My sharpening experiment

[PrimeTime]

I've been doing alot of reading on sharpening photo's, and how sharpening adds noise to a photo. I tried a new way and can't believe the difference. I'm using a layers mask with edge detect to sharpen. It only sharpens the edges , which keeps the noise down. You can also turn the sharpening up to an insane level.

The first one is sharpened with a unsharp mask. Notice all the noise in the background and flower.




Now the new way................no noise, just sharp.




What do you think? I'm going to try another way soon that uses the highlight channel and see how that works.

[dcclark]

Looks like you lost a significant amount of detail in the flower petals -- they look smudged and blurred. What technique exactly did you use?

[vsa]

I won't think anything before seeing a comparison of two versions of same image.

[dcclark]

Originally Posted by vsa

I won't think anything before seeing a comparison of two versions of same image.

Good point. I hadn't realized that those are similar images, but not the same! PrimeTime -- could you apply the same effect to the same image and post the results?

[PrimeTime]

Originally Posted by dcclark

Looks like you lost a significant amount of detail in the flower petals -- they look smudged and blurred. What technique exactly did you use?

These are actually 2 different pics of similar flowers, and I think i added some noise reduction in the raw photo to start with( maybe too much, because your right i did loose a little detail in the flower petal). I was kind of concentrating on the sharpening process(since it is new to me ). The main thing i noticed is the noise reduction of the background, huge difference. Here is another example ( again i wasn't paying too much attention to other processing, mainly on the sharpening)

These are 2 different photo's also--i should have used the same one's

Sharpened with unsharp mask


Sharpened the new way



You can see a huge difference in the background and the sharpness of the fence.


I used gimp ................Added a Layer mask--Filter...edge detect...edge set slider between 2 and 4 depending on how pronounced the edges are.--Gaussian blur set between 8 and 14 depending on edges--Curves...make darks darker and lights lighter (just a good S shape) -- click off mask and click on layer and sharpen with unsharpen mask........you can drive the sharpness up to an insane level because it's only sharpening the edges and softened by the blur.

[Samanax]

Originally Posted by vsa

I won't think anything before seeing a comparison of two versions of same image.

I agree...gotta see the same image with the different sharpening techniques applied, not 2 similar images.

Personally, I don't care for the new sharpening technique from what I'm seeing here...the new technique seems to make the subjects in the pictures look like plastic.

[wulf]

There is still a lot of difference between those pictures apart from the sharpening - cropping for one thing and I suspect some other manipulation too.

Could you give a demo where the only difference is the sharpening? As an example, here is a sequence based on my favourite high pass sharpening technique:

Crop, straight from camera, no sharpening



2px blur



5px blur



10px blur



If you have a tabbed browser, view each in a different tab and you will see the differences as you switch between them. FWIW, I think the 2px blur or 5px blur work best here. However, results depend very much on the size and content of the image - sharpening seems best as a final step after any resizing.

Wulf

ps. The original shot can be seen on Flickr

[PrimeTime]

OK , i will do a pic tonight(the same pic), with the same level of sharpening , both ways, so you can see the difference. The reason the pics look a little plasticy is because this was the first time i tried it and i CRANKED the sharpening up 6 times(and still no halo) what i normally do. If anyone is familiar with gimp, i had the sharpening set at radius 1.0 and amount 6.75, which is way too much but i wanted to see what the results were. If i would have done that the old way, the sharpness would have completely destroyed the pic and added alot of noise.

Wulf.....thank's for the tip. I'll try it that way also.

[PrimeTime]

Ok , you be the judge................first pic is edited exactly the same as the second except the first was sharpened with unsharp mask set at radius 1.0 and amount 0.80. The second is sharpened with edge sharpening /using an unsharp mask set at radius 1.0 and amount 2.25. After viewing it at 200% i backed the opacity slider down a little bit, so it is prob. sharpened about 2x the amount of the first. Another thing i like about this is if there is an area that isn't sharp enough or too sharp , you can go back into the mask and paint it in to fix it.

I think the second pic is clearly sharper with less noise...........if you zoom in you can see easier.


Unsharpen mask



Edge sharpening /unsharpen mask


So far I like it.............i don't have to sharpen it more than before, but i can with no halo's or more noise. Oh yea, please take into consideration this is only the 4th picture i did this on, so cut me a litte slack

[wulf]

The second picture is definitely sharper without unwanted artifacts - in fact, it takes a bit of time to start spotting the differences, even comparing directly between them!

Edge detection based sharpening is similar to the high pass approach I like to use, as it only affects areas of high contrast. Have you tried the high pass approach? I switched to it after a long period of using a method to the above because I found it quicker and more controllable.

Wulf