I happened to have an art paper with a texture that I really liked tucked inside my art drawer. This Strathmore Charcoal Hemp paper has a vertical lines that resemble some cold pressed watercolor paper. Unfortunately, I cannot simply place a sheet of the paper under a flatbed scanner since the grain won't show up in a scan. Instead, I had to find my old tripod, a cellphone tripod adapter, and a light source. (Aargh! upside-down image!)
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The makeshift setup was somewhat awkward, but it got the job done. After turning out all the lights in the room, I laid the green LED pen parallel to the bench and took a series of pictures until I got one with the lighting I desired. It took six photographs before I got a satisfactory result.
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After taking the desired picture, I imported the image into GIMP, cropped the section of the paper with the fewest imperfections, and converted the cropped image to grayscale. This is the final result:
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The result is mostly satisfactory, but there are still a few rough seams with larger canvases. Here is an example of the texture in use in Artrage 6:
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If anyone wants a closer look at what paper I used, here is an image of the brand of paper I used for this project:
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There must be a faster way of importing paper textures though. This whole process took two and a half hours.