Interesting method of sharpening w/out noise

[NorthernFocus]

The recent edition of Topaz News had a link to a video showing a different twist on using a high pass filter for sharpening. The method avoids enhancing noise in the base image. I've seen similar methods in the past but they were much more complicated and time consuming. For this one your software must be able to:

• work in layers
• create a high pass filter layer
• run NR on the high pass layer
• sharpen the high pass layer
• blend the high pass over the base layer in luminosity mode and adjust opacity

Here is a link to a video demonstration of the technique. It looks pretty interesting. As is typical I'm sure it will work well on some images and not on others. Looks like it would be great for architecture or anything with bold lines.

[James G]

Dan, interesting process, its similar to a couple of actions I developed for myself using Gaussian Blur/Surface Blur and Noise reduction to perform a kind of 'wavelet' sharpening.

I've just run the process on an image I processed this morning from the eclipse.

It certainly works and brings out additional info. I'm interested since it seems to be effective where there is limited differentiation between light and dark edges.


#1 Processed using the new sharpening technique


#2 Processed using my 'usual' sharpening technique


Will play with it a bit more but it definitely looks useful. (I do not have Topaz, but the filters available in CS6 seemed to be sufficient to generate the effect.)

Thanks for the link.. James

[John 2]

Probably received the same e-mail from Topaz as you Dan and I have been experimenting with the method. It can work quite well and I thought it worth posting one or two things that I have discovered so far.

It seems to be easier to control on larger images than smaller images. Small JPGs seem to be more prone to excess contrast. Only used TIFF images so far. Don't know whether it works with RAW files but I guess there is no reason why not.

You don't always need to post sharpen the High Pass layer. De blurring it in Topaz is sometimes enough.

You don't always need to use linear light to merge the layers. It is worth experimenting with that whole block of options particularly if the end result seems a little harsh.

You can of course apply this selectively by just erasing or masking out the High pass layer where you don't want to apply sharpening.

It seems to work quite well and I guess as a technique, it isn't reliant on Topaz software. Any noise software should do it. I think it might be a useful addition to the tool box.

[Shadowman]

Part of the video was unclear, after applying the hpf, did he say desaturate the layer?

[NorthernFocus]

Part of the video was unclear, after applying the hpf, did he say desaturate the layer?

Yes. He says is really fast about 1:25 into the video.

[Shadowman]

Yes. He says is really fast about 1:25 into the video.

Thanks Dan.

[jcuknz]

Sounds like a variation on the view expounded by Larry Bolch way back ... noise comes from the colour content so if you spit the photo into its LAB or HSL content [ because I do not have LAB ] and just sharpen the L componant you sharpen without noise and then recombine the layers.
Left half of this crop was treated ... I cannot see much difference but maybe the hyper critical can ....

Have not done this for years now prefering the simpler 'sharpen more' or just 'sharpen' ... but then I rarely notice noise.

[OzarkAggie]

While I often use high pass sharpening, and I also have the Topaz collection, you can accomplish the same thing with the standard noise filter. Reducing noise in a high pass layer just eliminates the sharpening of noise in the image.

To a limited degree you can also use Unsharp Mask by raising the Threshold to eliminate unwanted sharpening.

I particularly like high pass for architecture and brick structures like the attached image.

[tommcana]

Sharpness is good it's printing design is also good.

[DanK]

This and a related post by James inspired me to try something similar using LR and photoshop, but I put it in the wrong forum. If you are interested, look for Cactus: PP experiment in the nature and architecture forum. I have a brief explanation of what I did. C&C welcome as always.

[Shadowman]

I haven't tried the Topaz method yet, but NIK Dfine2 has a similar noise reduction module (luminance/chrominance) that does similar enhancement. I've been tinkering with it based on information from this thread.

[John 2]

I'm finding that the advantage of the Topaz De-Noise module is that it seems more aggressive than some others - e.g. Imagenomic. Some images need it. As a sharpening method though, I'm getting to like it basically because it is kinder to heavily cropped shots.