Questions upon questions....

This is the discussion thread for the September 2010 Class.
mikemeister_admin
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Postby mikemeister_admin » Tue Sep 28, 2010 10:48 pm


Art,
I'd like to try something with you if you'll indulge me...Can you give me a bit of time to prepare something for you?  I'd also like you to post a recent image that you want to "fix" and tell me what you think you would do to fix it...All tools on the table not just CM.  If you would just fix it in Photoshop...tell me what tools and techniques you are going to use to fix it.

What I want to get at; is what process you are currently using and how, or when; we can change that process to use Curves.  If we even need to use curves and if we do..then how and why it relates to your description of what you think needs to be done to fix the image.

I'm betting you know lots of Photoshop tricks to get more out of the images...
Greg


I don't have a picture on hand, so I used one of your example pictures for this week.  It's the last picture....the towers.  I did this in 5 seconds with just Photoshop.  It may not be perfect, but I'm satisfied with the results. :)
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Postby mikemeister_admin » Tue Sep 28, 2010 11:04 pm


Art,

Here is my request...
Correct the image attached so that the number 2 disappears.  Use only RGB.  Start by setting 2 hue clocks.  one in the number and 1 on the background.  Make the Number the same color as the background.  I know that you are going to say it makes no sense...but please try...let's keep it simple and see where we get...

Greg


I don't know how to Greg.  I set two hue clocks like you said, then just stared at the picture.  I played around with each curve by pulling the line up and down, but that did nothing.  I have no idea how to do achieve the result you wanted.  Sorry.

ggroess
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Postby ggroess » Wed Sep 29, 2010 12:22 am

That is where the next post comes in...

Art,
Take a look at the attached color chart.  I used red for this but it applies to all the RGB color channels and all images...
On the chart you have 1 color channel from the RGB color space.  Red.  In the middle I have a color gradient and below that hue clocks. 

As you look at the color gradient;  Notice that it lines up with the edge color of the Curvemeister Red channel grid.  That the light end lines up with the light end of the gradient and the dark end lines up with the dark end of the gradient.  This is a more visual road map for everyone to use. 

If you look at the hue clocks and only look at the R value R=Red.  you will see that in RGB (the top row of hue clocks) that the R number changes as you move across the gradient.  On the Far left it is 255 that is all of the red color that is possible in RGB.  If Green and Blue are also 255 as shown you get white. 
Notice that the LAB hue clock below it has a 2 and a -3 along with a L number of 97.  Since Red is a warm color it really should be a positive number and if you look closely the hue clock has a slight cyan tint to it..(I tried to get it to 0). The trouble with the LAB values is that working in that area of the curve (so close to 0 or the center) it is almost impossible to get a single channel to be stable.  This is one of the reasons RGB is a better color space for color correction...

Onward.  The LAB values you need to understand are the L = Lightness and the A channel which covers Red/Green.  The same color produced the two different hue clocks because of the huge amount of math behind the color space. LAB is calculated by totally different math from RGB and thus has a different system of numbering.  In RGB the scale goes from 0 =no red to 255=all red.  In LAB the scale goes from 0 = neutral to 128 All the red possible.

Again onward.  In RGB there is no single color channel that can be neutral.  Neutral means no color cast or essentially Gray.  In RGB each color channel only contains color.  If a pixel has an RGB value  other than 0 or 255 it is contributing to the color.  It is the combination of the three channels that creates the colors.  Every possible color in RGB is made by combining each channel RGB together.  Every Pixel in RGB has 3 numbers to represent it.  If those values are equal in every channel regardless of the value then you have a neutral.  0,0,0 or 255,255,255 or even 141,141,141.  It matters not, what the number is if you are making a neutral. 

If you are making a color it matters completely.

In LAB you have the same image but a totally different way of thinking about the color.  In LAB we separate the lightness(L) from the color (A and B).  Changes in the L channel are equal to changing all 3 RGB channels together so long as they are the same value. You are in effect working on only the gray scale in the L channel.  With A and B each channel has a set of color values Let's look only at the A channel. 

The A channel has color values ranging from -128 to +128 with 0 in the center of the grid.  In LAB the + numbers are the warmer colors.  Red and yellow are warm therefore they are positive numbers on the scale.  Blue and Green are considered Cool Colors so they are negative numbers. 

