Cinque Terre: Techniques


Dan Margulis
 

In the Niagara image there was no big secret as to what we were after. It was, however, technically difficult to get there and beyond the skills of some of us.

This one is *not* technically difficult but some of us had difficulty figuring out what it is that we’re trying to accomplish. I’d say there are two or three good images here and then six or seven that are slightly off, any of which could reasonably have been chosen for the par version. Part of the reason for some of the shortcomings is that there are so many different ways to go. Some of them don’t have correct answers, particularly,

*Should we take steps to enhance the sky and/or sea? (Note the progression in our case studies: in Veiled Bride the background was so boring that most of us tried to suppress it; in Niagara Spray it was so critical that we had to try to enhance it; and here it’s important enough that we certainly don’t want to hurt it, but it’s unclear how hard we should try to make it better.

*Should we add some sort of yellow-orange cast, either because we want to make the scene sunnier, or to emphasize the age of the buildings? ##502, 514, 517 and 521 thought so.

Both of the above come down to personal preference, so we can’t say what’s right or what’s wrong. Certain other areas are clearer.

*This goes back to a post by Jorge Parra. This is an antique village. In real life the colors are quite dull. We don’t remember them that way; they have to be made somewhat more intense. How much is up for discussion. Holding my nose, I guess I could accept anything between the weakness of #501 and the gaudy #510.

Any more color than that, however, turns the scene into Disneyland and should be rejected out of hand. In that category, I count the blinding ##506, 507, 513, 517, and 519. These are hereby set aside, to be discussed in a second post, because there’s an easy solution.

The distinguished delegation from the Netherlands, doubtless being even more appalled by these candy colors than I am, announced that it is more conservative. And so it is—if we speak of color only. And of course if they choose conservative color then there is no arguing, no right or wrong.

But there *is* a right or wrong in another area, and if I may speak like a Dutch uncle not just to them but to the owners of ##503, 514, 518, 519, 520, and 522, it is wrong to have the image seem washed out.

At this stage in our lives we assume that almost all entrants find a highlight somewhere in the center of the sky, and a shadow somewhere in an infinite number of choices. It’s hard to get a satisfactory version if these items are ignored, but just getting them right is not enough. Everyone should want depth, three-dimensionality, in the village. The way to do this is to assign a larger range to it. The problem with that strategy is we have to find some other range to sacrifice and this is likely to hurt something important.

The lightest significant part of the village is the neutral roofs closest to us. The literally darkest parts are various windows, but they have no detail and are not important. Instead, we’d choose one of the darker buildings, or possibly the lightest area of the solar panel or whatever it is at bottom left center of the image.

Everybody gets about the same value for the light roofing, which is the second lightest significant thing in the image after the sky. There is much more difference in the darker buildings.

What is the impact, what is the price, of darkening that area? The benefit is more depth in the village, the water, and the sky. The cost is that definition is lost in the hillside at right. To me, this is an easy choice.

To show the impact, I’ve planted sampler points in the two key areas, For example, in the par version I read the light roofs as 89L and the light part of the dark panel at 43L, a range of 46L. I now repeat the measurement with all other entrants, excluding ##505, 512. and 513 (obviously plugged shadows) and also #506 and #511 (measurements invalidated by haloing). Here are the results:


#501: 41
#502: 47
#503: 39
#504: 52
#507: 45
#508: 43
#509: 55
#510: 40
#514: 39
#515: 56
#516: 47
#517: 41
#518: 34
#519: 38
#520: 29
#521: 41
#522: 37
#523 par: 46

If you run through these pictures you’ll note how these numbers closely correspond to how much definition is perceived in the village. And to show that a lower number is not conservatism but dubious technique, if you have a number lower than 40, or perhaps even lower than 45,

*Open up #515 or #502, or even #501 or #521. These are all pretty much plays on contrast in the village without extraneous stuff like much darker water.

*On a duplicate layer, apply the one you chose to your image, in Darker or Darker Color mode to protect anything you may have done to the water.

*Change layer mode to Luminosity at, say, 50% opacity.

I suggest this will make the scene look fuller and better.

Dan Margulis



Jim Sanderson
 

Thanks Dan for the comments.  I used 502 to blend into mine.  Looks much better.

Jim Sanderson


-----Original Message-----
From: Dan Margulis via groups.io <dmargulis@...>
To: colortheory@groups.io
Sent: Tue, Jun 16, 2020 3:19 am
Subject: [colortheory] Cinque Terre: Techniques

In the Niagara image there was no big secret as to what we were after. It was, however, technically difficult to get there and beyond the skills of some of us.

