Unsharp Mask – Woot!

After what seems like forever, I was finally able to order my first print proof of Critter Tales. Besides checking things like page numbering, formatting consistencies, overlooked typos, or even blatant mistakes, this is my first look at the photos, both cover and interior. Like 5 Acres and A Dream The Book, the cover was too dark, but the interior photos were better than I hoped. Still, they all needed some work.

What needed to be done to most of them was to increase contrast. I do this with the “Brightness-Contrast” tool in Gimp. Both are increased to give a sharper contrast, which translates as better grayscale images in print. For the record, I’m increasing brightness by 30 and contrast by 20. Only a second print proof will tell me if this was right. I should mention that I save the adjusted image with a different name by simply adding a “b” to to it. I’ve learned the hard way to always preserve the original images, plus each of the changes.

Photos that were taken with a camera set for a sharper photo were the easiest to do, but some of them were taken as 640 by 480 pixel images for email or the internet. I’ve learned how to enlarge these by first increasing PPI (pixels per inch) to 300 and then resizing to, say, 4.5 by 3 inches. Most of the times that works, although some still end up looking rather pixelated.

I was researching this the other day, and learned about “Unsharp Mask.” ¬†In Gimp it’s found under ¬†Filters > Enhance > Unsharp Mask. It’s a tool folks use to sharpen photos that are soft-looking. For print, the recommended settings are 1.5 for radius, and 1.0 for amount. I’m leaving threshold at 0, because I don’t know what it does. I don’t actually know what any of them do, although I found an excellent article explaining it – “Understanding Unsharp Mask.” Once I’m not pressed for time, I’ll give it a read so I know what it is that I’m doing!

Here’s an example from “Kitty Tales” to show you the difference that the tweaks have made.

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After I finish tweaking all the images, I’ll order another proof. Hopefully no further adjustments will need to be made, but I’m not holding my breath.

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