I found manipulating the light source difficult without a mount for the light. My only option was to hold the pen light with my bare hand at a shallow angle to the paper. After one hour and six images, I selected the best image that had the fewest wrinkles in the paper grain:
I imported this image into GIMP as a png file, cropped the portion of the image with the fewest irregularities and saved the image as a grayscale. Here is the final result:
Here is an example of the grain in use in Krita. Notice the irregular seams between tiles.
Very cool! Did you edit the texture to make it seamless? I think you need to do it to get rid of the seams.
What I would do to make it seamless is to open the image in Krita, activate wrap mode, and maybe smudge the borders to make the seams disappear. Try it!
You can also use clone brush and smart patch tool to edit the texture
I tried your suggestion this afternoon to use the wrap tool and the clone brush and it mostly worked. Although the default intensity of the paper grain was reduced, this problem is easy to fix by increasing the contrast of the paper grain. Here is the edited paper grain. I used a larger section of the original photograph for this example:
As for the process of taking a photograph of the paper grain, I would like to know what other artists have done for this process.
I mostly scan my textures using a flatbed scanner and use wrap around mode to make it seamless.
How do you control the paper shadows on the flatbed scanner? When I scanned my paper through my flatbed scanner, the shadows on the paper were too shallow for any texture to show up on the paper grain.