This one is *not* technically difficult but some of us had difficulty figuring out what it is that we’re trying to accomplish. I’d say there are two or three good images here and then six or seven that are slightly off, any of which could reasonably have been chosen for the par version. Part of the reason for some of the shortcomings is that there are so many different ways to go. Some of them don’t have correct answers, particularly,

*Should we take steps to enhance the sky and/or sea? (Note the progression in our case studies: in Veiled Bride the background was so boring that most of us tried to suppress it; in Niagara Spray it was so critical that we had to try to enhance it; and here it’s important enough that we certainly don’t want to hurt it, but it’s unclear how hard we should try to make it better.

*Should we add some sort of yellow-orange cast, either because we want to make the scene sunnier, or to emphasize the age of the buildings? ##502, 514, 517 and 521 thought so.

Both of the above come down to personal preference, so we can’t say what’s right or what’s wrong. Certain other areas are clearer.

*This goes back to a post by Jorge Parra. This is an antique village. In real life the colors are quite dull. We don’t remember them that way; they have to be made somewhat more intense. How much is up for discussion. Holding my nose, I guess I could accept anything between the weakness of #501 and the gaudy #510.

Any more color than that, however, turns the scene into Disneyland and should be rejected out of hand. In that category, I count the blinding ##506, 507, 513, 517, and 519. These are hereby set aside, to be discussed in a second post, because there’s an easy solution.

The distinguished delegation from the Netherlands, doubtless being even more appalled by these candy colors than I am, announced that it is more conservative. And so it is—if we speak of color only. And of course if they choose conservative color then there is no arguing, no right or wrong.

But there *is* a right or wrong in another area, and if I may speak like a Dutch uncle not just to them but to the owners of ##503, 514, 518, 519, 520, and 522, it is wrong to have the image seem washed out.

At this stage in our lives we assume that almost all entrants find a highlight somewhere in the center of the sky, and a shadow somewhere in an infinite number of choices. It’s hard to get a satisfactory version if these items are ignored, but just getting them right is not enough. Everyone should want depth, three-dimensionality, in the village. The way to do this is to assign a larger range to it. The problem with that strategy is we have to find some other range to sacrifice and this is likely to hurt something important.

The lightest significant part of the village is the neutral roofs closest to us. The literally darkest parts are various windows, but they have no detail and are not important. Instead, we’d choose one of the darker buildings, or possibly the lightest area of the solar panel or whatever it is at bottom left center of the image.

Everybody gets about the same value for the light roofing, which is the second lightest significant thing in the image after the sky. There is much more difference in the darker buildings.

What is the impact, what is the price, of darkening that area? The benefit is more depth in the village, the water, and the sky. The cost is that definition is lost in the hillside at right. To me, this is an easy choice.

To show the impact, I’ve planted sampler points in the two key areas, For example, in the par version I read the light roofs as 89L and the light part of the dark panel at 43L, a range of 46L. I now repeat the measurement with all other entrants, excluding ##505, 512. and 513 (obviously plugged shadows) and also #506 and #511 (measurements invalidated by haloing). Here are the results:


#501: 41
#502: 47
#503: 39
#504: 52
#507: 45
#508: 43
#509: 55
#510: 40
#514: 39
#515: 56
#516: 47
#517: 41
#518: 34
#519: 38
#520: 29
#521: 41
#522: 37
#523 par: 46

If you run through these pictures you’ll note how these numbers closely correspond to how much definition is perceived in the village. And to show that a lower number is not conservatism but dubious technique, if you have a number lower than 40, or perhaps even lower than 45,

*Open up #515 or #502, or even #501 or #521. These are all pretty much plays on contrast in the village without extraneous stuff like much darker water.

*On a duplicate layer, apply the one you chose to your image, in Darker or Darker Color mode to protect anything you may have done to the water.

*Change layer mode to Luminosity at, say, 50% opacity.

I suggest this will make the scene look fuller and better.

Dan Margulis



Robert Wheeler
 

Good additional exercise. To my #520 duplicate layer I applied #502 in color darken mode and put the layer into luminosity mode, tweaking opacity to about 50%. The additional contrast does help the depth of the image, and the change is not as extreme as I had imagined. Gradually accumulating experience like this is very helpful.

I used Google Earth to search on the name of the region and then navigated in for a closer look at several of the villages along the shore. Dropping down to street view shows very narrow streets, with building colors reasonably vibrant in spite of any bleaching effects of Mediterranean sunshine.  However, I have no idea how Google street view approaches color management.


