The Great Paynter European Photo Adventure- Post One

I just finished a 30-day trek around southern Europe with my best friend (my wife Barbara), and my Lumix G5. This composite shot (one of over 4500 taken during the trip) is of one of the Dresden Museums, just down the plaza from Frauenkirche cathedral. I left my big Nikon at home and traveled with my mirror-less Lumix G5, two lenses, and a MeFoto Roadtrip tripod packaged in a CaseLogic sling. Dresden is an amazing city! Put it on your bucket list.

I put myself on a very strict photo regimen. Since I preach about the necessity of understanding light, I figured I had to put it into action. I decided to shoot by The Deerhunter mandate: one shot, one kill. No bracketing, no retakes, and no peeking. Dangerous? You bet. Scary? Yep. But a very rewarding challenge. I only reviewed the images each evening as I downloaded them to my laptop.

For the most part, the images are unedited. What you see is what the camera captured.

Dresdon Museum PanoThis image started out as three images that were “photomerged…” in Photoshop. Aside from that, they are virgin pixels. Morning sunlight coming across the scene provided the contrast. Low ISO (160), f5.6 aperture and a moderate (1/400) speed provided the stable focus. Spot metering on the glass above the front door delivered the tonal balance. The WB was set to Daylight.

Dresdon Museum Pano BWSince the image contained a full range of tones, the resulting black and white was pretty much a straight conversion with just a little contrast added for drama.

Reading and metering the available light accurately and setting the camera to address those readings almost always delivers results for me. The real discipline is in taking the time to use my brain before I use my camera. Get bright about light and the dividends will pay off big time.

I also suggest that you take the opportunity to learn more about the basics of light and color from my video series entitled the “Gotta Know Videos: Part One- Light and Color.” http://gottaknowvideos.com

Until next time, this is Herb Paynter

hpaynter@imageprep.net

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Shedding Light on Black and White Part 3: The Digital Conversion


A comparison between the way film-based cameras and digital cameras capture spectral information and transpose that information into black and white images.

Photography is all about Light. The more we understand about the way light behaves, the better we will understand how to capture it, edit  it, and render it in both display and printed form. 

Sorry for the delay in posting this final segment, I just returned from a month-long trek through southern Europe capturing about a zillion images from rich, cultural cities.

Original sRGB Color Camera Capture

Original sRGB Color Camera Capture

This color image of Frauenkirche Cathedral was captured in Dresden Germany. In this session we’ll look into how to interpret your color pictures into rich black and white images.

Each color is converted to a range of gray tones. The trick is to analyze each image for its color content and the relative importance of that color in the grayscale interpretation. 

As with most other issues in photo reproduction, restraint is the key. Considering the interpretive freedom that digital color conversion affords, digital black and white images can actually provide superior tonal transitions to dedicated grayscale film emulsion captures. 

Color vs Monochrome ColorChecker Captures

Color vs Monochrome ColorChecker Captures

First, realize that not all colors are created equal. By this I mean that solid yellow should always produce a lighter shade of gray than red or blue. Probably the best way to understand these tonal values is to shoot an x-rite ColorChecker passport chart using your camera’s Daylight white balance setting (obviously under daylight conditions).

Custom Value Assignments vs Default Grayscale Values

Default Color>Grayscale Value Table

When this RGB file is then converted to Grayscale (from the Image/Mode menu in Photoshop), the relative gray values of the primary and secondary colors can be observed. As each solid color value is revealed, keep these general “solid” values in mind as you build your Custom conversion palette. 

Photoshop provides a powerful color-to-black-and-white conversion tool that allows you to produce a custom table for your individual camera sensor (Image/Adjustments/Black & White…). The default settings for this tool shouldn’t be trusted for “fit” anymore than a one-size-fits-all dress or suit. Use a Monochrome capture of your X-rite colorchecker to visually balance the mix of color channel values to actual grayscale values. 

But even this custom setup shouldn’t necessarily be your ultimate grayscale conversion process. Over time and trial and error, you can develop your personal preference settings.

Custom Color>Grayscale Value Table

Custom Color>Grayscale Value Table

This chart image can be used to fine-tune your grayscale values. Just as Kodak, Ilford, Agfa, and other black and white films provided a color/tone bias, you too can establish your own “Signature” black and white conversion look. Every camera manufacturer’s image sensor records these colors uniquely. With a little experimentation, you can develop a very rich and powerful conversion table to interpret your own camera’s image sensor algorithm.

frauenkirche-dresden-Gray1

Saturation Values Removed

Default Grayscale Conversion Table Results

If you choose to convert your color image to Grayscale (Image/Mode/Grayscale), or simply remove all Saturation values (Image/Adjustments/Hue/Saturation…), the resulting default gray equivalent values will not accurately translate into the proper grayscale values. Never again settle for a lifeless, one-size-fits-all black and white conversion. Monochromatic images are incredible powerful visual statements. Remember, black and white images fuel the imagination in a way that color images simply cannot. Make your black and whites demand the attention of your audience and thus deliver the full impact of your personal interpretation.

