Forums > Digital Art and Retouching > The High Pass / Imagenomic Portraiture Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

I was asked in another thread about the difference between 'Inverted High Pass' & related techniques and Imagenomic's Portraiture plugin.  And as I'd have likely been harangued for making things too technical in posting there, I wanted to start a new discussion on the similarities and differences.


The short (less technical) version: Portraiture is a workflow tool which does the same thing as 'Inverted High Pass' within a structured UI and with some automatic masking features, allowing other adjustments to be rolled into that same masked area.

The short (quite technical) version: Portraiture can be thought of as a defined-band spatial frequency equalizer with a strong color-based masking system to limit edges and effect area.

The long version: When you use the "Inverted High Pass" techniques (hereafter IHP), you are in effect selecting a band of spatial frequencies which you want to minimize (or 'attenuate') within an image.  You then mask that into the skin-tone area through your preference of selection and masking techniques, adjust your opacity, etc. until you get a result you like.  You might even go so far as to use separate radii (frequencies) for different areas of the skin to get a more pleasant aesthetic result.  Many people use actions and / or scripts to automate large parts of this process - some of which are commercialized and available for purchase.

Portraiture offers a different way of doing much the same thing - it helps you to create a mask in a manner very much akin to the Select Color tool in PS, and then to refine that mask as you see fit.  You have the ability to adjust the amount of smoothing which takes place over details of different sizes - just like in IHP techniques where you are choosing your radii and opacities; it's just choosing the radii for you based on the image size which you told it you are using.  And then of course you can make color, contrast, saturation, etc. adjustments to the selected skin areas as you see fit.

So, when I say that Portraiture is above all a workflow tool, I really mean it.  It does what Christy Schuler does (actually, it does it better); it does what some of our esteemed membership do on their images; it even does (again, better) what was recommended recently in an article in Photoshop User by one of the most esteemed names in retouching.  It just makes it easier for the user to do it, and opens a technique to populations of users who might never know what a spatial frequency is.

For the hardcore geeks - to be sure, Portraiture isn't likely using Adobe's internal filters to do all the work - it would be rather cumbersome for them to be doing so programmatically.  But I'm quite confident that it is using a Gaussian (or more likely a fake Gaussian) kernel to do the separating, and more importantly that it is not losing data in a 'High Pass Sucks' sort of way.

Feel free to ask questions - I'm sure that I've left a lot out as I hurriedly type this lest Krunoslav think I'm blowing him off smile.

Edit: It's also important to note for the control freaks that you can't manually set the radii which are going to be used - these are controlled based on the image size you select and the 'detail size' whose slider you adjust.  Maybe if everyone asks really nicely though they'll add an 'advanced' feature for you where you can pick your own.

Jul 15 10 01:06 pm Link

Retoucher

Carl Davis Retouch

Posts: 42

Telford, England, United Kingdom

thanks for taking the time to post this. I played with portraiture at the start and recommend it to people who dont want to spend to long retouching. But for me it gave a bit of a waxy feel to the skin, even dialed down.  I think its to do with the blur under the high pass sharpening or something, yeah im not very technical smile

But its a great tool that has its purposes

Carl

Jul 15 10 01:22 pm Link

Retoucher

Krunoslav Stifter

Posts: 3884

Santa Cruz, California, US

Well written! smile For the sake of learning, I hope this thread won't be trashed.

I might throw in some more advance tips for portraiture use, later on! wink

I would just like to say, that it's about the users abilities and the final result. Everything else is just tools, including Photoshop itself.

Jul 15 10 01:27 pm Link

Photographer

Rafael Telles

Posts: 1375

Brampton, Ontario, Canada

Krunoslav-Stifter wrote:
I might throw in some more advance tips for portraiture use, later on! wink

I would just like to say, that it's about the users abilities and the final result. Everything else is just a tools, including Photoshop itself.

Can't wait to read your tips Krunoslav. In my workflow I have several steps in Portraiture, for some images 1 or 2 Portraiture layers do the trick for others I do as many as 5; this is because I do a lot of tiny corrections at a time for specific colour ranges.

I used to do the IHP all the time before the newest version of Portraiture came out, but the newer version gives so much control that I find it does thesame job with way less steps on my side; the masking alone is a time saver for me.

Jul 15 10 02:02 pm Link

Retoucher

Peano

Posts: 4106

Lynchburg, Virginia, US

Very nicely written, Sean.

Krunoslav-Stifter wrote:
I might throw in some more advance tips for portraiture use, later on! wink

Please do!

