How to adjust the hue?

[FrankZhang]

Here is my problem.
Recently, our shop is testing our presses. There is a press’s hue are different from the others. How could I get right hue by adjust some conditions?
How’s this “Hue” thing influenced press?

 

[Lukas Engqvist]

Hue is usually a grey balance problem. How are you testing the press? Are you testing it against ISO? If Cyan Magenta and Yellow are not in balance you will usually get a cast in the neutrals. It is possible to adjust the the transfer curves, but I would not attempt that without having a specific target, like ISO.

 

[FrankZhang]

Thanks Lukas
what is transfer curves? we have two curves,one for adjust printing plates,another for dot gain. Usually,for different color we have different dotgain curves. (CMY for 12%, K for15% at 50%).
Our plate making condition is 2400dpi 175lpi.
Do you mean that I should readjust my dotgain curves?

Frank

 

[Lukas Engqvist]

Yes that sounds ok, but it is not just the 50% dotgain that matters.
You need the whole shape of the dotgain gurve to be correct. You should look at the TVI for ISO. There are ofcourse other things that can affect such as the pigments of the primaries.
Note that the lower the TVI the dotgain maxes at a higher %. You will need at least 3 points to determine the overall shape of the curve 25% 50% 75% is a common reference.

 

[FrankZhang]

I checked TVI, the density for each color today, it all seems like OK. Now I suspect the printing sequence.we use KCMY for others, but KMCY for this one.

I will change the printing sequence and check it again.

Frank

 

[Lukas Engqvist]

That would affect colour, since it affects secondary colours. Will be fun to hear if this is getts you on track.

 

[FrankZhang]

Thanks for your help, Lukas. they have already settled.
haha, I am new for this industry, don't laugh at me.

 

[Lukas Engqvist]

Great Well this is the power of forum, you don't need to know everything, as long as you know where to ask (and are not afraid to do so)