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Grayscale conversion

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asprague

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Jun 20, 2001, 12:50:53 AM6/20/01
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I saw a person demostrate converting a color image to grayscale by using
channels. The resulting image looked better than just using the mode.
Can someone point me in the right direction?


Thank You in Advance.


RossF

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Jun 20, 2001, 5:10:38 AM6/20/01
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On Wed, 20 Jun 2001 04:50:53 GMT, "asprague" <aspr...@kscable.com>
wrote:

>I saw a person demostrate converting a color image to grayscale by using
>channels. The resulting image looked better than just using the mode.
>Can someone point me in the right direction?
>

Basically, the color channels of an image give you several grayscale
images to choose from or blend together. You can convert between
modes, so RGB/CMYK/LAB give you ten possibilities. One easy thing to
do is to look at the individual color channels in the Channels
palette, and choose the one that looks best.

Better yet is Image>Adjust>Channel Mixer, check "Monochrome". Mix some
combination of the color channels that gives you a good result. If you
view the individual channels first, you can make an estimate of what
channels need to contribute. You can also try converting to/from
RGB/CMYK before using the Channel Mixer.

Check out Image>Apply Image. It has many options for blending channels
from several open documents.

Learn how to use Curves. With Curves, you can adjust contrast in each
channel, and within specific tonal ranges.

If you have objects or details that have color contrast, but little
brightness contrast, make selections on channels, and lighten or
darken to create additional contrast. Sometimes, you need to make a
really strange looking color image in order to get a good grayscale
one from it.

Ross

pent...@slow.com

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Jun 20, 2001, 7:53:16 AM6/20/01
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Image>Mode>LAB color

then
Window>Show Chanels

In the channel pop up click the LIGHTNESS channel

then Image>Adjust> colort/brightness,levels,etc, untill you get what
you want

you can then convert to greyscale if you want

Hope this helps


On Wed, 20 Jun 2001 04:50:53 GMT, "asprague" <aspr...@kscable.com>
wrote:

>I saw a person demostrate converting a color image to grayscale by using

Mr. Jim

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Jun 20, 2001, 10:00:47 AM6/20/01
to
asprague wrote:

>I saw a person demostrate converting a color image to grayscale by using
>channels. The resulting image looked better than just using the mode.
>Can someone point me in the right direction?

"Photoshop Channel Chops" covers this technique.

--

Jim Hall

My page:
http://hall.j.m.home.att.net

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