Jul 15 10 03:18 pm Link

Photographer

Internos Photography

Posts: 546

San Jose, California, US

What I like about Portraiture over the IHP method is that it is so much faster.  You get 3 levels of granular control for smoothing (fine, medium, large) and a threshold level for all 3.  The enhancements that come as part of it are also useful and can be used for quite a variety of purposes.  It is a very versatile tool for what it does.

What I don't like is that it does not work well with receiving a masked selection even though it is designed for one.  If I start with a masked selection (as I would with IHP), the edge ends up needing a lot of work and I found what works best is to use the tools "Create new layer" output option and apply a layer mask to that.

Jul 15 10 04:09 pm Link

Retoucher

Peano

Posts: 4106

Lynchburg, Virginia, US

Internos Photography wrote:
What I don't like is that it does not work well with receiving a masked selection even though it is designed for one.  If I start with a masked selection (as I would with IHP), the edge ends up needing a lot of work and I found what works best is to use the tools "Create new layer" output option and apply a layer mask to that.

I'm just wondering, why do you not use the masking function in Portraiture and then mask the result further, if needed?

Jul 15 10 05:43 pm Link

Photographer

Sean Armenta

Posts: 1560

Los Angeles, California, US

quite possibly the most intelligently written post on MM ever.

and not just because of the big words.

Jul 16 10 12:56 am Link

Retoucher

K o r a y

Posts: 251

Ankara, Ankara, Turkey

Has anyone ever thought about using the new hdr adjustments instead of highpass on an inverted layer? big_smile

I personally am not against any plugins at all but portraiture is not the kind that I'll ever need.

Jul 16 10 01:15 am Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Carl Davis Retouch wrote:
But for me it gave a bit of a waxy feel to the skin, even dialed down.  I think its to do with the blur under the high pass sharpening or something, yeah im not very technical smile

At a guess, I suspect this has either to do with the detail sizes which you're employing being improper for the image itself (try changing the Image Size setting), or that the original material just doesn't have enough detail in it to support smoothing (one of the program limitations is in texture replacement).

Peano wrote:
Very nicely written, Sean.

Thank you sir.  I may be a grunt, but I am occasionally a polysyllabic one smile.

Peano wrote:
Please do!

+1

Internos Photography wrote:
What I don't like is that it does not work well with receiving a masked selection even though it is designed for one.  If I start with a masked selection (as I would with IHP), the edge ends up needing a lot of work and I found what works best is to use the tools "Create new layer" output option and apply a layer mask to that.

In theory it should be fine, but the way that the PS plugin architecture works there are a number of places where this could get snarled up hmm.  Does it have the same problem with a feathered selection vs. a 'hard' selection?  And are you applying any adjustments (contrast, brightness, saturation, etc.) besides the smoothing?

Peano wrote:
I'm just wondering, why do you not use the masking function in Portraiture and then mask the result further, if needed?

Delineation of hair / not-hair, jewelry / not-jewelry, etc. areas could be advantageous to the algorithm and if successful minimize the inappropriate mixture of image areas - particularly when colors are reflecting (and therefore blending) or are just 'near' one another in the first place.

Sean Armenta wrote:
quite possibly the most intelligently written post on MM ever.

and not just because of the big words.

You must not have seen the iPhone4 color calibration thread wink.

Only teasing - that's a high compliment from you and much appreciated.

K o r a y wrote:
Has anyone ever thought about using the new hdr adjustments instead of highpass on an inverted layer? big_smile

I personally am not against any plugins at all but portraiture is not the kind that I'll ever need.

I have, but haven't spent the time to find a reasonable way of turning it into a feasible workflow.  Have you come up with something akin to how we made IHP a 'Smart Filter', or is it still fairly cumbersome to work with?

Jul 16 10 03:03 am Link

Digital Artist

Koray

Posts: 6716

Ankara, Ankara, Turkey

It looks cumbersome and involves alot of inverted guessing but some experimenting may lead to a look rather than a workflow smile

Jul 16 10 04:43 am Link

Retoucher

Versiontwo Fine Art

Posts: 236

Melbourne, Victoria, Australia

Krunoslav-Stifter wrote:
I might throw in some more advance tips for portraiture use, later on! wink

um ive seen you say this and things simular in other threads and then never live up to your promises, so it will be interesting to see if you actually offer advice this time instead of acting like you know it all already.

