Unsharp mask

[Ultra Magnus]

I've had a hard time working with unsharp mask. 99% of the time on full resolution photos all I end up doing is make my photos look noisy. When I resize pictures the usually come out fuzzy so I do an unsharp mask on the smaller photo's and imo they turn out great- nice and crisp. So, the question is, if I use a setting like 150%, 1 pix radius, 10 threshold on a 1024 x 768 resized image, on a 3XXX resolution (approx 3x the number of verticel and horizontal lines of resolution) should I set it to a 3 pix radius, and 30 threshold to get a similar result? How's it all work, anyway?

thanks.

BM

[another view]

The sharpening settings that work for one image probably won't be ideal for another. You can apply a small amount of sharpening as a standard procedure for shots that you post on the web, but trying to get the best possible image file for a large print will take more work.

I'd recommend one of two things. Get Scott Kelby's book "Adobe Photoshop (insert the version you're using here) for Digital Photographers". There is a whole chapter on sharpening - it can be very confusing and there are a lot of ways to do it. Also, there's Nik Sharpener Pro. I haven't used this software but it's supposed to be very good and easy to use; it's a plug-in for Photoshop.

[Ultra Magnus]

Sweet, thanks... I've been thinking more and more recently that I need a good photoshop book to get beyond only doing basic stuff.

BM

[Photo-John]

I use completely different sharpening strategies for Web than for print. The amount of sharpening used depends mostly on the final output resolution. But different types of images require different amounts and startegies for sharpening, too.

My basic Web recipe is to resize to 1500 pixels on the long dimension and use Unsharp Mask at Amount: 100, Radius: 0.3, Threshold 3-4

The I resize to 1000 pixels, and then 620, followed by another round of Unsharp mask at the same settings. That usually works really well for images I'm going to post on the Web.

For print my settings vary a lot more. Part of that is because you can never really tell what the print will look like from your monitor. Also, because I'm a lot more critical with prints. Generally my settings will be something like Amount: 200-300, Radius: 0.6-1.0, Threshold: 3-5

Sometimes I selectively sharpen specefic areas and even make transparent layers that I sharpen instead of the actual final image. Whatever works best. There are an infinite number of plausible strategies for sharpening.

One thing to watch out for is checking your sharpening on the monitor. It really doesn't work very well. I like to check my sharpening at "Print Size." Unfortunately, this is usually at a viewing ration of around 33% with my files. Photoshop doesn't display every zoom ratio well - and the 1/3 ratios are especially nasty. So I usually end up checking at 50%. I don't consider 100% to be that useful as it isn't what anyone is going to be looking at, unless it's a Web image. So for prints, try toggling between 25%, 50%, and print size. Don't expect Photoshop to accurately show you what the sharpening will look like on your print. Just use it to look for problems. I recommend finding a setting that looks good, and then backing off a bit. A lot of the time I think the prints look sharper than I expected. The biggest problem to look for is haloing on contrasty edges - like horizon lines. That's the first thing I check for. Too much sharpening will make an obvious halo anywhere there's a lot of contrast.

And buy a book :-)

A lot of people here like Scott Kelby's books. I'm partial to the Photoshop Artistry series by Barry Haynes. The foundation of my Photoshop knowledge comes from those books.

[Ultra Magnus]

Wow, that's a lot I never thought of before. It makes sense since prints print at a far higher pixels per inch than a monitor displays.

Thanks.
BM