One of the basic things when using layers is duplicate and use of blend modes. Lets say that you have washed out Poser render and you want to get some quick contrast. First click and drag the Background layer (Its allways the first layer) on the second icon from the right on the bottom of the Layers palette (Create new layer icon, looks like a paper). By doing that you have duplicated the layer, another way of duplicating layer is to simply press CTRL+J. Click on the drop down menu where it says Normall and choose Multiply. If the effect is to heavy, click on opacity and lover the amount. Now you can flatten the layers by clicking on little triangle in top right corner and choose flatten on the bottom of the list :)
Tihomir
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