Expressive Black and White Post-Processing: Part I

By 11/10/2017Uncategorised

Expressive Black and White Post-Processing for Fine Art Photography

Part I: First Pass Approaches Explained

03 November, 2017 | Walk-through, Advanced, Black and White, Fine-Art, Photoshop

To achieve a refined, high-end finish for our black and white photography, we should aim to adapt traditional fine-art darkroom approaches to our digital post-processing methods. This is most efficiently achieved in two distinct stages. Let’s go through them both in more detail.

Screenshot of before and after black & white post-processing by M. Seth Jones, completed in Adobe Photoshop. Unretouched image: Johnston, Frances Benjamin, photographer. Carver's Old Mill, Gordonsville vic., Albemarle County, Virginia. 1935. Image. Retrieved from the Library of Congress.

The image on the left is the raw, unprocessed file. The image on the right is the complete, finished file. The final file contained 28 separate layers, combining both global and localised adjustments. As with all of my higher-end post-processing work, this image was completed in two distinct passes. In the First Pass of editing, I restrict my modifications to global adjustments, made to discrete regions of the image. In the Second Pass of editing, I use localised adjustments to hyper-local elements of the image.

In this process walkthrough, I’ll cover the First Pass approach of post-processing. In ‣ Part II of this series, I cover the Second Pass approaches in detail, so be sure to read that once you’re done here.

In expressive post-processing, there is no photographic truth

Let’s have a look at the before and after transition in motion first, to compare the difference between the two states.

As you can see, the finished image is significantly darker overall, however pay attention to the way the light quarter tones and darker highlights shift in relation to the dark quarter tones and lighter shadows. There’s some interesting compression of tonal balance happening here. What’s even more interesting is that this final image is not correct in any sort of universal way. This is simply the finish I wanted to pursue. You might see it and think it’s too dark, or too flat in the exterior ambience, or maybe it’s overly sharpened. The reality is, all of those lines of thought are correct.

Now let’s have a look at the individual stages of the complete, finished image, step-by-step. This will give you a chance to see how each stage of editing modifies a single element in the image, while establishing a foundation for each successive adjustment, along with the overall aesthetic direction of the image. This is essentially a direct line into my personal train of thought throughout the process of working on the image, as each stage is presented in the order in which I applied it.

At every step of the post-processing workflow, we should always seek to take the considerations and motivation behind each discrete adjustment into account. We should always attempt to ensure the final image is a delicate balance of precisely varied single modifications, each playing an essential role in contributing to and achieving the overall finish. The challenge with expressive post-processing is knowing what the finish should actually be.

Anyone who tries to tell you that the craft of making a fine file (or print) is in someway connected to an objective photographic truth is lying. This is controlled expressive manipulation, plain and simple. The hand of the photographic post-processor is intended to be present as both a depictive and detective artifact in the finished work, however the goal at the front of our modifications should always be entirely transparent; that is, we should always seek to use only the values in the capture to modify the values in the capture.

To paraphrase Ansel Adams then (because I’m sure he’d just love that), finish quality is essentially a matter of sensitivity to values, which varies greatly between individuals. Rather than attempting to achieve a predefined standard, we should strive to ensure that the values of the final image suit the pictorial and optical qualities of the capture itself, and contribute to our intended visual effect. To better understand our visual intentions, we should always remain cognisant of the wholly subjective nature of our own instinctive visualisation sensibilities.

Separate the image into its main pictorial elements

Screenshot of an unretouched linear raw file with and without pre-processing pictorial separation. The coloured regions define the discrete sections of the image that the post-processor will modify independently of one another.

Before I begin marking the raw file up, I’ll establish the baseline pictorial structure for local adjustments. This is simply separating the file, conceptually, into multiple discrete pictorial elements that I’ll alter independently of each other. It’s pretty common that as I progress through the post-processing, I’ll refine these to either split an element into multiple segments, or merge one into another. For now though, I can see four elements I’d like to treat separately as a starting point:

  1. Subject
  2. Grain Sacks
  3. Interior distance/background plane(s)
  4. Barn exterior

I’ll begin to literally separate these elements not long after I begin editing, but for now, they will simply serve as a framework for my markup.