Alec Dann
 

Dan,

You mention that colors are often remembered as being more saturated than they were at the time they were experienced.  I first encountered that observation in Margaret Livingstone's book, "Vision and the Art: The Biology of Seeing," a book that is full of useful information for photographers.  Livingstone doesn't reference the source of her observation.  Are you aware of any studies of color memory that explore the saturation of remembered colors?

I'd be interested in learning more about it.

Alec


Alec Dann
 

In the PAR version, the hill on the left looks darker than it should be.  Your eye would adapt to that level of illumination so it should be at least as bright as the opposite hill.  This gets into the treacherous territory of what your visual system does (5 degree area of focus changing every second) versus a sensor, but that just makes for an interesting discussion.

Alec


Dan Margulis
 

Roberto, who knows that this is a winter shot, admits in his post that he deliberately made his #510 more colorful than the actual scene, trying to emulate summer warmth.

The author of #511, in his private note to me, says he is very familiar with the area and knows that the buildings appear somewhat washed out in real life; he intentionally produced “eye candy” instead.

The author of #507, who has never been to Cinque Terre, went looking for help on how to portray it, and was disappointed. He writes: ““My ‘memory colors’ sky & sea from [my home] probably depart quite a big from how things look in Italy. Worse yet, when I tried to cheat and find some reference images on the web, I got assaulted with truly awful-looking unreal super-saturated hyped-up solor, super bad HDR images—kind of caricatures of bad travel photos.”

In my initial posting of this case study I pointed out what we all now know, this picture is not going to sell unless we make it more colorful than the original scene. Unfortunately it’s hard to know where to stop. In my previous post I called out ##506, 507, 513, 517, and 519 for going way overboard and producing Disneyland colors. And, as the comment above indicates, we are not the only people who have this problem.

Our group made heavy use of MMM-related actions, and rightly so. Most images present us with one or more items that are distinctly more colorful than the rest. Here, we’re confronted with a bunch of pastels, all of similar darkness and saturation, and many of similar colors. MMM creates some of the luminosity and hue variation so urgently needed.

I don’t believe that anybody but myself used H-K, which isn’t often helpful but which really stands out in this kind of shot. I invite you to try it as below and remind you that the PPW panel carries its own PDF documentation. But the brief summary is that it creates two correction layers, adjustable by opacity, mask or whatever. Both work with modified saturation masks, the more neutral the color, the lighter the mask.

*The H-K Effect layer darkens these more neutral areas, with a supplementary routine that prevents shadow plugging. Here, that’s good: when two sides of a building are visible the darker one is always more neutral, and gets darker yet, adding contrast.

*The Color Only layer neutralizes them even more, leaving more saturation difference between the brighter and duller colors. Since everything in this Cinque Terre shot is somewhat neutral, the whole image will become too gray, but that’s no problem for us, we fix it in LAB. And when we do, we can make the brightest colors just as bright as they were in ##506, 507, 513, 517, and 519, but the duller colors won’t come along for the ride and the overall impression is less colorful, but with attractive color accents.

Here are three ways to test it, easiest to hardest.

1) Grab one or more of the above fireballs, or maybe even #510, and apply H-K to it. This is a horrible misuse of the action; it’s designed to be used early in the process, not at the end. In spite of that, it clearly improves things.

2) #515 is the version I did in 2017. As I was trying to hold the correction time to three minutes, I didn’t go in for any of the fancy stuff with water and sky. #501 is my most serious competition from the MIT retouching team; its color is believable, if uninteresting. I rated this competition a decisive win for PPW. But why?

Since neither of us was doing any fancy selection/retouching, the basic answer is H-K. My version has some strong colors but they are accents and do not overwhelm the viewer. The other guy could have pushed saturation a little but any more than that would have sent us to Disneyland. Try it for yourself.

Starting with #501, run H-K. On top of the H-K stack, add a Hue/Saturation adjustment layer and add saturation to taste. Then, toggle off the H-K action and admire the mess.

3) For those who had the problem of too much color, you might want to do another version, incorporating H-K fairly early, before finalizing the color in LAB.

Dan Margulis


Paco
 

Hello to all!

 

Mine is 517.

 

My approach was to give the image a softness which would reflect the very diffused quality of the light in such an overcast sky. I went for pastel colors and not much detail on the buildings which I find very unappealing emphasizing their weathered aged look. This decision is a creative one and has nothing to do with portraying the buildings in a realistic manner. The image is supposed to be a pretty one intended for tourists.

