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Author Topic: Photoshop help required: LAB  (Read 1091 times)

bjd

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Photoshop help required: LAB
« on: July 03, 2013, 12:16:09 PM »
Hi,
I'm trying to do something pretty simple, as usual I can't get it to work. While working on a picture
in LAB mode, I turned off the "A" channel, and it was a pretty nice effect. So I thought, I'd like to
save a version of this picture with those colours, unfortunately that doesn't seem to work.
You can switch them "A", "B" or "Luminance" off, make them invisible I guess, but they are always
saved.
So anyone any ideas how I can do this?

Cheers Brian 

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Photoshop help required: LAB
« on: July 03, 2013, 12:16:09 PM »

meli

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Re: Photoshop help required: LAB
« Reply #1 on: July 03, 2013, 01:33:55 PM »
from image menu > apply image > bg layer >channel A, set it to subtract (numbers in the side should be something like 2/128

Alternatively, just fill the A channel with 50% grey

bjd

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Re: Photoshop help required: LAB
« Reply #2 on: July 04, 2013, 08:22:14 AM »
from image menu > apply image > bg layer >channel A, set it to subtract (numbers in the side should be something like 2/128

Alternatively, just fill the A channel with 50% grey
Hi Meli, thanks very much.

I assume through this that I am removing all information from that channel?

Last night I couldn't get it to work as "subtract" was greyed out, I'll need to look into that.

Cheers Brian
« Last Edit: July 04, 2013, 10:02:07 AM by bjd »

meli

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Re: Photoshop help required: LAB
« Reply #3 on: July 05, 2013, 07:46:46 AM »
yep sometimes it greys it out, try this, before going into apply image, get into the channels panel and pick the A channel(or any single channel) so its the only one visible.

edit: And yes, both methods are doing essentially the same thing, remove all info of the selected channel, you might want to duplicate your layer first!
« Last Edit: July 05, 2013, 07:51:18 AM by meli »

bjd

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Re: Photoshop help required: LAB
« Reply #4 on: July 05, 2013, 08:49:42 AM »
yep sometimes it greys it out, try this, before going into apply image, get into the channels panel and pick the A channel(or any single channel) so its the only one visible.

edit: And yes, both methods are doing essentially the same thing, remove all info of the selected channel, you might want to duplicate your layer first!
Meli,
got it now. Works perfectly. Thanks.
Cheers Brian

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Re: Photoshop help required: LAB
« Reply #4 on: July 05, 2013, 08:49:42 AM »