Jul 16 10 04:47 am Link

Retoucher

Natalia_Taffarel

Posts: 7665

Buenos Aires, Buenos Aires, Argentina

aaronv2 wrote:
um ive seen you say this and things simular in other threads and then never live up to your promises, so it will be interesting to see if you actually offer advice this time instead of acting like you know it all already.

meow

Now

IMO (for the mean crowd)
For Beauty Work
When you use the IHP with the 1/3 rule - selectively (different radius for different parts of the face ) You never compromise the "tightness" of the skin. You can't do that with portraiture unless you do it once/mask it to affect one part of the skin and not the whole face, then run it again and do the same, and again, and again (Running the plug in several times is a lot more time consuming than doing it manually) - Also - Portraiture is limited in the amount of radius (When used on a 8000 px wide image it falls short)
With the IHP (always used with the 1/3 rule) you can select the right radius for each area, mask it and paint and it's a lot more accurate since you're NEVER loosing the "good" texture, only the bad one if you're choosing the radius right.

Just my 2 cents

Jul 16 10 05:29 am Link

Photographer

DW DALLAM PHOTOGRAPHY

Posts: 1385

Arcata, California, US

I use this tool but it took me a while to adjust it where my retouches look natural. Mainly, since I want to get the job done as fast as possible,  I'll start with the default mode and add my adjustments in house, then import to PS and use grain, opacity, and masking to finish the job. I created an action to do most of it. Then I just tweak for different light and faces. Takes me about 45 seconds to do an image--where the model already has decent skin.

Jul 16 10 05:38 am Link

Photographer

Mickle Design Werks

Posts: 5960

Washington, District of Columbia, US

SRB Photo wrote:
I was asked in another thread about the difference between 'Inverted High Pass' & related techniques and Imagenomic's Portraiture plugin.  And as I'd have likely been harangued for making things too technical in posting there, I wanted to start a new discussion on the similarities and differences.


The short (less technical) version: Portraiture is a workflow tool which does the same thing as 'Inverted High Pass' within a structured UI and with some automatic masking features, allowing other adjustments to be rolled into that same masked area.

The short (quite technical) version: Portraiture can be thought of as a defined-band spatial frequency equalizer with a strong color-based masking system to limit edges and effect area.

The long version: When you use the "Inverted High Pass" techniques (hereafter IHP), you are in effect selecting a band of spatial frequencies which you want to minimize (or 'attenuate') within an image.  You then mask that into the skin-tone area through your preference of selection and masking techniques, adjust your opacity, etc. until you get a result you like.  You might even go so far as to use separate radii (frequencies) for different areas of the skin to get a more pleasant aesthetic result.  Many people use actions and / or scripts to automate large parts of this process - some of which are commercialized and available for purchase.

Portraiture offers a different way of doing much the same thing - it helps you to create a mask in a manner very much akin to the Select Color tool in PS, and then to refine that mask as you see fit.  You have the ability to adjust the amount of smoothing which takes place over details of different sizes - just like in IHP techniques where you are choosing your radii and opacities; it's just choosing the radii for you based on the image size which you told it you are using.  And then of course you can make color, contrast, saturation, etc. adjustments to the selected skin areas as you see fit.

So, when I say that Portraiture is above all a workflow tool, I really mean it.  It does what Christy Schuler does (actually, it does it better); it does what some of our esteemed membership do on their images; it even does (again, better) what was recommended recently in an article in Photoshop User by one of the most esteemed names in retouching.  It just makes it easier for the user to do it, and opens a technique to populations of users who might never know what a spatial frequency is.

For the hardcore geeks - to be sure, Portraiture isn't likely using Adobe's internal filters to do all the work - it would be rather cumbersome for them to be doing so programmatically.  But I'm quite confident that it is using a Gaussian (or more likely a fake Gaussian) kernel to do the separating, and more importantly that it is not losing data in a 'High Pass Sucks' sort of way.

Feel free to ask questions - I'm sure that I've left a lot out as I hurriedly type this lest Krunoslav think I'm blowing him off smile.

Edit: It's also important to note for the control freaks that you can't manually set the radii which are going to be used - these are controlled based on the image size you select and the 'detail size' whose slider you adjust.  Maybe if everyone asks really nicely though they'll add an 'advanced' feature for you where you can pick your own.

Excellent write up Sean. You do such a great job of explaining the geek of Photoshop in an accessible way.

You just confirmed what I suspected about the Portraiture plug-in and why I use it. I could care less about whether it uses a blur or IHP, all I want is a way to smooth the skin quickly without having to do a ton of manual work and leave the other details of the image alone. Portraiture accomplishes this very well for me.