 

The par version is exactly what I did not want. I screen captured both and jumping between them I perceive the par version to be too harsh and contrasty. As far as the colors, in both, the tonalities are close; the difference being that I chose to make mine more pastel but still having “weight.”

 

I don’t agree at all with Dan’s view that the colors in the buildings of my image are “blinding.” They are pastels and on the warm yellowish side because they ARE on the warm side of the spectrum. This warmness I took advantage of in order to make them stand out from the greens and blues.

 

The image is basically composed of sea/sky, hills and town. The town, in my opinion, being the subject of the photo.

 

The sea and sky are right  smack in the middle of the photo and compete with the buildings and hills for attention. I decided to give the sea and sky more detail but just enough texture to make them less in your face and thus take away their prominence. The hills I made less contrasty/dark and more colorful so as to introduce contrast with the colors in the town. The buildings have to be colorful but not garish as in the par version. The enhanced contrast in the par version also takes away from the softness of the light.

 

So what I am seeing is a par version which might be technically correct but less easy on the eyes than mine.

 

This brings me to make the point that technique need not supersede creative interpretation. I take inspiration in the Fauvist/Impressionist movement which prized feeling over technicality and reality.

 

Kudos to all who submitted their versions. Even if they are deemed a disaster all efforts teach us something. And then, Dan’s teachings give us all these amazing tools which, like a formula 1 car can be so powerful that part of understanding them is learning to use them wisely and carefully.

 

All the best!

 

www.pacomarquez.com


ROBIN MARK D'ROZARIO
 

Dear Dan,

Thanks for this.
My submission 319 is part of the Disneyland group( the lightest, brightest and with apparently very very offensive colour!)
However, I fully intended it to be this way as I felt my initial efforts followed the original too closely and produced a dreary image of an overcast but colourful town. I didn't think this was suitable to promote tourism to the sunny Riviera. 
With the proviso that I was aiming for light pastels I tried using the Colour and Luminosity layers of MMM to achieve colour and luminosity differences. However, I found that most of the time the Luminosity layer added a stronger effect than I wanted for this image.
I've run H-K on my version with the colour layer turned off and it does add a pleasing more gentle contrast to the image. I assume that the different reactions from both these Luminosity layers  is because one is based on saturation and the other on the L channel.
At what point would you normally run H-K, before or after contrast moves,Bigger Hammer etc?

Best regards,
Robin Mark D'Rozario


Dan Margulis
 



On Jun 17, 2020, at 9:44 AM, Paco <paco@...> wrote:

Mine is 517.

 

My approach was to give the image a softness which would reflect the very diffused quality of the light in such an overcast sky. I went for pastel colors and not much detail on the buildings which I find very unappealing emphasizing their weathered aged look. This decision is a creative one and has nothing to do with portraying the buildings in a realistic manner. The image is supposed to be a pretty one intended for tourists.

 

The par version is exactly what I did not want. I screen captured both and jumping between them I perceive the par version to be too harsh and contrasty. As far as the colors, in both, the tonalities are close; the difference being that I chose to make mine more pastel but still having “weight.”

 

I don’t agree at all with Dan’s view that the colors in the buildings of my image are “blinding.” They are pastels and on the warm yellowish side because they ARE on the warm side of the spectrum. This warmness I took advantage of in order to make them stand out from the greens and blues.


Paco,

My apologies! I must have written down the wrong file number. I do not believe that your version is “blinding” at all. I said that I found Roberto’s #510 too colorful for my taste yet still acceptable, and his version has much more intense color than yours.  Your choice of hue for the village is very nice, a prudent middle point between neutrality and some of the extremely yellow versions done by others.

My slight criticisms would be that the village seems somewhat washed out and the hillside at right calls too much attention to itself, but these have nothing to do with your color choices.

Again, my apologies.

Dan


Dan Margulis
 



On Jun 16, 2020, at 1:17 PM, Alec Dann via groups.io <alec.dann@...> wrote:

You mention that colors are often remembered as being more saturated than they were at the time they were experienced.  I first encountered that observation in Margaret Livingstone's book, "Vision and the Art: The Biology of Seeing," a book that is full of useful information for photographers.  Livingstone doesn't reference the source of her observation.  Are you aware of any studies of color memory that explore the saturation of remembered colors?

I'd be interested in learning more about it.

