Multipass Sharpening

[jsachs]

I always do coarse and then fine sharpening. If you do them in the other order, my guess is that the local contrast enhancement will exaggerate the fine detail sharpening more than the other way around but probably the difference will be subtle.

[tomczak]

which single slider would you use to get a quick fine tune as I rush through my 100

I think that the Blur Threshold slider would be most useful. It in effect excludes major contrasty edges from sharpening as you move it from right (all sharpened) to left (nothing sharpened).

It's similar in functionality to the right set of sliders under the Advanced Sharpen roughness histogram. Often, if not excluded, those major edges stick out being over sharpened - or in other words, excluding them allows for more aggressive sharpening of less contrasty details elsewhere and the picture may benefit from it.

p.s. Sharpen Threshold is a little like the left Advanced Sharpen histogram sliders.

[tonygamble]

Thanks Majiec,

And that is on Jonathan's Pass 2 not Pass 1?

T

[tomczak]

I suppose protecting major edges may be most beneficial for actual sharpening in Pass 2, but probably also useful in large radius contrast enhancement of Pass 1, though to lesser degree?

[tomczak]

Snag for me is I am a batch man and don't have the time to do that level of adjusting on my first run.

It's actually useful for batches - the idea is to choose the 'best' parameters for the batch. The advantage of setting the Sharpen Factor to zero and replacing sharpening with blurring on preview during the adjustments is that blurring is easier to notice and thus adjust properly.

[tonygamble]

Snag for me is I am a batch man and don't have the time to do that level of adjusting on my first run.

It's actually useful for batches - the idea is to choose the 'best' parameters for the batch. The advantage of setting the Sharpen Factor to zero and replacing sharpening with blurring on preview during the adjustments is that blurring is easier to notice and thus adjust properly.

Are you saying that the only two sliders I need to alter are the blur ones? If so, in which order please.

[tomczak]

I start with my null settings (earlier in this thread) which don't affect the image at all. Then I proceed as follows - the description takes longer than actually doing it. Just remember that as long as the Sharpen Factor slider stays at zero (or less than 1) what's appear blurred will be eventually sharpened and what is not blurred will stay unsharpened and will not be graced with possible halos.

1. Increase Blur Radius. Blur what you want to sharpen and a little more (which will be dialed down in the next step).
2. Decrease Blur Threshold. This 'unblurs' major edges, thus preventing unseemly halos on them when actually sharpened.
3. Increase Sharpen Factor to more than 1. Overdo it a little - some oversharpening halos will be reduced in the next step
4. Decrease halos with Halo Limit slider. In many images the white halos are more objectionable than dark halos and need to be cut down more.

Optionally, I increase the Sharpen Threshold a little in the end to exclude the finest details like grain or noise from sharpening, but that needs to be done delicately if you want the image to look naturally.

If I do it in this fashion, I can understand better how each of the sharpening parameters affect the output and I think it makes it easier to figure out what to adjust to make corrections if I don't like the result.

p.s. The adjustments are not that different functionally from the Advanced Sharpen excluding finest and coarsest details on the roughness histogram. Also, you could do those adjustments in the sharpen mode (i.e. with the Sharpen Factor > 1) but I find changes in blurring easier to detect than changes in sharpening when doing the adjustments.

[jsachs]

If you are going to adjust just one slider, the Blur Threshold for Pass 1 has the most effect.

[tonygamble]

Maciej,

I am trying but struggling.

My first problem is dealing with the white/black sliders for Halo Limit and Sharpen Threshold. If I need to slide them both I struggle with my cursor.

I there any way I can make the whole Multipass Sharpen control window permanently larger. That little preview window is so important that I could do with it using half my screen.

This is a really noisy shot and I need this amount of preview.

Wed 1.jpg (170.21 KiB) Viewed 3029 times

[tonygamble]

M,

Isn't using that Show Differences a key to seeing what is happening?

T