Jul 16 10 05:47 am Link

Photographer

Dragon Ink - Sean William

Posts: 1061

Hackettstown, New Jersey, US

Krunoslav-Stifter wrote:
I might throw in some more advance tips for portraiture use, later on! wink

I would really be interested in more advanced techniques using this plugin.  I have my own workflow, but would really like to see how it might be used in other ways.

Jul 16 10 09:36 am Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

As part of a side conversation I was having with another forum member, I spent a bit of time looking more into the masking which Portraiture does and would like to offer a few additional thoughts for those who are considering using it and particularly those who might have enough sway with the company to propose a few changes.

The Way Things Are - I was happy to see that I was correct in my previous suggestion that its masking and smoothing routines treat the selected area in a manner very analogous to using a separate layer consisting only of the skin areas in PS with the 'Preserve Opacity' option turned on.

What's Good About It - This is very advantageous in that when the frequency separation takes place, the algorithm is prevented from sampling the 'non-skin' areas such as hair, clothes, jewelry, etc. and thereby 'contaminating' the skin with non-skin colors & texture.  As such, the result almost appears as good as some of the more advanced and edge-aware operations like surface blur, median, etc.

Whats Wrong With It - Nothing comes for free, and no implementation is perfect.  Iternos was quite right that the plugin can behave quite oddly when it's fed a selection vs. giving it the whole layer.  Not only does it give a different result than without a selection [even in cases where it should be the same result], but it behaves very strangely when any of the creative effects are applied in conjunction with the normal smoothing [quite likely a logic error in which image regions to consider for those portions of the code].

Perhaps more problematic, though, is that the masking methodology has some very real and very hard limits to its capabilities.  Simulation tests showed that in cases where a model might need a heavy dose of smoothing, it's not hard to introduce banding through the masking procedure [probably a precision limit in the way the mask is calculated].  And when the integration with pre-selected areas isn't working well, this makes it all but impossible to only work on the image areas which you really want to.

Making It Right - It would be quite easy to introduce two changes in Portraiture to fix all of the above and leave the (increasing) competition in the dust.  And more importantly, give their obviously very loyal customers more control and better results.

First, introduce an 'Advanced' or 'Expert' checkbox in the Preferences dialog which allows the user to enter their own frequency radii for the Fine / Medium / Large detail sliders - even better if the limits of the sliders normalize to the actual % values of the band's presence [making Portraiture attractive to those looking for a spatial frequency equalizer].

Second, much in the way that Lightroom and Aperture have their adjustment brushes, allow the user to directly paint in and erase areas of masking, using the original selection which PS provides the plugin as the initial 'painted' mask.  This mask would could then be (optionally) intersected in high numerical precision with the color range selection made by the tool as it normally does [default should probably be to use the color range, adding in the user mask as an option].  If that last sentence didn't make any sense to you, don't worry - it should to the programmers and simply means that you'd end up with full control of what is skin and isn't skin, giving you a perfect result smile.

Does it Matter? - It's been pointed out to me that the above might come off as rather damning on the whole of Portraiture.  Let me be clear: it's not meant as such - the above are simply the elucidation of the plugin's limitations such as relate to the difference between itself and IHP techniques.  That it also represents opportunity for Imagenomic to expand its market base is true, but is an aside to the actual point of the discussion.

Jul 17 10 08:03 am Link

Retoucher

Peano

Posts: 4106

Lynchburg, Virginia, US

SRB Photo wrote:
As part of a side conversation I was having with another forum member, I spent a bit of time looking more into the masking which Portraiture does and would like to offer a few additional thoughts for those who are considering using it and particularly those who might have enough sway with the company to propose a few changes.

I don't have any sway, but Imagenomic has a Suggestions forum, so I posted a link to this thread. You might keep an eye on that and perhaps chime in if you see a good opening.

Jul 17 10 01:20 pm Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Peano wrote:

I don't have any sway, but Imagenomic has a Suggestions forum, so I posted a link to this thread. You might keep an eye on that and perhaps chime in if you see a good opening.

Thanks for letting me know; I'll check up on it!