Alec

Jorge Parra mentioned such a study by Fuji, and I replied, in

Dan


Paco
 

No need to apologize Maestro!


Gerald Bakker
 

On Tue, Jun 16, 2020 at 12:19 PM, Dan Margulis wrote:
The distinguished delegation from the Netherlands, doubtless being even more appalled by these candy colors than I am, announced that it is more conservative. And so it is—if we speak of color only. And of course if they choose conservative color then there is no arguing, no right or wrong.
 
But there *is* a right or wrong in another area, and if I may speak like a Dutch uncle not just to them but to the owners of ##503, 514, 518, 519, 520, and 522, it is wrong to have the image seem washed out.
Well, let's call it "Dutch contrast" then. (I know of a few combinations where the word Dutch has a cynical meaning, but had never heard of a "Dutch uncle".)
Anyway, you are right that the village in my version gets a much better look when merged with a more contrasty version. I had focused too much on color, forgetting that good contrast is at least equally important. Lesson learned.

What is the impact, what is the price, of darkening that area? The benefit is more depth in the village, the water, and the sky. The cost is that definition is lost in the hillside at right. To me, this is an easy choice.
Interesting that you describe this as a global change. Why should we consider losing definition in the hillside as a price to pay? It's very easy to filter out the greens and browns in a layer mask, maybe a 10-second action. I just did that, using a rather large and very soft brush, and it's absolutely invisible. No need to be precise at all.
--
Gerald Bakker
http://geraldbakker.nl


Thomas Hurd,MD
 


Dan,

The eye opener for me was when you said to try the H-K on a finished version 501, and then place a hue saturation layer on top. I did this with several entrants. Seeing the variation helped me understand the action better. And, it helped me understand this assignment better.

I originally had used the H-K move last week but found it too darkening for me to overcome later in the workflow. However, putting wailing aside, I tried the corrections over again yesterday and today.

Yesterday, I tried to match the par version, from scratch as a (hypothetical) test. I used every tool I could find, including masks, and side by side info panels.
 
Also thanks for redirecting me toward the work at hand. I rethought my results and how I got there. Trying to match the par version from scratch forced me see how far my corrections were off (or not so much). Then I could concentrate specifically toward how to achieve a specific global or local color contrast.

Today I tried my more traditional PPW workflow but including the H-K action. It worked fine, of course. I used it after color and contrast correcting and applying the bigger hammer with an RGB overlay layer and lighter color blends on the darkening layer. Then after H-K with both layers active, I used MMMCB (inverted a mask on the color boost layer) and Sharpening at 50%. The Bigger Hammer was in the past difficult for me to get good results. However,I rewatched the videos you recorded about it for the book, and once I understood the panel’s options, it opened the tool up for many more of my images the last 4 days.

I appreciate everyone’s willingness to share their workflows!

Tom


On Jun 17, 2020, at 10:16 AM, ROBIN MARK D'ROZARIO <rdrozario@...> wrote:

Dear Dan,

Thanks for this.
My submission 319 is part of the Disneyland group( the lightest, brightest and with apparently very very offensive colour!)
However, I fully intended it to be this way as I felt my initial efforts followed the original too closely and produced a dreary image of an overcast but colourful town. I didn't think this was suitable to promote tourism to the sunny Riviera. 
With the proviso that I was aiming for light pastels I tried using the Colour and Luminosity layers of MMM to achieve colour and luminosity differences. However, I found that most of the time the Luminosity layer added a stronger effect than I wanted for this image.
I've run H-K on my version with the colour layer turned off and it does add a pleasing more gentle contrast to the image. I assume that the different reactions from both these Luminosity layers  is because one is based on saturation and the other on the L channel.
At what point would you normally run H-K, before or after contrast moves,Bigger Hammer etc?

Best regards,
Robin Mark D'Rozario



Dan Margulis
 



On Jun 17, 2020, at 11:22 AM, Gerald Bakker <gc.bakker@...> wrote:

(I know of a few combinations where the word Dutch has a cynical meaning, but had never heard of a "Dutch uncle".) 

Per the American Heritage Dictionary of Idioms:

A stern, candid critic or adviser, as in When I got in trouble with the teacher again, the principal talked to me like a Dutch uncle. This expression, often put as talk to one like a Dutch uncle, presumably alludes to the sternness and sobriety attributed to the Dutch. [Early 1800s]

You are right that the other idiomatic references to your nation tend to be cynical, but not this one.