Always mark up the linear file to guide your vision

Screenshot of an unretouched linear raw file with and without post-processing markup applied. The markup defines the aesthetic direction the post-processor will apply to the image.

I’ll always start from a linear baseline file for both comparisons sake as I progress through the post-processing, and to guide my (entirely subjective) markup decisions. While marking up black and white photographs, we account for both luminance and surface considerations. The overall balance of the linear baseline is front-heavy; that is, there’s a muddy cluster of light quarter tone details sitting nearest the viewer, with not a lot of clarity between them, followed by a jarring wall of heavier shadow and dark quarter tone details, that feel like they take up less than a quarter of the composition.

What I’d like to do is create a little more harmony between the interior and exterior of the barn, enabling the subject to stand on their own, luma wise. I want to do this while retaining the density heavy interior distance, but have a more gradual transition from farthest interior plane to exterior environmental light. I want the image to invite the viewer not only inside the barn, but around the frame of the composition, to more slowly reveal optical details and create a more weighted sense of three dimensional depth.

The approach for turning the markup into a finished file isn’t all that different from taking a contact print to a fine print in the darkroom; I’ll find a baseline density value to act as a luminance anchor for the entire image, then locally adjust discrete pictorial sections of the image to establish a guide baseline file.

The importance of anchor values for expressive visualisation

Generally, for my initial adjustment I’m looking to set a baseline anchor value, which is similar in principle to a base exposure in the darkroom, however I’m not thinking in terms of dMax here. Digitally it’s a different approach to simply setting the black or white points. An anchor value, for me, is a broader, more global aesthetic quality that the finished file might aim to achieve.

An anchor value is a detective quality; that is, it’s an overall characteristic of the photograph, but not necessarily a trait that is photographed. When we look at a finished photograph of a human subject posing by a window, with a full expressive range of values, we implicitly notice the qualities of the environmental light. Even when we lack the insight, vocabulary or inclination to understand it more thoroughly, it continues to shape the manner in which we read and interpret the depictive elements of the fine print.

In this particular example, I’d like the image to read heavy in density. Not simply dark, but for the values left of 127 to feature more prominently in the finished image, regardless of output intentions, and to sit with clarity in the overall finish, rather than muddied together. This is an entirely subjective decision, divorced completely from any notion of a universal standard that one should adopt absolutely. It’s simply what I like to look at, what I’d like to look as I work through this file, and what I think would work best for this particular photograph. It’s also what I think will best guide me throughout the multiple passes of adjustments to achieve that particular finish, and will help work with me to reach that goal, rather than against me.

Establishing a global baseline anchor value

The first step I take is establishing the foundation for the darkest detail preserving values in the file. At the start of a file, I’ll adopt the position of considering the file in terms of seven distinct luminance targets: blacks, shadows, dark quarter tones, mid tones, light quarter tones, highlights and whites. In the case of a density heavy finish, I’ll try to globally establish the blacks, in addition to all of the shadows and around 30% of the dark quarter tones, with a luminosity ramp graduated roll off starting around 50 or so.

To ensure I don’t throw my upper mid and light quarter interpretation baseline off, I’ll also add a couple of subtle, targeted luma lifts around 140 and 190. Even though I’m focusing on those heavier density values to the relative left of the histogram, if I allow linear global adjustments to cut these lighter values as well, it can shift how I read the values and alter the foundation for further modification. Kind of like looking at a bright yellow screen for 10 minutes before attempting to colour correct a photograph.

Further to this, the modifications here are pretty significant: the global, near linear cut to a large chunk of left of 127 values is showing up without the upper mid/early light quarter values as seen here with them all zeroed out. It takes the surface establishing qualities of the outer left and right frames of the barn and completely washes it out. Again, there’s no universal truth to this process; I don’t need to retain those values (and they’re relatively easy to re-establish) but a) I’d just like to, personally, and b) I need to always keep in mind how one modification sets a foundation for successive modifications. There are literally thousands of possible finished variations of this file, and the difference in both pictorial and aesthetic qualities conveyed between 10 different values can be immense.

