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Old 12-14-2003, 02:34 PM
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bmckenzie bmckenzie is offline
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Join Date: Jan 2003
Posts: 11
Default Deeping shadow enhanced by Surfer31

Thanks for the workshop. Can you talk me through what you did in more detail? I'm something of a Photoshop amateur...

>Made an alpha mask on the areas lit by the sun and corrected the colors and contrast using Levels and the Curves to fine tune in PS.

What is an alpha mask? I do I create one using PS 7? Do you use a feathered selection (I've learnt that!)?

>Then I selected only the sky and worked out the colors. I didn't "touch" the shadow areas because I like the contrast between the volcano and the rocks in the foreground.

Worked out the colours? You mean desaturated or what?

Thanks for your advice, Bruce
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Old 12-14-2003, 08:19 PM
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Surfer31 Surfer31 is offline
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Posts: 30
Default Re: Deeping shadow enhanced by Surfer31


Thanks for your notice about my workshop. I must appologise to you because sometimes I forget to be more specific in the workshops I do in TE.

First, an "alpha mask" is a mask I usually create on an alpha channel (Channels palette in Photoshop - lower right of your screen in PS). This way I can select only parts of an image that I want to work on. In your picture it was easy to select only the bright areas of the image. I directly used the Paintbrush tool in the alpha channel and literaly painted the bright areas using various settings of the paintbrush tool (different sizes and hardness values). After creating this selective area, I imported the selection into the RGB image, resulting in a selection of that "white image" in the alpha channel. Then I opened the Levels dialog box (Control+L) and worked between the various RGB channels until I got the desired color correction on the image. To fine tune the color correction I opened the Curves dialog box (Control+M) and like in Levels, I applyied diferent values for the different RGB layers. You can try for yourself, moving the sliders and see what happens in the image. It's a bit trial and error at first but if you experiment a lot you end up mastering the technique.

The sky still had too much yellow and green so I used the Magic Wand tool to select only the sky area. This was easy because there weren't any clouds or other elements like tree branches to "avoid". Then I used again Levels and than Curves to correct only the color of the sky.

Sometimes I use various alpha channels and mix them in various ways to get exactly the selection I want. It's not as complex as it seems. Only experimenting a lot and/or buying a good book about the matter will teach you a lot about this, and other very usefull functions in Photoshop.

I hope I was helpfull. Please feel free to email me or post in this forum if you have other questions.

Keep up the good work.

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