William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.  There is no "low/high frequency layer" in Photoshop.  This is one of those things that someone picked up from a book somewhere; then wants to use the term to pass themselves off as being "knowledgeable". 

My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

Did you even take the time to read that thread?

William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.  There is no "low/high frequency layer" in Photoshop.  This is one of those things that someone picked up from a book somewhere; then wants to use the term to pass themselves off as being "knowledgeable". 

My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

I'm confused.  I'm not capable of separating image data into high (relative) and low (relative) frequencies, and naming the layers after such?  Because that's what I'm doing, and have never needed a curve to do it (though they obviously get fun when you apply them to those layers - maybe not wet dream fun, but fun just the same).

Edit to add:  Oh, and just so we can all be self-righteous, all sources of information in that thread were duly cited (as well as I consider that to be possible in an internet forum thread), and most certainly didn't come out of some K3lby book.

William Kious wrote:
My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

My guess is that your guess is based on a lack of understanding of what frequency means in terms of image analysis and/or signal processing.

In the case of a 'low frequency layer', it's describing the results of splitting an image into lower and higher frequency layers--the parts of the image with rapid frequency changes (high frequency) vs parts without (low frequency)--or, in layman's terms, broad areas without changes vs parts with fine detail.

It's becoming not uncommon (not yet common, but increasingly so) to use this decomposition process to assist in photographic retouching, just as it has been for forensic and other analytical image processing.

It's by no means necessary--just as it's not necessary to use layers in Photoshop, or the clone tool, or the healing brush, FFT, or any other tool or technique. It simply provides alternatives to other approaches.

William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.

You know, what I constantly find amazing is how some people will mock new concepts before they even look at the concept itself--much less understand it. It's as if by being something they haven't already heard of makes it inherently flawed. Fortunately, some people are less prone to this sort of knee-jerk reaction, or we would still be living in trees and caves.

William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.  There is no "low/high frequency layer" in Photoshop.  This is one of those things that someone picked up from a book somewhere; then wants to use the term to pass themselves off as being "knowledgeable". 

My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.  There is no "low/high frequency layer" in Photoshop.  This is one of those things that someone picked up from a book somewhere; then wants to use the term to pass themselves off as being "knowledgeable". 

My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

http://www.encyclopedia.com/doc/1O13-sp … ilter.html

There are plenty more if you do a search for "spatial frequency" and you can narrow it down by including "separation" or "low frequency" if you want.

Even wikipedia has a decent, though short, article about spatial frequency.

And just so you know, the terms "high frequency" and "low frequency" as they apply to spatial frequencies have been in use since before Photoshop was even a wet dream for Thomas Knoll.

William Kious wrote:
My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

I'm not getting into this coz I dont have enough knowledge (for PS) but THATS FUNNY!!!! Coz sine waves on a oscilloscope is niiicceeeee.........but damped sine waves are NICER!!! God I'm so sad! I like waves........

Sean Baker wrote:
It may come from this thread, as I expect what you're referring to is the lower frequency layer of spatially-separated image data which in sum comprise the whole.

how do you Spatially separate a 2-D image. That makes no sense to me. Frequency-Sampled would be more correct although we're still not dealing with X-Y-Z values, so Digital Sampling sounds a bit more proper terminology

Rebel Photo wrote:
how do you Spatially separate a 2-D image. That makes no sense to me. Frequency-Sampled would be more correct although we're still not dealing with X-Y-Z values, so Digital Sampling sounds a bit more proper terminology

It's a spatial frequency separation technique.  Take a look at the thread and if you still have questions post them there or send a note.

Sean Baker wrote:
It's a spatial frequency separation technique.  Take a look at the thread and if you still have questions post them there or send a note.

isn't it actually Tessellation?

I'm simply debating the term

Rebel Photo wrote:

isn't it actually Tessellation?

I'm simply debating the term

No, I believe tesselation would be more analogous (though still not directly) to something like what surface blur does or some of the new research smoothing operators do.  Nothing is kept distinct by the original implementation of the technique whereas the newer operators attempt to do this by definition.

Sean Baker wrote:

No, I believe tesselation would be more analogous (though still not directly) to something like what surface blur does or some of the new research smoothing operators do.  Nothing is kept distinct by the original implementation of the technique whereas the newer operators attempt to do this by definition.

Hmmm...I've worked in real 3-D for years, I guess I'm just not thinking along the same lines (no pun intended)

Rebel Photo wrote:

Hmmm...I've worked in real 3-D for years, I guess I'm just not thinking along the same lines (no pun intended)

The definition I've gone by of tesselation is that it is the breakup of the larger image into discrete, largely shape-based subsections for purpose of simplifying the rendering / rasterizing process.  Being that I don't work in 3D, am I completely off base here?

The thread referenced deals with separating a 2D image into its component waveforms (or at least as well as we're able with the tools we have) and using that information for various purposes (emphasizing the high frequencies to sharpen, de-emphasizing intermediate frequencies for skin smoothing, etc.).  The term 'spatial frequency' was taken out of writing from Dr. Livingstone at Harvard.