Jul 17 10 01:36 pm Link

Photographer

Julian Marsalis

Posts: 1191

Austin, Texas, US

Natalia_Taffarel wrote:

meow

Now

IMO (for the mean crowd)
For Beauty Work
When you use the IHP with the 1/3 rule - selectively (different radius for different parts of the face ) You never compromise the "tightness" of the skin. You can't do that with portraiture unless you do it once/mask it to affect one part of the skin and not the whole face, then run it again and do the same, and again, and again (Running the plug in several times is a lot more time consuming than doing it manually) - Also - Portraiture is limited in the amount of radius (When used on a 8000 px wide image it falls short)
With the IHP (always used with the 1/3 rule) you can select the right radius for each area, mask it and paint and it's a lot more accurate since you're NEVER loosing the "good" texture, only the bad one if you're choosing the radius right.

Just my 2 cents

Rule of IHP 1/3???? Can I get some clarity on the subject? Break the face up into zones and selectively mask each from the other? now I am curious of this work flow. I may do multiple frequency separation on an image but never always lol.

Sep 01 10 11:23 am Link

Retoucher

ManoDeGato by MaryTere

Posts: 283

Guadalupe, San José, Costa Rica

bookmarking this, seems like a thread I might want to be checking back smile

Sep 01 10 11:34 am Link

Retoucher

ManoDeGato by MaryTere

Posts: 283

Guadalupe, San José, Costa Rica

Krunoslav-Stifter wrote:
Well written! smile For the sake of learning, I hope this thread won't be trashed.

I might throw in some more advance tips for portraiture use, later on! wink

*waits patiently for Krunoslav's tips and also bumps thread*

Oct 09 10 10:26 am Link

Retoucher

Pictus

Posts: 1262

Teresópolis, Rio de Janeiro, Brazil

ManoDeGato by MaryTere wrote:
*waits patiently for Krunoslav's tips and also bumps thread*

Me too, curious to know what he got hidden under the hat... lol

Oct 09 10 12:48 pm Link

Photographer

Jerry Bennett

Posts: 2223

Philadelphia, Pennsylvania, US

Er, can anyone point me to the info about "Inverted High Pass" and this 1/3 rule? Is this a different way to do frequency separation than the original actions in the High Pass Sucks thread?

Oct 09 10 10:46 pm Link

Retoucher

George Thomson

Posts: 698

Concord, California, US

I just read the comments you had here:
http://www.imagenomic.com/forum/showthread.php?t=1916

... so I decided to look into what that company is... to be honest it was not too easy to find out who Imagenomic LLC are...

They are based in Virginia... and I was surprised to find that it is in essence - one person and this is his more or less... a home-business. It looks like he probably has an investment partner, but there are only a couple of staff and it looks like they don't even have an office...
and they have a photographer-consultant: http://www.ericneilsenphotography.com


The answer you got in the form there is not from the developer (so who knows what that person actually understands about the software).

The limitation of the radii as pointed out, hints for implementation using the PS api, and probably this is why Portraiture is not standalone.


needless to say now I feel somewhat bad for starting to make a free alternative to their product Portraiture...

I guess you can make a living out of making software for quick portrait retouch... but looks like you won't get rich =/ ... somewhat disappointing to say the least.

However I have to say for such a small crew they have a good product.

Oct 09 10 10:59 pm Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Photon Mayhem wrote:
They are based in Virginia... and I was surprised to find that it is in essence - one person and this is his more or less... a home-business. It looks like he probably has an investment partner, but there are only a couple of staff and it looks like they don't even have an office...
and they have a photographer-consultant: http://www.ericneilsenphotography.com

I can't say how large the company is, as I don't know the internal structure - I can say that I've met the owner and at one of the developers. Both gave the impression of their positions being full-time, but again I can't verify that.

Photon Mayhem wrote:
The answer you got in the form there is not from the developer (so who knows what that person actually understands about the software).

Agreed - at least the first part. I feel rather certain that he in fact knows little about what he was writing and only skimmed through this material, assuming that it was just another plugin-bashing rant.

Photon Mayhem wrote:
The limitation of the radii as pointed out, hints for implementation using the PS api, and probably this is why Portraiture is not standalone.

Inherently they have to be using the Adobe API / SDK in order to run a plugin at all, but I'm more inclined to believe that they are doing their own pixel processing vs using the PS versions (which, through the SDK is even harder). The radii issue is just one of understanding the wider audience which would be interested in the product and adapting the UI to appeal to that segment.

Photon Mayhem wrote:
needless to say now I feel somewhat bad for starting to make a free alternative to their product Portraiture...

Don't. I warned them above some time ago that segment competition was going to skyrocket. And while I was contacted by a few for consultation, none have bothered to follow through. Yours will hopefully be the wake up call that they need to adapt and improve.

