How to Create Image Specific Tonal Curves
What I'm going to teach you how to do today in theory is how to create image specific tonal reproduction curves in which you can be image structure specific so you're gonna have total reproduction curves in total reproduction curves rgb is not a color it is a formula to mix color gray is a color it consists of equal values of red green and blue and on this printer this printable print black light black light light black magenta and cy are light magenta light scion and I think yellow are the colors that it uses so it's using color inks a conjunction with the gray ings to produce one of these images that you're using colors to produce the images that it's equal values of gray that create the image do you see where I'm going with this that the conception of what I hear frequently from people that teach photography I've made it a point to watch every movie I can get read every book that I can read is oh color doesn't matter it's contrast it's all about lightness and darkness contrast or cu...
e that doesn't matter it's just saturation or my personal favorite is well if you're trying to find a photograph to photograph in black and white make sure that when you're out in the world it has a lot of contrast secret to photographing incredible black and white is to photograph an incredible color image and from that you can then create the black and white image of your dreams were in the first time where if we can imagine it we can create it that's the power of digital photography so let's the reason why you want to do it last has to do with this image right here would you agree that that's out of focus how about now taking that up right? I've sharpen this seven times the reason why I can get away with sharpening it seven times that I put all seven sharpening layers on different layers and I use opacity to blend it because all artifact ing is cumulative and maybe multiplication ve the goal is to negate multiplication artifact ing into minimize cumulation artifact ing what is accumulation artifact in look like if I applied all of the seven sharp innings that I did to an image that's what it would look like that's multiplication artifact ing the reason why you want to leave your black and white conversions to the end has to do with handling a raw file which should be handled with his little touch on it it's possible how many people bake pie crust? Okay well you handle pie crust as little as possible a raw files pie crust leave the heroic things where you have layers and you have a pass it and you have layer masks so that you can negate multiplication artifact ing and only have to deal with accumulation artifact okay let's take a look at the lovely shall in cates this is the red channel this is the green channel this is the blue channels are these all by our definition a chromatic grayscale or grayscale image they have a black they have a white and they have a great scale ramp in between they're all the same image structure but this is different than that and this is different than that but they all three meet our definition what you're looking at is predictability this is the red channel this is the green channel this is the blue channel when you put them together you get color this is what film recorded it recorded a collision between these three frequencies of light red, green and blue and from that they produce whatever the black and white was that you bought you picked portrait's rage h p five plus landscapes or pan atomic x or try x three twenty based on the way in which recorded things so let's take a look at simply removing all of the color does that meet our definition ok do you see where the color got in the way the picture so now this meets my definition but let's look at the channels that's a red channel that's agreed in channel that's the blue channel what do you observe? Nothing happened they're all the same so the problem is that I've lost the relationship between red, green and blue what I have left is luminant ce in rgb so I don't want to do that right? So let me ask you this you've got clouds clouds or basically what great and they pick up the reflection of the ground beneath him and the group ground beneath them is brown and tia brown in your great clouds do you do a multi channel mixer approach our multi plugging approach where you simply do de saturation d saturate the color out of the clouds and just brushing the clouds yes simplest way is always the easiest oh did I not introduce this class welcome to it makes absolutely no sense would you like me to show you that? Okay it's ground hog day whatever like for example the first thing you're taught in photography get it right in the camera right? Yes so that says that you should set your camera to monochrome because you're getting it right in the camera right? I know the reason why you don't want to do that is because cameras take the green channel which is where luminous is in midtown and replicates to the red and the blue. So what happens is you have all the head room of whatever your camera is but with none of the benefit of the collision between red, green and blue so yes you want to get it is right is possible but no you don't want to do that it will all make sense to at least me when I'm done okay so let's take a look at let's create a serious of files here so that we can look at them duplicate this call this l a b one pitch these two things is the one joy of working uh with projectors is that I have no screen acreage left and let's duplicate this again call this lab too and then let's duplicate this again we will call this gs let's start with convert grayscale and so the first thing I'm going to do and I want you to watch this number down here how much is that file number what's that number thirty okay first thing I'm going to do is I'm going to get an image mode grayscale what's that number now what did I just do? I just dumped two thirds of my data that means that those two thirds of data that you could have access that were in there held in the red in the blue and those two channels are gone to you. You've lost the relationship between red, green and blue and as you can see they're different the red was lighter and creamier the green had more mid tones in the blue tended to be darker and deeper ok so let's zoom back so this is our grayscale image will put this over here we'll call this decent we'll call this gs let's, go to lab let's. Convert! Get back here! Let's convert this one to lab so we're gonna go image mode l a b and what you should see is absolutely nothing happened. So let's, take a look at our channels. That is the l channel. Does that meet our definition? Yes, and there is usable information in there. Yes, this is the a champ. Is there anything that you visually configure out? How to use for your chromatic gray scale conversion in that channel? Really? No good. You're shaking your head like do you know this is the beast channel again? So what happens here is that yes, it may contain all the components that will produce a full, visible spectrum color image, but the access to the data eludes you. Now what happens in the first conversion process is called the classic black and white conversion technique because since its log rhythmic, it replicates the way in which film would have recorded it. Okay, so what I'm going to do here is I'm going to throw away my two channels. What number do I have there? So what did I do? Don't two thirds of my data ok, though that's the technique then requires that you go to gray scale, okay, then you go to rgb, what did I get back? I have all of the head room of that file but none of the collision between red, green and blue I do not have access to the channels so all I did was deflate the tire, take all the important stuff out and made the tire bigger but with nothing in it it worked didn't it guess you had to be here for that. All right, so let's, take this and call this l one and that's drag l one over here to our comparison files its clothes out of that we don't need it now after there was some hullabaloo about that just basically being you're just doing illuminates channel the next one was convert to a lab. Okay, nothing happened convert to gray scale ok, discard the information and if we look at this again what number do I have back here? Okay, so once again I've wiped out and then convert the rgb let's call this hell too. All right, so let's, take a look at these let's get out of this. This is l one and that cell to lab conversion one lap conversion to do you see a difference? Okay, this is convert to gray scale and lab one. Do you see a difference? Okay, this is convert to gray scale in lab two do you see a difference? So the second newer version of the classic black and white conversion technique than the classic black on white conversion technique basically does with photo. Shop does in convert to grayscale, except adds a couple of extra steps. So if you have nothing better to do with your time than to just run through photoshopped, this is the technique for you. This is de saturation of the image. The saturation of the image actually renders us closer more usable picture than either one of the lab conversions. The reason why you don't want to consider using the lab color spaces, because you can't predict it. You do not have access to the red, green and blue channels of the file.
High quality black and white images require careful handling – learn the best way to work on yours in Black and White Photography: Learning Grayscale Conversion with Vincent Versace.
When you convert your digital image from color to black and white, you destroy ⅔ of the data in the file. In this class, Vincent will explore the complete conversion process and show you how to protect what remains. You’ll learn how to preserve your image’s contrast, control the individual color channels, manage the hue and saturation layers, and how to print.
Black and White Photography: Learning Grayscale Conversion with Vincent Versace will help you ensure that every black and white image you work on looks its absolute best.
Software Used: Adobe Photoshop CC 2015