Each pixel in LAB is represented by again 3 numbers but a different set of three.  If you look at the far lower lfet hue clock and only look at the first set of numbers you will see that the values are (L97,a2,b0)  97 represents 97 out of 100 where 100 is white. The "a' value is +2 this means it is warm or red in the a channel.  and the B value is 0 or neutral.  So this tells us that the color is very light red. 

So where do I adjust the curves??  The Blue arrows show the approximate areas of the curve where you would find the colors in the hue clocks. The reason I did not point to the exact spot is that in any color sample you have multiple pixels giving you a calculated average for the selected sample point.  there are tools in CM like "mark" that allow you to set the exact points on the curve and make the location easier.

I'll walk you through the blue number exercise in the next posting.  I wanted to try to answer your question about the hue clocks and what they mean with a solid visual and some hue clocks showing you how they relate.

Greg
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Postby mikemeister_admin » Wed Sep 29, 2010 1:14 am

Greg, I have no idea what your post is talking about.  It's all Greek to me.  A color gradient?  What is that?  "Notice that it lines up with the edge color of the Curvemeister Red channel grid."  Huh?  No idea what that means.

Most everything after that is total incomprehensible to me.  Like I said in an earlier post, your explanations are way over my head.  I can't decipher what it is you're saying.  You're talking in another language that is foreign to me.

Hue clocks are just a nuisance to me that blocks the picture I'm working on.  I'd rather delete them and work on the picture.  Their hieroglyphics don't mean anything to me, so I turn them off.

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Postby ggroess » Wed Sep 29, 2010 2:42 am


Greg, I have no idea what your post is talking about.  It's all Greek to me.  A color gradient?  What is that?  "Notice that it lines up with the edge color of the Curvemeister Red channel grid."  Huh?  No idea what that means.


Art the color gradient is the bar of color in the middle of the frame that goes from white on the left to dark red on the right.


Most everything after that is total incomprehensible to me.  Like I said in an earlier post, your explanations are way over my head.  I can't decipher what it is you're saying.  You're talking in another language that is foreign to me.


Learning the language of color correction can be a project in itself.  I have no other simplified terms I can use that convey the same meaning...Anyone else care to take a swing at it??


Hue clocks are just a nuisance to me that blocks the picture I'm working on.  I'd rather delete them and work on the picture.  Their hieroglyphics don't mean anything to me, so I turn them off.


Art I understand that you do not like the hue clocks..they are a primary tool used in color correction to help you. 
How will you know if the color is right if you do not examine it??  Correction by eye is only as good as your monitor...monitors use color profiles and they can drift out of "correctness" over time....I use hue clocks to show students that there is a problem in the image and that they can correct it. 

Being frustrated is a very difficult place to be.  I'm not sure how I can help you when you post an image that most would say needs some work and yet you are certain you are satisfied.  The whole point of CM is to make this faster and easier..I can see that we are doing neither for you. 

Please let me know what it is I can do to help; I certainly am willing to go further.

Greg

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Postby mikemeister_admin » Wed Sep 29, 2010 4:11 am



Art the color gradient is the bar of color in the middle of the frame that goes from white on the left to dark red on the right.


Then why not say that instead of the color gradient?  Or better yet, say it like, "color gradient (the bar of color in the middle of the frame)."  That would explain it in simpler terms.

Art I understand that you do not like the hue clocks..they are a primary tool used in color correction to help you. 
How will you know if the color is right if you do not examine it??  Correction by eye is only as good as your monitor...monitors use color profiles and they can drift out of "correctness" over time....I use hue clocks to show students that there is a problem in the image and that they can correct it.


I understand that, but if it looks okay to me, then that's all I'm interested in.  I don't care if some hue clock says it's out of whack, if it looks okay, then it's okay.  If it's a picture for someone else, I can guarantee you that they will also think it's okay.  It isn't necessary to tweak a picture to the Nth degree to get a decent picture.  As a matter of fact, several of the examples you posted were perfect the way they were.  The picture of the wreath, the picture of the three people walking across the street, and the picture of the flower were great the way they were.  If I had taken those pictures, I'd be perfectly happy with them and I wouldn't make any adjustments to them.  To adjust them to get a tiny bit more color from them doesn't make sense to me.  They are fine as is.

Look at the picture of the three people walking across the street.  Without using hue clocks, can you see anything wrong with it?  I can't.  After you've done whatever the hue clocks tell you to do, compare it side by side....the original and the adjusted picture.  Is there really that much of a difference?  I don't think there is, and that small amount of adjustment won't make any difference, and I doubt that you could see that the original picture needed that small amount of adjustment when you looked at it without a hue clock.

