Step 1:
Open a photo and apply your first effect (here Cartoon 1).
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Step 2:
Then copy the resulting image to the clipboard (either by right-clicking on the drawing and choosing 'Copy drawing to clipboard', or by pressing CTRL+C or by clicking on the third icon in the toolbar).
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Step 3:
Now apply your second filter (here Painting 6 - oil painting, with increased brushstrokes intensity).
Once the painting is finished, paste the previous cartoon image from the clipboard (either by pressing CTRL+V or right-clicking on the first image and choosing 'paste image from clipboard' or click on the fourth icon in the toolbar, as shown here).
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Step 4:
The Cartoon image you had created in step 1 is pasted in both panes. Your oil painting has disappeared, but no panic, this is normal.
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Step 5:
Just click on the undo icon (as shown) or press CTRL+Z.
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Step 6:
Now the cartoon image in on the left and the oil painting is on the right. The final step is to choose the 'Merge source and result images' effect and voila!
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The result:
With a frame and texture added.
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Best regards,
David