference between 2400 and 3600 dpi in the presswork.

 

[aqazi81]

Lets say we want to do magazine work, like high end fashion magazines.

 

[Slammer]

Lets say we want to do magazine work, like high end fashion magazines.

Same difference, readers will simply not see any difference for AM screening between 2400 and 3600, at least not enough to explain the slightly more demanding press and prepress requirements to your companies beancounters, now if you look at FM screening then it will become interesting.

 

[Repro79]

Better to look on hybrid screening like Agfa Sublima, Esko Highline that can be give more attractive visual quality and they use 2400 dpi.

 

[Slammer]

Better to look on hybrid screening like Agfa Sublima, Esko Highline that can be give more attractive visual quality and they use 2400 dpi.

Yup Hybrid is another nice screening to evaluate. But I did find it a bit difficult to work with in the transition areas.

 

[Repro79]

I know some printing houses that everyday use 240 and 280 lpi Agfa Sublima with good stable results

 

[gordo]

Whoa! Are we talking about dpi (as per the OP) or halftone screening?

For the record - other than the tone range from about 1%-2% and 99% -98% - there is NO difference between conventional AM screens and so-called hybrid AM/XM screens (Sublima, Esko Highline, etc.).

If you're looking at changing your halftone screening and wanting to do "magazine work, like high end fashion magazines" and want to take advantage of the benefits of FM without its downsides then you really need to evaluate Auraia DM screening (http://www.hamillroad.com/products/auraia/index.html). In addition to being used to print hundreds of millions of heatset magazine pages it is also used to print newspapers (using ECRM violet CtP). For just one example, my local daily newspaper has been printing with it for the past 3 years.

 

[aqazi81]

Whoa! Are we talking about dpi (as per the OP) or halftone screening?

For the record - other than the tone range from about 1%-2% and 99% -98% - there is NO difference between conventional AM screens and so-called hybrid AM/XM screens (Sublima, Esko Highline, etc.).

If you're looking at changing your halftone screening and wanting to do "magazine work, like high end fashion magazines" and want to take advantage of the benefits of FM without its downsides then you really need to evaluate Auraia DM screening (http://www.hamillroad.com/products/auraia/index.html). In addition to being used to print hundreds of millions of heatset magazine pages it is also used to print newspapers (using ECRM violet CtP). For just one example, my local daily newspaper has been printing with it for the past 3 years.

How do we differentiate which screening technology is better than others? What are the basic parameters?

 

[gordo]

How do we differentiate which screening technology is better than others? What are the basic parameters?

That's a very profound question.
IMHO
Printing is the process of reproducing an original image multiple times. As such it should be a faithful reproduction of the original and should not introduce any elements that are not part of the original.
Halftone screening in offset (and flexo) is a method to convert an analogue/continuous tone original into the binary format needed for a press.
So, the halftone screening method should, as much as possible, be a faithful reproduction of the original and should not introduce any elements that are not part of the original. IMHO FM type screening does this better than AM and is one reason I prefer FM over AM (there are other benefits to FM but that that's a different topic).
When it comes to AM and derivatives like hybrid AM/XM a similar rule applies and you have to look at the subtle details.
For example, in a classic AM screen (Euclidean round/square/inverted round) there is an optical bump at the 50% tone. So you would look at how the screen deals with that artifact to minimize its visibility. Or you could look at rosette drift from clear to dot centered over the diagonal distance of a plate ( rosette drift causes tone and color shifts). I could write a book on the topic LOL This blog post will give you some of the basics: http://the-print-guide.blogspot.ca/2009/02/am-screening-halftone-dot-shapes.html but, of course, one can go much deeper into the subtle details.

 

[aqazi81]

That's a very profound question.
IMHO
Printing is the process of reproducing an original image multiple times. As such it should be a faithful reproduction of the original and should not introduce any elements that are not part of the original.
Halftone screening in offset (and flexo) is a method to convert an analogue/continuous tone original into the binary format needed for a press.
So, the halftone screening method should, as much as possible, be a faithful reproduction of the original and should not introduce any elements that are not part of the original. IMHO FM type screening does this better than AM and is one reason I prefer FM over AM (there are other benefits to FM but that that's a different topic).
When it comes to AM and derivatives like hybrid AM/XM a similar rule applies and you have to look at the subtle details.
For example, in a classic AM screen (Euclidean round/square/inverted round) there is an optical bump at the 50% tone. So you would look at how the screen deals with that artifact to minimize its visibility. Or you could look at rosette drift from clear to dot centered over the diagonal distance of a plate ( rosette drift causes tone and color shifts). I could write a book on the topic LOL This blog post will give you some of the basics: http://the-print-guide.blogspot.ca/2009/02/am-screening-halftone-dot-shapes.html but, of course, one can go much deeper into the subtle details.

Thank you Gordo for your always knowledgeable answers.

 

[Slammer]

I could write a book on the topic LOL

Why don´t you?

 

[gordo]

Why don´t you?

Because there's no payback from the print community for the work it would entail.

 

[Manprint]

Money a lot of people hated, glory on the othe hand none