Oct 10 10 07:58 am Link

Retoucher

ManoDeGato by MaryTere

Posts: 283

Guadalupe, San José, Costa Rica

Jerry Bennett wrote:
Er, can anyone point me to the info about "Inverted High Pass" and this 1/3 rule? Is this a different way to do frequency separation than the original actions in the High Pass Sucks thread?

Natalia uses that technique on her hair video here:
https://www.digitalphotoshopretouching. … ir-retouch

Is kind of a  "HPS" with a twist... but I also would like to hear more about it wink

Oct 10 10 09:56 am Link

Photographer

Chris Chua

Posts: 140

Las Vegas, Nevada, US

Natalia_Taffarel wrote:
meow

Now

IMO (for the mean crowd)
For Beauty Work
When you use the IHP with the 1/3 rule - selectively (different radius for different parts of the face ) You never compromise the "tightness" of the skin. You can't do that with portraiture unless you do it once/mask it to affect one part of the skin and not the whole face, then run it again and do the same, and again, and again (Running the plug in several times is a lot more time consuming than doing it manually) - Also - Portraiture is limited in the amount of radius (When used on a 8000 px wide image it falls short)
With the IHP (always used with the 1/3 rule) you can select the right radius for each area, mask it and paint and it's a lot more accurate since you're NEVER loosing the "good" texture, only the bad one if you're choosing the radius right.

Just my 2 cents

Natalia,

Are you referring to the "degrunge" method as seen here?

http://retouchpro.com/tutorials/?m=show&id=213

Also, just wondering your take (and others) on the "Joel Grimes" method as seen here.

http://web.me.com/joelgrimes/Joel_Grime … thing.html

So far my work flow starts out using HP sucks then for skin smoothing I've been using the Joel Grimes method. I've tried substituting the "degrunge" method instead of the Joel Grimes method but noticed that although it seems to be effective, it shows where I've previously cloned/healed (blotches) and I'm not sure why.

Oct 10 10 10:24 am Link

Retoucher

ManoDeGato by MaryTere

Posts: 283

Guadalupe, San José, Costa Rica

Flipmode wrote:
Natalia,

Are you referring to the "degrunge" method as seen here?

http://retouchpro.com/tutorials/?m=show&id=213

If I understand correctly, the idea of IHP is to use the "degrunge" method you're linking, but instead of applying a high pass filter, you do the "apply image" accordingly to the bits of the image (8 bit => substract/scale:2/offset: 128, 16 bit=> add/scale:2/offset:0) to avoid haloing.

Oct 10 10 10:40 am Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Flipmode wrote:
Are you referring to the "degrunge" method as seen here?

http://retouchpro.com/tutorials/?m=show&id=213

Also, just wondering your take (and others) on the "Joel Grimes" method as seen here.

http://web.me.com/joelgrimes/Joel_Grime … thing.html

The 1/3 "rule" has been discussed in a lot of places over the years, and while byRo's tutorial is the oldest mention of it which I've come across, but I'm not sure it can be attributed to him. It has it's plodded and minuses as a technique which I'm happy to discuss technically if there's interest (it'll be ~1wk until I get to a comp to do so, but again will if it's desired).

Joel's technique was good in it's day, but has been supplanted by many which have been discussed here in the interim. Derivations based around a "HPS" technique are a good start.

Oct 10 10 12:04 pm Link

Retoucher

Krunoslav Stifter

Posts: 3884

Santa Cruz, California, US

Julian Marsalis wrote:
Rule of IHP 1/3???? Can I get some clarity on the subject? Break the face up into zones and selectively mask each from the other? now I am curious of this work flow. I may do multiple frequency separation on an image but never always lol.

The IHP (Inverted High-Pass) can actually be used without the High-Pass filter being applied. But instead of HP more accurate method is used. The Apply Image command. You can see it in motion here being displayed by Natalia on the Hair instead of the skin. But the principle and workflow remain the same. You only use the different pixel radius. http://www.digitalphotoshopretouching.c … ir-retouch

To prevent the image looking unnatural or suspicious you would use different radius values on different parts of the skin. One radius for the chest area, different one for the cheek or forehead. And mask it out over the problematic area. Off course, once the effect is applied you can brush it in with lower opacity/flow brush and/or lower the opacity of the layer itself, thus making a more precise correction.

Here is how the potential workflow might looked like. This is manual way of doing it, but I suggest once you are familiar with it to record it as Photoshop action and save yourself valuable time.

