Dot Gain
Dot Gain
- Subject: Dot Gain
- From: Paul Foerts <email@hidden>
- Date: Wed, 30 Apr 2003 12:18:25 +0200
Hi,
To answer your question...
"Dot Gain" has its origins in "conventional" prepress where halftone films
are used. Dot gain is by definition the difference between the printed tone
value and the tone value on film (film dot %) - which is your reference.
When you know the tone values on film and you can measure your printed tone
values with a suited densitometer, you can calculate the difference between
the reference (film) and the printed patches.
A film tone value of 40 can become 50 or 60 or more when printed, resulting
in a "dot gain" of 10 or 20 or more.
Other film values result in other dotgain values.
This tone value increase depends on the edge sharpness of the halftone film,
the plate properties (neg/pos, resolution), plate making standards, the
press, the ink and the paper...
Dot gain is "caused" by "mechanical" (about 1/3 - prepress/press) and
optical (about 2/3 - light absorbtion) .
In digital prepress, your reference "film value" changes to a virtual
reference (% in Xpress, Photoshop etc.) when CTP systems are used.
As there is no film involved the "Dot Gain" terminology is no longer valid.
Tone value increase is now part of the color management "black box".
Regards,
Paul
---------------------------------------------------------------
On 29-04-2003 17:45, "email@hidden"
<email@hidden> wrote:
>
Message: 10
>
Date: Tue, 29 Apr 2003 07:32:58 -0700
>
Subject: Dot Gain
>
From: MSD <email@hidden>
>
To: email@hidden
>
>
Good morning,
>
>
Some time ago was a discussion on dot gain.
>
Since then, I have been reading - testing - and paying attention to my
>
workflow.
>
The results seem to be -
>
A 30% dot gain does not "grow" a dot by 30%.
>
-
>
My 3% dot does not end up at 33%.
>
Anything over 70% does not end up solid.
>
>
Can anyone explain what everyone thinks they are talking about
>
when they discuss dot gain.
>
>
Thank you very much,
>
>
MSD
_______________________________________________
colorsync-users mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/colorsync-users
Do not post admin requests to the list. They will be ignored.