That’s the way I sees it. Take some time to experiment with these conversion tools. Shoot some images of diverse color themes and develop your own “signature” conversion table. This is very powerful stuff. Once again, the more you learn about light, the better your photography will turn out. Get bright about light and the dividends will pay off big time.

If you learn a little something from this blog, I seriously suggest that you take the opportunity to learn more about the basics of light and color from my online video series entitled the “Gotta Know Videos: Part One- Light and Color.” http://gottaknowvideos.com

Until next time, this is Herb Paynter

hpaynter@imageprep.net

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Shedding Light on Black and White Part 2


A comparison between the way film-based cameras and digital cameras capture spectral information and transpose that information into black and white images.

Photography is all about Light. The more we understand about the way light behaves, the better we will understand how to capture it, edit  it, and render it in both display and printed form. In this session we’ll look into the light-capturing capabilities of light sensors of two types: CCD and CMOS. I won’t get into the technical differences between the two technologies because it is not germane to this discussion.
What these two systems do have in common is the challenge of recording and interpreting spectral data (the color properties of light) and rendering that information in monochromatic form. While they both see the same light, they record it quite differently. All serious photographers love black and white photography. And all serious photographers recognize the difference between film and digital black and white images. What is not immediately obvious is why there is a difference. I’ll try to shed a bit more light on this issue in this second session in the series.

Film cameras make use of the light-response attributes of silver-halide, and various black and white films are composed of slightly differing formulations of silver and bromoiodide atoms as well as other coatings that record nuances of colors that affect the black and white interpretation of color subjects.
Digital cameras work on a more sophisticated system that involves electrical current. Photo cells actually count photons (the atomic level of light measurement), and use electrical current to amplify the levels (based on the ISO settings).
But here’s where the personality of monochromatic digital captures literally falls flat. When a digital image is captured in monochrome form, the camera discards all RGB information and only records luminous data. While this sounds reasonable for a black and white result, it negates the nuances of spectrally-weighted transformation. Each manufacturer determines how each color in light is parsed as a monochromatic value.
You are literally at the mercy of the engineers writing the algorithms. A process that can be quite mathematical and romantically sterile; all information is recorded in a very flat and mechanical manner. While some very interesting and useful translations are offered by come camera manufacturers, you are still locked into someone else’s interpretation.
When digital images are captured in full RGB color and then transposed into black and white during the  image editing process, you, the photographer get to creatively transpose those spectral colors into gray tones that can more richly interpret colors to tones.
If you are editing in Adobe Photoshop, open the Black and White… menu item from the Image/Adjustments menu. Within this very powerful interpreter, each color can be tuned to a specific gray range, giving you to the total control over how each color is transposed into the monochromatic mode.
The Preset menu offers a number of springboard settings that can be modified to your own liking. The little gear symbol to the right of the Preset menu allows you to save and recall any number of color/mono transpositions. This puts you in control of the conversion process and gives you the power to shape your own black and white images.
That’s the way I sees it. Take some time to experiment with these tools. Shoot some images of diverse color themes and develop your own “signature” conversion style. Very powerful stuff.
Once again, the more you learn about the behavior of light, the better your photography will turn out. Get bright about light and the dividends will pay off big time.
I also suggest that you take the opportunity to learn more about the basics of light and color from my video series entitled the “Gotta Know Videos: Part One- Light and Color.” http://gottaknowvideos.com
Until next time, this is Herb Paynter

hpaynter@imageprep.net

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Shedding Light on Black and White


A comparison between the way film-based cameras and digital cameras capture spectral information and transpose that information into black and white images.
 
Photography is all about Light. The more we understand about the way light behaves, the better we will understand how to capture it, edit it, and render it in both display and printed form.
 
If you shoot with a digital camera and love black and white photography, this series will give you some insider information that should help you understand why digital black and white images don’t have the same “feel” as film-based black and white prints. And I’ll present some suggestions about how to bridge the gap and regain the feel.
 
There are three issues that I’d like to address in this mini-series that will shed some light on the whole black and white issue. The first session will examine how film emulsion and silver halide grains capture and interpret the spectral qualities of light. The second session will look at how digital camera sensors deal with that same spectral information. The third session will present some insights and settings you can employ in both camera capture and post editing that can help you get that film feel back in your black and white photography.
 
Session One: The Silver Connection
First, a little background (and to some folks, a review) about the element of silver and the part it plays in black and white photography. This amazing art form is based on the light-sensitive nature of silver halide. The primary element in the light capture process in photography is the silver halide crystal. 
 