Step 1 - Duplicate the background layer or "working" layer, two times. Rename the the first copy as LOW and the second copy as HIGH. You can rename them anyway you want really, but this is more descriptive. At the end you will have to hide or delete that LOW layer anyway.

Step 2 - This step is not mandatory for this technique to work but until you get more experienced and get used to common pixel values, it's a good idea to use it. In the example shown below we need to get rid of the darker patches of the skin that most of the time represent blotchy skin, or some other unfaltering problem. To see what radius we will need to fix that, we can use the High-Pass filter.

You open the High-Pass by going to Filter - Other - High-Pass and you play around with the radius value, until you start to see the areas that represent the problem as circled in red. You set that radius to some number that you can easily divide by three.
In this case that was 48 px. Also the numbers are usually higher than 18 px, unless you want to totally get rid of the details. This applies to portrait or beauty image mostly. Now you don't apply the filter but instead you abort or cancel out of it. We are suing it only as indicator of how much pixel value we must use in our next step. So make sure you remember the value.

http://img254.imageshack.us/img254/8831/slide1dl.jpg


Step 3 - Select the LOW layer and apply Gaussian Blur with the radius of 48 px. In case you have done this many times you can make a pretty good guess of the value and that means step 2 can be avoided.

Step 4 - Select the HIGH layer and go to Image  - Apply Image... As your source select the LOW layer. (That is why we have renamed it, so we can choose it here without the preview.) As for the rest of the setting. Well, that depends on what bit depth are you working on. Here you can see what settings to apply. http://www.modelmayhem.com/po.php?threa … 374&page=1

Step 5 - Still working on the HIGH layer apply 1/3 of the Gaussian Blur radius that you applied to the LOW layer. That would be 16 px Because in the example we used 48 and that divided by 3 is 16. 48/3=16

Step 6 - Invert the HIGH layer by selecting it and pressing CTRL + I

Step 7 - Set the High layer to blend mode of Linear Light

Step 8 - Delete or hide the LOW layer and you will star to see the effect, but it's global and we need to make it local.

Step 9 - Add a layer mask to the HIGH layer by selecting it and pressing the layer mask icon at that bottom of the layer panel. Hold down the ALT key while mouse clicking to get black mask.

http://img297.imageshack.us/img297/6169/sliede2.jpg

Step 10 - Choose you brush and paint with white over the image while the layer mask is selected so you can brush in the effect over the specific area that you want.

Step 11 - You repeat the steps 1-10 with different radius to fix different skin areas, like cheek or forehead.

OPTIONAL:
You can set the whole group of layers, that you used for the image inside one layer group and that way you can easily see before and after and stay organized.

ADDITIONAL NOTES:
This technique is not limited to just skin. It can be used for anything. Things like hair, fabric, background elements etc. It does come with few side effects though. This whole technique produces the effect that reduces contrast of the image. And it increases contrast of the edges, giving you undesired effect in most cases.

So basically you get less contrast where aren't any well defined edges and you get more contrast where the edges are well defined. 

To fix the lack of contrast you can use D&B and paint in the contrast manually or you can use any of the adjustment layers like curves or levels. You can clip them to the HIGH layer and they will honor the mask being used on that layer or you can duplicate the layer mask of the HIGH layer to the Curves layer.

Fixing edge contrast can be done in several ways as well. I think by selecting the skin area or any area that you want to fix before you apply filter at the begging stage should minimize the problem. Or you can be careful and not paint over or near the edges in step 10. I think you can also use Surface Blur instead of Gaussian Blur filter, but it takes longer and I'm not sure how mathematically correct it is.

P.S.
As I have suggested and have been reminded, I will post tips on Portraiture when I secure some more free time.

Oct 10 10 12:19 pm Link

Retoucher

George Thomson

Posts: 698

Concord, California, US

SRB Photo wrote:
I can't say how large the company is, as I don't know the internal structure - I can say that I've met the owner and at one of the developers. Both gave the impression of their positions being full-time, but again I can't verify that.

lets just say there's isn't too much privacy in internet... and I'm pretty confident in this information.
once you find the address, phone numbers (home and cell) the rest of the information is easy to get.

I'm sure it is a full-time, but if I have to guess... the company at best probably makes 200 ~500k / yr.