Look at it this way.....if you used hue clocks to edit a picture, and the end result wasn't to your liking, would you leave it that way?  I wouldn't, I would adjust the picture until it LOOKED good to me.  Isn't that what the end result should be.....if it looks good to you?

By the same token, I'll edit a picture to get it to look like I want it to look.  That might mean that I want it to have a slight color cast to it.  That's what I'm shooting for.  The idea is to end up with a picture that has the look that I want, not a look that some hue clock says is correct.  Getting a bunch of hue clocks to align in some way may not give me what I want in the picture, so why bother with them?  It all comes down to what you want the picture to look like.

Being frustrated is a very difficult place to be.  I'm not sure how I can help you when you post an image that most would say needs some work and yet you are certain you are satisfied.  The whole point of CM is to make this faster and easier..I can see that we are doing neither for you.


That was why I decided to quit the class.  All I am doing is frustrating you and me, and I don't want to create extra work for you in an attempt to help me.  I'll never get it.

Please let me know what it is I can do to help; I certainly am willing to go further.

Greg


There isn't anything that you can do.  We are on different levels, and I don't see any way to bridge that gap.

The thing is, I feel like those who understand CM and use it extensively, feel like CM is the only thing you'll ever need to edit pictures.  I don't agree with that.  CM is just another tool that can be used with other tools to edit pictures.  If I was proficient with CM, I'd never use it as a first tool when I edited a picture.  I'd use it as a last tool if I couldn't get the results I wanted.  To me, CM is a last resort and nothing more....just like the curves are in Photoshop.

I am curious though....in the picture of the towers that I made 5 seconds of adjustments to (in the first post on this page), what does CM tell you is wrong with it?  I'm perfectly happy with it, and I'd never want to tweak it any further.  I went for darker shadows, but I could have reduced them by lowering the amount of contrast I used.  What does CM say?

ggroess
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Postby ggroess » Wed Sep 29, 2010 1:25 pm

I can see by looking at the image; no CM involved... that the sidewalk is overexposed and that the shadows on the spires are still blue.  The skin tones in the people are OK but I'm betting the background person is too red.

I can go into CM to verify but I'm reasonably sure that I'm in the ball park.

I do not teach that CM is the be all and end all of image correction.  I always talk about the fact that it is a tool to be used in image correction and added to your other tools and techniques as needed.  There are many things that CM cannot do.  Mostly, CM makes tasks associated with color and tonality in Photoshop vastly easier.  This would only apply if you feel the image needs adjustment. 

Part of the process everyone takes in their own way is identifying a problem and then trying to fix it. Otherwise, why even have Photoshop.  Having more tools to fix problems is generally seen as a good thing.  Having a tool that can do multiple things at once or faster and more accurately is a very good thing.  Learning to use that tool is always a choice.


Greg

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Postby mikemeister_admin » Wed Sep 29, 2010 1:50 pm




I do not teach that CM is the be all and end all of image correction.  I always talk about the fact that it is a tool to be used in image correction and added to your other tools and techniques as needed.  There are many things that CM cannot do.  Mostly, CM makes tasks associated with color and tonality in Photoshop vastly easier.  This would only apply if you feel the image needs adjustment. 

Part of the process everyone takes in their own way is identifying a problem and then trying to fix it. Otherwise, why even have Photoshop.  Having more tools to fix problems is generally seen as a good thing.  Having a tool that can do multiple things at once or faster and more accurately is a very good thing.  Learning to use that tool is always a choice.


Greg


I agree Greg, that's why I wanted to learn CM....to have another tool in my arsenal of editing tools.  I just wish CM wasn't so difficult for me to understand.

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Postby mikemeister_admin » Wed Sep 29, 2010 4:07 pm

I wanted to add that when I place hue clocks on a picture, since I don't understand what they are indicating, then all they are doing is blocking my view of the picture underneath.  That is why I turn them off.  If I can't understand them, then they are just in my way.

I really would like to know what to adjust to accomplish what you wanted in the problem you posted for me.....the dark blue square with the light blue "2" in the middle.  How would you accomplish that?

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Postby sjordan93436 » Wed Sep 29, 2010 4:11 pm

You can click and hold on the hue clock and drag it off the image.


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