Reducing the dynamic range of discrete elements for a better mix

Turning my attention to the left and right outer frames of the barn, I’ve got a slight difference in global luminance between the two. This makes sense; the light source is about 55/45 in favour of camera-right, and the front length edge of the barn skews from the viewer along the same plane. Removing any semblance of optical truth from the equation, I’m focused here on creating a smaller dynamic range between the luminosity values of the left and right outer barn edges. There’s a natural contrast increase in higher frequency edge variation on the wooden surfaces camera-right, plus two or three naturally darker planks, which initially feels a little like throwing off the transparency of the current file. In much the same way a rough, blocked in mask in the early passes of a studio-to-outdoor composite might look, this subtle shift in overall luma values between left and right exterior surfaces draws attention to itself which, in turn, highlights the heavy handed baseline adjustments.

Interestingly, it also adds the first of many initially undetected luminance compositional elements; namely, the structural angle of the light as it cuts diagonally through the frame, shifting from exterior to interior guideline almost perfectly from lower camera-right door frame to upper camera-left door frame. The scattered luminance variation present in the camera-right side planks helps to break up the linear luma gradient inside the barn that progressively rolls off the main subject plane-by-plane to the pure black rear of the interior. There’s a relatively full range of light values on the currently visible right side of the main subject plane – chair, clothing, shirt, hat, cuffs, jacket – which almost perfectly mirrors the variance the outer left barn displays with it’s matching pictorial elements, the lower contrast and significantly less luma-variable fertiliser sacks.

Always favour luminance based lighting modifications

Next I apply a luma-relative lift to the 120-220 values on the subject. Initially this gives me the distinct impression of a poorly composited modification; it’s a well-worn, aesthetically dated approach and looks as if we threw a heavy negative vignette around the edge of the canvas and applied a casually feathered inverted oval mask over the subject. Post-production should be a gradual, step-by-step process. As I’m treating each pictorial element in the file discretely, I have to look past the rough edges of the current merged composite and overall lack of transparency in my edits. I’m simply trying to establish a luma baseline for each independent element within the frame.

There’s not much in the way of complex technique going on at this stage. I’ve applied a relatively simple cut to the baseline shadows, to a) align the darkest surfaces on the subject to the same black levels as it’s surrounding areas, and b) create a stronger dynamic range on the subject itself, to begin to increase the pictorial contrast on the subject’s clothing, amplifying the optical capture. It’s a wide-band shadow and dark quarter tone cut that runs into a broad, targeted boost around 190, with a gradual rolloff either side and a slight parallel cut from 127 down with a luma-relative ramp at both ends. It also includes the first plane behind the subject, as there is a natural gradient transition from the luma values present on the subject to the luma values immediately behind the subject, so the added modification rolls off nicely.

Don’t modify the values on a single pictorial element only

The grain sacks need a little recovery here, for a couple of reasons. Firstly, I’d like to shift the lighter values here to be more in line with the equivalent, neighbouring values on the subject. Secondly, I also want to settle them into the intensity of light we expect to see hitting the front edge of the doorway, in turn making the roughly composited look of the subject against it’s surroundings look a little less cut-and-paste. This in turn helps to align the sacks with the causal qualities of the foreground, creating pictorial definition between the exterior surrounding doorframe. This has been achieved with two second order, narrow bandwidth curve responses at the far left and far right of the histogram.

Don’t accept the raw values as the final expressive truth

We don’t really have a true background here, but we do have a few planes of interior distance to work with. The furthest visible plane from the viewer needs to be recovered now, and established within the black, shadow and dark quarter tone framework I’ve already established.

This is done in a few separate passes, with discrete modifications made to:

  1. the far distance, which is the plane in the image farthest from the viewer with visible detail before the interior drops to pure black;
  2. the upper half of the middle distance interior divider, which is an extension of the original middle background that was boosted with the subject, which needs to be rolled off into a more pleasing transition before it hits pure black; and finally
  3. the entire middle background section, modified as a whole, to create a stepped luminance rolloff from the front of the barn entrance to the rear.

