So, you feel like you have a handle on sharpening digital images? You understand what all those sliders in Unsharp Mask really do?
Didn’t think so. Me neither.
I have more homework for you: read these 288 pages on this single step in the digital workflow. Bruce Fraser ("he’s not just a Photoshop guru, he’s a god") has a new book from Peachpit Press in the "Real World" series, "Image Sharpening with Adobe Photoshop CS2." It’s technical. It requires a comfort level with Photoshop that includes layers, channel masks, and blend modes. That is, it’s slightly over my head.
I’ve always been conservative in my sharpening routine (low radius, amount set at where I just start to see an effect), and I’ve always judged what I’ve done by what I thought was the right way: at 100% pixel view. I’ve been totally wrong on all counts all this time. Here’s one reason why.
Say your monitor resolution is around 100ppi (it ain’t always 72, another myth). Your output is 240ppi. You need to be looking at your image at around 50% to see the true effects of your adjustments. You need to judge your sharpening at that scale, not at 100%.
Additionally, it’s crucial to zoom out on your image at intervals of 50%, 25% or 12.5%. Odd zoom percentages (66%) brings out Photoshop anti-aliasing rendering which wipes out your ability to see the effect of sharpening on your image. So pick a zoom that’s close to the ratio.
So, why isn’t your monitor displaying at 72ppi? That number is the result of the size of your monitor display, divided by the resolution of your display. For example, my CRT monitor display is 14.25" wide. My resolution is set at 1024x768. I do the math and, hey! It’s 72ppi. My laptop now is 10.6" wide, also at 1024x768. Same number of pixels, smaller screen. It comes out to 96ppi.
I find myself in a similar situation, knowledge-wise, with Photoshop CS2 sharpening. Hence my use of the three-step Pixel Genius Photokit sharpening plugin. I believe Bruce is one of the partners in Pixel Genius.
Posted by: Lee Robinson | August 18, 2006 at 10:26 AM