Print Curves

[irreality]

I know this topic has been discussed to death on these forums, But Im still confused about one thing.

Why are Target Curves not exactly equal to the Printed dot percentage ?

IE- So if im trying to Print a 50% dot why is my Target Value higher than that ? -

Is this a compensation thing for said standards. Ie G7, ISO ? To give a good grey balance ?

Im still confused as to this point - Hopefully someone can enlighten me.

Thanks.

[gordo]

Why are Target Curves not exactly equal to the Printed dot percentage ?

IE- So if im trying to Print a 50% dot why is my Target Value higher than that ? -

Is this a compensation thing for said standards. Ie G7, ISO ? To give a good grey balance ?

It's because Target curves are based on historic dot gains (TVIs) resulting from the use of linear film as the standard file interchange format.

best, gordo

[irreality]

So its based on TVI

What would be the best way to go about figuring out what my target curve should be set at ?

This obviously isnt an arbitrary curve ? Or is it .... hrmmm

[gordo]

So its based on TVI

What would be the best way to go about figuring out what my target curve should be set at ?

This obviously isnt an arbitrary curve ? Or is it .... hrmmm

The target curve is not set - it is chosen.

You can choose an industry standard appropriate for the type of printing that you do, (ISO 12647, SWOP, SNAP etc.) or if you want to print different, then you can do some press tests and develop your own target curve.

best, gordo

[irreality]

THANK YOU SO MUCH !!!

this has been boggling me for ages - Nobody Ive ever asked was able to give me such a precise answer. (even the international colour co-ordinator for our company)

So,

This obviously leads me to another couple of questions, More specific to just me.

1) What standard would be most appropriate (or one you would recommend) for UV printing on PVC. Its all i essentially print on.

2) Where would i find a list of these standards and their intended final values.

thanks again.

[gordo]

1) What standard would be most appropriate (or one you would recommend) for UV printing on PVC. Its all i essentially print on.

2) Where would i find a list of these standards and their intended final values.

thanks again.

1) I'm not familiar enough with the type of work you do to comment.

2) You might start rummaging around here:

FOGRA characterization data

and here:

ISO - International Organization for Standardization

good luck, gordo

[Lukas Engqvist]

@irreality If you are wanting to match your output with CMYK values on coated then you should perhapps look at using a curve for coated. Most customers who choose to work in CMYK and even advertising agencies that arrive at "specific CMYK" for a certain logo, assume that e.g. 30M 100Y will look the same irrespective of substrate and printing technique.

You will have to decide if that is the way your customers think. If so you will have to make a TVI curve so that they get the result "they expect" as much as possible.

As you understand there is some choice and some guessing, but once you have chosen depending on what you guess your customers think, be explicit in telling customers what route you chose and why, that way the uninformed will get "what he expects" or as close as you can get to it, and the informed customer knows why you have chosen to work that way.

[irreality]

Well thanks again everyone for your guidance it has been most helpful.

Ive decided to start with the Fogra 40 Standard. as it seems to be a well rounded standard.

I will definitely make some tweaks from there. Which will lead me into creating an ICC profile for our press - which i have already done once....( But Ive never seemed to get the results that I would like)

And im sure i will be back with questions about that.

[Bloodsaler]

For the UV printing and PVC part,I advise you find the standard through your own condition.Like FM screen,there`s no a certain standard that support this kind of printing,but the turth is FM screening will get more brighter and colorful samples.Such high level companies almost like using this kind of screen print their high level job.and the only can find the standard by their own`