[Hacker]

A few weeks ago you may remember I wrote this quickie on high pass sharpening and it got me thinking if there were any other ways of sharpening.

I started tinkering with USM again after reading one of Scott Kelby's books and as such I have now written some actions to use on various types of pictures, by writing the actions it saves a lot of time when processing shots and it makes it easier and less time consuming when experimenting.

For the following images go to Filter > Sharpen > Unsharp mask and apply the following settings:

Portraits
Amount 75%
Radius 2
Threshold 3

Moderate sharpening (good for buildings)
A 225%
R 0.5%
T 0

Maximum sharpening (good for images with well defined edges
A 65%
R 4
T 3

All purpose
A 85%
R1
T4

Web sharpening (do this before resizing )
A 400%
R0.3
T0

These settings are not set in stone and it will pay to experiment but having these to hand as actions will significantly increase your workflow speed.

I also came across another method called Luminosity Sharpening, so called because it only applied to the luminosity of the image (the details areas) and not the colour.

This steps for Luminosity Sharpening are:

Filter > Sharpen > Unsharp mask - Amount 120%, Radius 1.0, Threshold 3, click OK.

Go to Edit > Fade Unsharp Mask and from the Mode drop down menu choose Luminosity.

This is a comparison image I was working earlier in Lightroom and it gave me the perfect opportunity to see a before and after shot using this method (the 'after' shot is on the left) and I must say I really like it, it's early days but I think it would be great for weddings, portraits etc.

[Charlotte]

My usual settings are :

A (variable, btw. 50% and 250%)
R 1
T 0

Doesn't increasing the threshold lessen the effective sharpening? i.e. Why not leave T on 0 and just increase the amount Never really having bothered with the threshold, I'd be enlightened to hear the answer

Your 'Maximum Sharpening' settings are completely different to what I use; I will try yours + see how it comes out Hacker

Yep, your example does look good.

There's another method of sharpening I've used a few times, but not often so I still have to follow the instructions It has good results, so I'll dig it out + post it as well

[_MB_]

Low threshold would sharpen everything, higher threshold would leave areas of similar tones alone - so an already clear edge would be sharpened whereas a less clear edge (i.e. tones on and behind more similar) would not be sharpened.

[Charlotte]

I may be having a blonde moment, but I still don't get it

In particular, what does this mean exactly : "(i.e. tones on and behind more similar)" ?

[Summerleft]

I am stuck with 'the gimp' at the minute, and spent about 20mins last night trying a sharpening technique, however it all came out pink! now may try again as i have suspicions it was the vodka I had but its still not as easy as it looks.

[silkstone]

That's very useful, Hacker - thanks.

For those using Paint Shop Pro, there's a box you can tick in the USM dialogue to select sharpening on Luminance only. I do this by default as it tends not to exaggerate any chroma noise.

[silkstone]

Originally Posted by Summerleft

I am stuck with 'the gimp' at the minute, and spent about 20mins last night trying a sharpening technique, however it all came out pink! now may try again as i have suspicions it was the vodka I had but its still not as easy as it looks.

Try Filters > Enhance > Unsharp Mask and then use the values suggested. Unfortunately there isn't a 'Luminance Only' option.

[Summerleft]

Actually there is silkstone but its a right faff about face to get there, heres the tutorial i tried to use lol there are two ways no 1 being sharpen only the luminosity channel.

GIMP - "Smart" Sharpening

[silkstone]

Good 'eavens! No problem there then.

[_MB_]

Originally Posted by Charlotte

I may be having a blonde moment, but I still don't get it

In particular, what does this mean exactly : "(i.e. tones on and behind more similar)" ?

Sharpening is all based on enhancing contrast yeah? Having a very low threshold means pixels next to each other that are similar, ie contrast is low, will have sharpening applied at the level and radius set in USM. Having a high threshold means pixels next to each other that are similar will not have the sharpening applied, however pixels where the difference in contrast is greater than the threshold will be sharpened.

[Charlotte]

Aaahhh, gotcha, thanks MB