KMA2SQ wrote:
Well, I AM an engineer, but it would probably help if I was an electrical or optical engineer to understand this a little better.  What I've picked up is that whoever it was who dropped that term probably didn't have much of a clue as to what they were saying.
I get that images can be decomposed into a spacial frequency representation, and that maybe with the right understanding, you could predictably manipulate an image in such a domain.  At this stage it sounds a lot like something that I have little hope of mastering.  That is unless taking the convenient interpretation of low and high frequency representation as the breakdown that LAB color gives you, with the color on one layer and the shading on another, but I know that isn't what the scientists are talking about.

Did you read the linked thread?  There's a lot of good information, countless explanations, and a good number of folks waiting and willing to help you in there.

KMA2SQ wrote:
Well, I AM an engineer, but it would probably help if I was an electrical or optical engineer to understand this a little better.  What I've picked up is that whoever it was who dropped that term probably didn't have much of a clue as to what they were saying.
I get that images can be decomposed into a spacial frequency representation, and that maybe with the right understanding, you could predictably manipulate an image in such a domain.  At this stage it sounds a lot like something that I have little hope of mastering.  That is unless taking the convenient interpretation of low and high frequency representation as the breakdown that LAB color gives you, with the color on one layer and the shading on another, but I know that isn't what the scientists are talking about.

Sean Baker wrote:
Did you read the linked thread?  There's a lot of good information, countless explanations, and a good number of folks waiting and willing to help you in there.

Along with examples and downloadable scripts/actions to help get you started.

Sean, is this starting to sound like a sales pitch?

William Kious wrote:
You know, this is one of those things I'm not going to keep my mouth shut about.  There is no "low/high frequency layer" in Photoshop.  This is one of those things that someone picked up from a book somewhere; then wants to use the term to pass themselves off as being "knowledgeable". 

My guess is that the originator of this bullshit term was looking at a tone curve in Photoshop and had an oscilloscope wet dream.

troll??

Sean Baker wrote:

Did you read the linked thread?  There's a lot of good information, countless explanations, and a good number of folks waiting and willing to help you in there.

OK, now I understand where you're coming from.  Yeah, I thought the first post was such a gem, but now there's so much more!  'Great stuff!

Kings Media wrote:
I hope I dont look like a total noob, but that highpass thread just overwhelms me, the first post alone....Well it has more than one technique to linked parts of the thread. Which do I follow?? Do I download the original action or is there an u pdated version? idk.

If you have questions pertaining to the highpass thread, you can post them there as others who keep an eye on that thread may be wondering the same thing. You will get a lot more help with questions about that thread by posting in that thread.

To answer your question, there are updated versions of the action set. I'm also working on a newer version that should work with anyone's preferences or close to it.

Photons 2 Pixels Images wrote:
To answer your question, there are updated versions of the action set. I'm also working on a newer version that should work with anyone's preferences or close to it.

I've also been following that thread and watched all the actions "morph".  I don't mean to disparage anyone's work, because the techniques and the actions are way beyond what I would spend time trying to figure out.  But what started out as a great sharpening technique with a simple process and action has turned into something totally different - retouching.

Using the latest action set I'm left with a multitude of layers - none of which make a lot of sense and none get me a sharpened image.

If nothing else, instructions would be nice.

Prose Photography wrote:
I've also been following that thread and watched all the actions "morph".  I don't mean to disparage anyone's work, because the techniques and the actions are way beyond what I would spend time trying to figure out.  But what started out as a great sharpening technique with a simple process and action has turned into something totally different - retouching.

Using the latest action set I'm left with a multitude of layers - none of which make a lot of sense and none get me a sharpened image.

If nothing else, instructions would be nice.

If your using photon's latest action, there is a sharpening group, simply click it and paint white on the areas you want to sharpen.

To the OP and naysayers:

Been using PS extensively for about 15 years give or take, I'm not going to go on some ego centric tirade but I know my stuff.

What Sean, Photon, grahamsz and what that thread in general has evolved into is nothing short of epic and very constructive.

I don't care if he calls it the "Fluffy Kitten" layer and the "Not so fluffy kitten" layer, what it allows you to do, and additions people have made to the concept is highly effective in a multitude of applications.

I'm a pretty seasoned pro, and I've never thought of frequencies on the image before, or how to control them and edit out rages. Now I have a pretty good understanding of the concepts, thanks to them and I'm very grateful.

Prose Photography wrote:

I've also been following that thread and watched all the actions "morph".  I don't mean to disparage anyone's work, because the techniques and the actions are way beyond what I would spend time trying to figure out.  But what started out as a great sharpening technique with a simple process and action has turned into something totally different - retouching.

Using the latest action set I'm left with a multitude of layers - none of which make a lot of sense and none get me a sharpened image.

If nothing else, instructions would be nice.

I hope this doesn't sound rude as I'm not a rude person, but can you post any questions about that in the Highpass thread? I'll write up a description of the latest action set posted on Aug 12 that includes the RGB/8, RGB/16 and PS7 actions and if you have any other questions, please ask. There may be others that want to know also.