Re: Dot Gain
Re: Dot Gain
- Subject: Re: Dot Gain
- From: Jim Rich <email@hidden>
- Date: Tue, 29 Apr 2003 15:18:34 -0400
On 4/29/03 2:46 PM, "Bruce J. Lindbloom" <email@hidden> wrote:
>
Roger Breton wrote:
>
> In the end, I think we all suffer from a "dot gain phobia", meaning we don't
>
> want any dot gain or when there is, we would like t to be different or
>
> smaller or larger, because we're so accustomed to se it one way or another.
>
>
We should understand that dot gain is good, not bad. If the dot gain of a
>
printing system was zero, then the CMYK values would represent reflectance,
>
which is the CMYK equivalent of a gamma = 1.0 RGB system. At 8-bits per
>
channel, this is not suitable for avoiding visual quantization
>
(posterization) defects.
>
>
We know that an RGB working space having gamma = 2.2 is more visually
>
uniform than one with gamma = 1.0. Similarly, some amount of dot gain (20 to
>
30%) redistributes the CMYK tone scales in a more visually uniform way.
>
>
This is good fortune because the gamma 2.2 that is part of the physics of a
>
video display system, and the 20+% dot gain that falls out of an offset
>
printing system, both help distribute tones more evenly visually and both
>
came about by "accident" (i.e. they were not specifically designed in for
>
that purpose).
I just wanted to add to this post, that another issue about dot gain is to
determine how much your imaging system has and then learn to control it.
If you don9t know how much dot gain to expect then your process (usually
from the start) is out of control and then you are wasting time and
materials and money.
Jim Rich
_______________________________________________
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.
| References: | |
| | >Re: Dot Gain (From: "Bruce J. Lindbloom" <email@hidden>) |