Why I hate frequency separation

[Isedo]

Hi guys, have you noticed that frequency separation become some kind of "overused"technique in skin retouching?
Since it's out, and more in these days, everyone is teaching and using FS. It makes me feel like the new HDR when everyone just use it and use it and use it.

Do you know what i mean? It's an awesome technique but it's "to much" out there. It'a technique used for many years right now and still people use it as a "innovative" way to retouch skin....

It's quite boring...what do u think about?

[byRo]

Re: Why I hate frequency separation

As in many things, the problem is not the tool, but what you do with it.

You can do great things with frequency separation techniques but you need to have some understanding of how they work in order to get the best results.

Problem is, many people on seeing a technique such as this, think that they can blindly just slap it on and automatically achieve perfect results.

If you look at the articles promoting the "FS" technique you will find lots of "Wow!" and very little warning to apply it carefully and in moderation.

[Isedo]

Re: Why I hate frequency separation

Hi byRo,

yes its exactly what I mean. Agree with u man.
Seems like for now, by the way, this is the most popular technique out there. The good old times spending 10 hours in doing d&b are quite gone :-D

What do u think? Is there anything better for now than FS + the middle layers to clean uo the skin, for skin retouching?

[skoobey]

Re: Why I hate frequency separation

It's nothing new and has been used in 3d modeling for years.

It doesn't replace DnB, it compliments it.

Doing local adjustments will never be replaced.

You don't clean skin by separating images into frequency, you shoot good skin if you need to show good skin in the image.

Everything from cloning, healing, dodging and burning on the layer, dodging and burning on separate adjustment layers, selecting, contrast and color adjustments... can be considered skin work. Not to even mention raw conversions.

Newbies think that by paining and flattening contours, or even blurring it, skin looks "high fashion" whatever that is.

[byRo]

Re: Why I hate frequency separation

True, skoobey...

Everything from cloning, healing, dodging and burning on the layer, dodging and burning on separate adjustment layers, selecting, contrast and color adjustments... can be considered skin work.

There is no quick fix or "killer app", just a selection of tools that you need to know how to use and when to use.

Or, in other words "I suppose it is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail" [Abraham Maslow:1966]

[Isedo]

Re: Why I hate frequency separation

Totally agree with u guys. But I must admit that the FS did a great job in speeding up the whole process.

Skoobey for what it was used in 3d?

[byRo]

Re: Why I hate frequency separation

I think he's talking about Bump Maps.
You create a "low-frequency" model and then apply the high-frequency "bumps" as a separate texture.

[typiac]

Re: Why I hate frequency separation

For me, using only the dodge and burn tools is just too long to retouch everyday for everybody. Using DB to complete the frequency separation is a good way, specially when the skin isn't perfect. 30min for fashion and 2 hours for beauty, that's my personal limit to stay good and produce with a good rythme.

[skoobey]

Re: Why I hate frequency separation

@Isedo simulating texture.

[shumicpi]

Re: Why I hate frequency separation

There is a problem high pass filter in the FS technique. When it is used to separate the image into high and low spatial frequencies, the results are inaccurate. In other words, after the separation image data is slightly skewed, so it is required to compromise the quality of the outcome before you even begin retouching.

[Isedo]

Re: Why I hate frequency separation

Ah ok, bump map yes, i learned that it's by the way just a black and white version of the texture it self. How the FS is used in this process?

I agree with Typiac, thats the same workflow if mine. FS is a real time saver for sure.

[byRo]

Re: Why I hate frequency separation

.... i learned that it's by the way just a black and white version of the texture it self. ...

Not really..
The 3D bump map serves exactly the same purpose as the FS High Part, It keeps the fine texture separate from the overall shapes and colours.

If I still remember how to attach images, you should find two examples here. One is a FS High Part and the other a 3D Bump Map. I think you'll see that they are pretty much the same thing.

In fact I sometimes think that I could apply adapted and resized 3D Bump Map images to faces that have lost all skin texture - thus "inventing" a missing FS high part.

Rô

[skoobey]

Re: Why I hate frequency separation

There is a problem high pass filter in the FS technique. When it is used to separate the image into high and low spatial frequencies, the results are inaccurate. In other words, after the separation image data is slightly skewed, so it is required to compromise the quality of the outcome before you even begin retouching.

You just don't know how to blend it.

After you've done you adjustments, to affect only the necessities, you copy high low and band pass layers, merge them, set the resulting layer to difference use threshold to make a selection, use it as a mask or simply delete the unused bit of the layer. But... keep those separated passes in a new file just in case.

[mistermonday]

Re: Why I hate frequency separation

There is a problem high pass filter in the FS technique. When it is used to separate the image into high and low spatial frequencies, the results are inaccurate. In other words, after the separation image data is slightly skewed, so it is required to compromise the quality of the outcome before you even begin retouching.

If you use the HP command in PS it is inaccurate. You see the largest degradation in the highlights. However, if you use the Apply Image command to create the HF layer, it is 99.999% accurate and visually it is impossible to tell the difference if you toggle on/off the separated layer group above the original unseparated layer.
Cheers, Murray

[skoobey]

Re: Why I hate frequency separation

It is asaccurate, it is just doing a different calculation.