While not entirely essential, it creates a less jarring visual transition from subject focus to pure black distance, ensuring the subject sits more accurately within the currently applied lighting modifications. This helps to ensure the current adjustments convey to the viewer in a more photographically transparent manner.

In the process of making these edits, I also realised I had some crushed blacks in the distance that were sitting around 12-15 or so, creating a less than desirable clash between the established pure blacks of the furthest interior plane and the solid area of (intended) non-detail.

Create added weight, depth and visual rhythm within the frame

In all of the interior background adjustments, I was simply looking to adjust the surface qualities of all pictorial elements until I found replica qualities; that is, depictive details that mirrored the exterior surfaces, to establish a sense of aesthetic harmony between the discrete edits. The interior surfaces were a fairly inconsistent mix of both high and low contrast structural elements, so I wanted to extend the horizontal rhythm of the exterior wooden planks to within the barn itself, while still giving the interior surfaces their own unique identity. Achieving this was simply a case of establishing some heavier blacks, while retaining the gradual luma rolloff from exterior to interior.

This also helps set a depictive rhythm for transitioning into the farthest background plane, with it vertically lower horizontal dividing lines. There is a wonderful pictorial gradation from:

  1. exterior barn planks, horizontal dividing marks, to;
  2. interior middle distance background planks, horizontal dividing marks, ending with;
  3. furthest distance background plane, interior ladder steps.

These horizontal dividing marks continue plane by plane from upper frame right to lower middle frame left, parallel with the compositional rhythm established by the pose of the subject. Even the transition from middle interior background plane to furthest interior background plane repeats the pictorial metre of the subjects crossed leg in a concurrent manner.

Always refine your initial pictorial elements as you progress

The final modification I made in the first pass is the chair, which ended up being one of my favourite depictive elements in the entire image. By this stage however, I’d lost most of it to the shadow it was surrounded by. With no target modification applied, all I’m looking at is the initial base darks adjustment I made to establish the overall luma baseline anchor.

There’s some beautiful detail in the chair, and the slightly imperfect right angles of the chair frame not only help to establish how the subject is grounded in the overall composition, but create a point of interest in the shadow area underneath the subject, breaking up the heavy blacks that, at this stage, make it almost seem that the subject is floating. The entire chair frame is lifted in the light quarter tones and highlights with a fairly wide bandwidth, and a first order mid range contrast boost adds a small amount of structural variance to the frame, rolling off around 160 or so. Finally, the upper horizontal leg is boosted with the same adjustment again and balanced in around 40%, independently of the initial adjustments.

This becomes my initial base composite, establishing the foundation for more refined, targeted local adjustments in the next stage of edits. It’s absolutely too dark here for output. The density-heavy finish does, in it’s own subjective way, enhance the global aesthetic qualities of the composition. It’s not unsuitable or working against the depictive qualities of the scene, but it does tell me I need to push some more refined depictive and detective qualities of the photograph to the front of the finish before it’s ready for export.

Now rest your eyes, you need them fresh for the second pass

Now that the first pass of processing is complete, I need to turn my attention to a more intricate value based approach to refine my initial adjustments before the file is ready for output.

In the video above, you can compare the before and after transitions of the final, complete file on the left, and the current in progress merged composite on the right. While I’ve managed to transform the image significantly, creating a pictorial depth and aesthetic mood that wasn’t as present in the linear raw file, you can see that I’ve skewed a little too dark in the image on the right. And by ‘a little’, I mean ‘a lot’. So how does the Second Pass of editing help me achieve this more compressed, luma-accurate finish?

In ‣ the next part of this series, I detail my approach to achieving these edits in the most photographically transparent manner, and discuss more insights into why I need to implement them.

Image Attribution

Johnston, Frances Benjamin, photographer. Carver’s Old Mill, Gordonsville vic., Albemarle County, Virginia. 1935. Image. Retrieved from the Library of Congress, https://www.loc.gov/item/csas200904177/.