Sharpening Methods

[lordjim]

Hi Everyone -

I knew about the USM method to sharpen an image but I learned about the High Pass filter method in a Photoshop class yesterday. So I made some research on the internet this morning and I found the following article which also explains the High Pass method:

http://www.peimag.com/pdf/pei01/pei0601/eismannpei0601.pdf

Other explanations of the high pass sharpening method can be found at:

http://www.luminous-landscape.com/tutorials/high-pass-sharpening.shtml
http://www.findarticles.com/p/articles/mi_zdpcm/is_200303/ai_ziff37312

You may want to use soft or vivid light in lieu of hard light as described above.

I thought it would be great to share the links as it may give some new ideas about how to approach sharpening.

Let me know what you think.

[tupe]

I just learned about high pass sharpening today. Very nice technique.

Soft light seems to work better than hard light for me so far, but I just read about using vivid light and overlay.
Trying these two, vivid seems more pronounced (like hard light), overlay more subtle (like soft light).
Lots of choices!

Thanks for sharing this. Here's a link to another tutorial: http://www.ephotozine.com/techniques/viewtechnique.cfm?recid=355

[BigRed450]

You will find that High Pass sharpening is more for problem images i.e. poor focus, small MP digicams, for edge enhancement. It has been around for some time. If you are shooting with a DSLR you will seldom see a need for High Pass. Try this very simple process.. Just delete the saturation and contrast steps if you just want to sharpen. This process works well up to 13x19" enlargements....

> open image
Add Contrast
> image > adjustments > Brightness/Contrast > add +5 contrast
Add Saturation
> image > adjustments > Hue/Saturation > add +20 Saturation
Convert to LAB mode for sharpening
> image > mode > LAB
> click on Channels palet
> choose LIGHTNESS channel
Sharpen Lightness Channel ( sharpening only the lightness channel won't sharpen color noise )
>Unsharp Mask A- 85 R- 1.0 T- 4.0
>UnSharp Mask A- 85 R- 1.0 T- 4.0 ( Yes the same setting twice )
Convert back to RGB
> image > mode > RGB Color
Save
> Save or Save As , your choice..

[CyberPet]

I read in Scott Kelby's book that you don't need to convert to Lab if you right after you've run USM go to the Edit menu and do "Fade Unsharp Mask" and in the popup-menu for Mode, choose Luminosity. It should be the same thing as to sharpen in the Lightness channel in Lab.

[tupe]

Thanks for the tips, BigRed and Petra. It's nice to have another couple of sharpening tools available.

The first link in Lord Jim's post:
http://www.peimag.com/pdf/pei01/pei0601/eismannpei0601.pdf
has a guide to "smart sharpening" that works well also. It's similar to Scott's
noise reduction approach, though not nearly as thorough.

I've tried several settings with the high pass technique, and now have way too many possibilities. Using luminosity, color burn, linear burn, etc., etc., produced several neat and potentially useful effects.

[BigRed450]

Petra: This is where things start to get repetative and contradictive. In Scott's latest book for CS2 he mentions the Luminosity fade, but still prefers the LAB lightness channel sharpen. Personally I prefer the effect of the LAB sharpen better, but many of these processes become personal preference. Elements users will have to use the Luminosity Fade process....

[lordjim]

BigRed, Petra, thank you. Sounds like a great method indeed. I will try it right after work today. Thanks for sharing.

[jfrancho]

This thread will be useful: http://photography-on-the.net/forum/showthread.php?t=83348. I've been spending some time learning to use this toolset, and the difference is significant.

[gmitchel]

This thread will be useful: http://photography-on-the.net/forum/showthread.php?t=83348. I've been spending some time learning to use this toolset, and the difference is significant.

The toolkit uses Highpass Filter sharpening for the final stage. One important step that is nearly always overlooked in the descriptions of Highpass Sharpening is to apply a Levels adjustment to the Overlay/Soft Light/Hard Light layer you use for sharpening the image. As you adjust the black and white point toward the center, the sharpening effect becomes more pronounced.

Also, it is important to protect highlights and shadows with any sharpening technique. Sharpening works by enhancing contrast. You should use the Blend If sliders on the Layer Style palette to protect the extreme highlights/shadows.

The toolkit handles these refinements for you automatically.

Cheers,

Mitch

[CyberDyneSystems]

That's some nice stuff BigRed.. I'd find +20 for saturation a little heavy most of the time.. I tend to see more like 10... but still it's obviously something that you need to "feel" for each photo.

[Carzee]

[ bookmark ]

[PhotosGuy]

Found this in another thread:
Out of Gamut: Thoughts on a Sharpening Workflow (http://www.creativepro.com/story/feature/20357.html)

[gmitchel]

Found this in another thread:
Out of Gamut: Thoughts on a Sharpening Workflow (http://www.creativepro.com/story/feature/20357.html)

Yes, Bruce Fraser's articles had a profound impact on me. My scripts follow a three-pass sharpening strategy, just as Bruce suggests.

Cheers,

Mitch

[BigRed450]

More good info Thanks.. Great job Mitch BTW

I have just got to the point that, all though these multi layered multi step sharpening processes may be better, unless you are producing images over 13x19", there is simply no need to go through all the trouble. At one point when we were using 3MP digicams it was imparative to process properly to get decent 8x10s or larger and so we had to go to great lengths to process our images, now, that is just not the case. I am not disagreeing as to whether these processes work, they certainly do, but what I am saying is, you have to decide if you really need it.

[gmitchel]

More good info Thanks.. Great job Mitch BTW

I have just got to the point that, all though these multi layered multi step sharpening processes may be better, unless you are producing images over 13x19", there is simply no need to go through all the trouble. At one point when we were using 3MP digicams it was imparative to process properly to get decent 8x10s or larger and so we had to go to great lengths to process our images, now, that is just not the case. I am not disagreeing as to whether these processes work, they certainly do, but what I am saying is, you have to decide if you really need it.

Yes, I agree, you do have to decide for yourself.

My scripts are perfectly compatible with one-pass or two-pass workflow, too. You can, for example, just use the output sharpener.

Most people with DSLRs these days are not shooting 3MP. Most are shooting between 5MP and 8MP.

My toolkit was not designed for the snapshot photographer with a digicam. It was designed for the serious amateur or pro who wants to craft the best image possible, whether that be a 6x4 at 180 dpi from a Nikon Coolpix or a 12x18 at 360 dpi from a Canon 1Ds MkII or even a 72 dpi Web image.

Some people shoot JPEGs and let the camera sharpening. It's not my preference, but that's why the cameras offer the feature. Different features for different users.

I never feel sensitive when people say my toolkit is more than they need. ;) Everyone has to ake their own decision about how much effort they want to put into their photography.

Cheers,

Mitch