SRB Photo wrote:
Inherently they have to be using the Adobe API / SDK in order to run a plugin at all, but I'm more inclined to believe that they are doing their own pixel processing vs using the PS versions (which, through the SDK is even harder). The radii issue is just one of understanding the wider audience which would be interested in the product and adapting the UI to appeal to that segment.

well.. yes... I meant to say that they probably rely on the hp/gb functions inside PS, not using their own algorithms. (using proxies for preview should not be that hard... and there is not much point of reinventing the wheel as the functions they use are available in PS)

But if you say it is not the gb/hp, I won't argue. I can't really test it to say for sure.

SRB Photo wrote:
Don't. I warned them above some time ago that segment competition was going to skyrocket. And while I was contacted by a few for consultation, none have bothered to follow through. Yours will hopefully be the wake up call that they need to adapt and improve.

... to be honest working with frequencies to skin-smooth to me is quite inferior to other options.
the other options may get commercial of course... it depends on whether I find a proper company to implement them

but no matter what having free tools should be good for everyone

Oct 10 10 01:45 pm Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Photon Mayhem wrote:
... to be honest working with frequencies to skin-smooth to me is quite inferior to other options.

Please, enlighten us.

Oct 10 10 01:50 pm Link

Retoucher

George Thomson

Posts: 698

Concord, California, US

SRB Photo wrote:

Please, enlighten us.

all in good time

Oct 10 10 02:04 pm Link

Retoucher

ManoDeGato by MaryTere

Posts: 283

Guadalupe, San José, Costa Rica

Krunoslav-Stifter wrote:
The IHP (Inverted High-Pass) can actually be used without the High-Pass filter being applied. But instead of HP more accurate method is used...

(Insert super detailed and awesome mini tutorial here)

Thanks a lot for taking the time to put that together, Krunoslav!! big_smile

Krunoslav-Stifter wrote:
P.S.
As I have suggested and have been reminded, I will post tips on Portraiture when I secure some more free time.

We'll be waiting smile

Oct 10 10 03:53 pm Link

Photographer

Jerry Bennett

Posts: 2223

Philadelphia, Pennsylvania, US

Krunoslav-Stifter wrote:
......
Here is how the potential workflow might looked like. This is manual way of doing it, but I suggest once you are familiar with it to record it as Photoshop action and save yourself valuable time.....

Ah! Ok, Thank You! I'll have to try this and see if I like it better than the action I downloaded off the HPS thread....

Oct 10 10 05:20 pm Link

Photographer

Chris Chua

Posts: 140

Las Vegas, Nevada, US

SRB Photo wrote:

The 1/3 "rule" has been discussed in a lot of places over the years, and while byRo's tutorial is the oldest mention of it which I've come across, but I'm not sure it can be attributed to him. It has it's plodded and minuses as a technique which I'm happy to discuss technically if there's interest (it'll be ~1wk until I get to a comp to do so, but again will if it's desired).

Joel's technique was good in it's day, but has been supplanted by many which have been discussed here in the interim. Derivations based around a "HPS" technique are a good start.

That would be great Sean, if you can do a comparison of some sort with an easy to read write up as you did on this thread. Whenever time permits of course.

Also, the only reason I mentioned it was because I'm reading Gry Garness e-book which mentions the "degrunge" technique so I wasn't sure if it was still relevant in today's practice.

thanks!

Oct 10 10 08:57 pm Link

Photographer

Sean Baker Photo

Posts: 8044

Fairfax, Virginia, US

Flipmode wrote:
Also, the only reason I mentioned it was because I'm reading Gry Garness e-book which mentions the "degrunge" technique so I wasn't sure if it was still relevant in today's practice.

thanks!

It's relevant generally; just not as efficient / high quality as it could be doing it the way that Gry explains it (at least as of the last version of her eBook which I saw). And the 1/3 issue is just a starting point - more on that next week.

Oct 11 10 05:01 am Link

Retoucher

George Thomson

Posts: 698

Concord, California, US

I was just trying to find similar software/plugins that offer "automatic" skin retouch, but so far I found only one other that has similar features: http://www.portraitprofessional.com/pho … rbrushing/

do you know anyone else that offers similar skin-retouching software/plugin ?

Oct 11 10 05:03 pm Link

Photographer

Artpho Imaging

Posts: 2965

Fairborn, Ohio, US

Photon Mayhem wrote:
I was just trying to find similar software/plugins that offer "automatic" skin retouch, but so far I found only one other that has similar features: http://www.portraitprofessional.com/pho … rbrushing/

do you know anyone else that offers similar skin-retouching software/plugin ?

Watched several of the video's, it looks interesting. I'd like to know your impression of the software.

Oct 11 10 08:13 pm Link