Dan


Jan Hof
 

On Wed, Jun 17, 2020 at 05:03 AM, Dan Margulis wrote:
Then, toggle off the H-K action and admire the mess
With regard to color, the use of H-K action was a real surprise to me. I hardly use it in my workflow. I tried the second option and it works surprisingly well with this image: it separates colors and makes it possible to get a much colorful image without arriving in Disneyland :-).

Definitely something to keep in mind for this kind of images.

------

Jan Hof


Jan Hof
 

As a Dutch person, I had a lot of uncles but they weren't Dutch uncles....

I didn't know the expression either, but when searching on the internet, I found that there is a Wikipedia page, dedicated to expressions with Dutch in it. And it were a lot more than I expected!!

-----

Jan Hof


Dan Margulis
 



On Jun 17, 2020, at 10:16 AM, ROBIN MARK D'ROZARIO <rdrozario@...> wrote:

I've run H-K on my version with the colour layer turned off and it does add a pleasing more gentle contrast to the image. I assume that the different reactions from both these Luminosity layers  is because one is based on saturation and the other on the L channel.

No, the both derive their info from saturation, although one *acts* on luminosity only and the other on color only.

At what point would you normally run H-K, before or after contrast moves, Bigger Hammer etc?

Right after any channel blending but before any Hammer actions.

Dan


Doug Schafer
 

I have struggled over time to learn how much is too much color saturation or contrast.
Not sure each time I do an image if I hit the mark on both.

I can easily tell those that are flat or pale vs. bold in contrast or color saturation, especially when compared to my effort "after the fact".
But that seems too late, except for learning, and learning seems to be a slow process.

I have found a few .atn "tests" for oversat on a grey layer...but not sure if any good; as results vary with different tests run. If color shows then probably it is over-saturated.
I have never found any good measure (except by eyeball experience), of "correct" or best contrast.

Dan, are there any checks we can make (like using histogram for checking black and white points), for checking contrast and saturation?

Doug Schafer


Dan Margulis
 



On Jun 17, 2020, at 11:22 AM, Gerald Bakker <gc.bakker@...> wrote:


What is the impact, what is the price, of darkening that area? The benefit is more depth in the village, the water, and the sky. The cost is that definition is lost in the hillside at right. To me, this is an easy choice.
Interesting that you describe this as a global change. Why should we consider losing definition in the hillside as a price to pay? It's very easy to filter out the greens and browns in a layer mask, maybe a 10-second action. I just did that, using a rather large and very soft brush, and it's absolutely invisible. No need to be precise at all. 

Maybe “a price to pay” is the wrong phrase. Better to say, the hillside will lose definition as a result of this correction *if you do nothing to protect it.*

The real question is, why should we take the ten seconds to correct it? This picture is not about the hillside, it’s about the village, and if the hillside loses definition so much the better, say I. Back in the Veiled Bride exercise a lot of us deliberately caused the background to close up so that it would become less interesting, and I believe this hillside should be treated the same way.

Dan



Dan Margulis
 



On Jun 17, 2020, at 4:58 PM, k_d@... wrote:

I can easily tell those that are flat or pale vs. bold in contrast or color saturation, especially when compared to my effort "after the fact".
But that seems too late, except for learning, and learning seems to be a slow process.

I have found a few .atn "tests" for oversat on a grey layer...but not sure if any good; as results vary with different tests run. If color shows then probably it is over-saturated.
I have never found any good measure (except by eyeball experience), of "correct" or best contrast.

Dan, are there any checks we can make (like using histogram for checking black and white points), for checking contrast and saturation?

Since a histogram doesn’t know what the picture is about, it can’t offer an opinion on how much contrast or saturation is appropriate. A photograph of the city of Venice would have a histogram similar to one of the fake scenes of the Venetian Hotel in Las Vegas, but these two scenes would need to be handled differently.

A histogram-related possibility that might actually be useful, although I don’t particularly endorse it:

Suppose you have a version of the village in Cinque Terre, and you wish to know whether you should try to add more pop to it.

1) Add a duplicate layer

2) Make a two-second, sweeping lasso selection of the interior of the village.

3) Image: Adjustments>Equalize

4) In the ensuing dialog, choose Equalize entire image based on selected area

5) Reduce layer opacity, remembering that this is only for investigation and no great precision is needed.

The ancient Equalize command was originally known as Equalize Histogram. That’s what it does: it spreads out the histogram in the selected area, which can be the equivalent of adding contrast to it.

This layer is almost certainly useless and should be discarded, but it may give you a hint that you should be trying harder.

Dan