The photographic term “silver halide” refers to the cultured crystals that are formed when silver and bromoiodide atoms are joined and “cultured” on a molecular level. These silver halide crystals are then spread evenly within a gelatin layer and coated (in total darkness) on to a plastic film base. 
 
Black and white (or monochrome) films are produced and marketed by several film manufacturers. Each of these films is engineered to produce a unique visual characteristic. Photographers all have their own preferred “signature” look that is produced by one of these different film brands. These films produce specific results to satisfy the discerning eye of the photographer. Different lots of films also display unique characteristics causing serious photographers to buy a quantity of films from the same lot, storing them in very controlled coolers until they can be used. This produces great consistency in the work of discerning photographers.
 
Depending on how fine the grain is (how small the crystals are), the higher the count of these photo-sensitive light receptors will be in the film window of the camera. Note that smaller (or finer) silver halide grains are less sensitive to light than larger grains. 
 
This is why Kodak’s Tri-X film has a higher ASA rating than Plus-X, and a much higher rating than Panatomic-X film. The larger the grain size, the more sensitive it is to light, and thus the “faster” the film. Larger, more light-sensitive film grain produces much higher levels of contrast. Thus Kodak Tri-X produces images from lower levels of light and appears “sharper” because of the more pronounced definition properties of the silver halide grains.
 
Each of these silver halide grains reacts molecularly to the light hitting it. When exposed to light, each crystal forms a small, stable “latent image.” This latent is invisible to the eye because it has not yet been chemically affected by a development solution. This latent image remains “exposed” as long as the film is kept in total darkness.
 
FILM DEVELOPMENT
When it time to develop the exposed images on the film, the film is removed from the film canister (in total darkness), and wound carefully onto a stainless steel reel; a process that takes significant practice to accomplish without crimping (and thus permanently damaging) the film. This reel is then placed inside a light-tight stainless steel tank. 
 
Development of the latent images on the film takes place when the film comes in contact with an alkaline development solution. There a number of specific development solutions that affect the latent images, each with its own characteristics. Serious photographers carefully choose these development solutions for specific results. 
 
The silver grains darken during the carefully-timed and gently-agitated contact with the developer. Each grain darkens in accordance to its individual exposure to light. This development solution chemically chars the exposed silver grains. Grains that have been subjected to greater light turn darker than grains that have been exposed to lesser light. 
 
The different development solutions produce different internal contrast levels. The timing of the development is critical and lighting conditions during the exposure process can be compensated by “pushing” or overdeveloping the films.
When the development cycle is complete, the spent development solution is drained from the canister and an acid based solution called “stop bath” is poured in. This stop bath solution arrests the development process.
 
The canister is again drained and a hypo-clearing agent (or fixer) is poured into the canister which removes the unexposed silver particles from the emulsion layer and clears away any residual light-blocking properties. 
 
The canister can be safely exposed to normal room light and film is then thoroughly rinsed in flowing water to remove the fixing solution. The film is then submerged in a whetting agent solution to remove any calcium deposits from the water, squeegeed of excess fluid, and is hung in a drying cabinet under very low heat until dry. Until the film’s emulsion is totally dry, it is particularly vulnerable to scratching. Great care is taken to preserve the integrity of the developed image all the way through the development process.
 
So what is the cause of the visual romance with black and white photography? Sensitivity to light, or photographic speed, is one of the most important attributes of the emulsion. Here’s something you might not know…light sensitivity is typically enhanced during manufacture by a heat treatment in the presence of tiny amounts of sulfur and gold compounds (chemical sensitization). Organic dyes, usually cyanine dyes, are then applied to the crystal surface to extend the basic UV and blue sensitivity to other colors in the visible spectrum (spectral sensitization). Different film brands contain emulsions that have been dyed to respond selectively to blue, green, and red light, thus giving b/w photography a visual personality. Simply desaturating digital color images cannot possibly deliver this same tonal character. Converting color images to full-bodied monochromatic images requires a bit of understanding about the behavior and personality of light. A topic near and dear Tom my heart, as you probably realize by now.
 
I’ll get into this issue more in the third session.
 
Factoid: A single ounce of silver can produce enough silver halides to take 5000 photographs.
 
When you are finished, you have a negative image of the original scene. It is a negative in the sense that it is darkest (has the highest density of opaque silver atoms) in the area that received the most light exposure. In places that received no light, the negative has no silver atoms and is clear. In order to make it a positive image that looks normal to the human eye, it must be printed onto another light-sensitive material (usually photographic paper), which reverses the negative image into a positive one. Actually, you could say that the whole film- based photographic experience is a very negative one! (Sorry about that, it was just too easy to pass up.)

Anyway, that’s the way I sees it. 

Join me next time when we look into the way digital cameras deal with black and white images. In the mean time, please take five (actually more like six) minutes to watch a shameless plug about my new video series at http://gottaknowvideos.com/keyfactor.html This is stuff you just gotta know in order to shoot like a pro.

See you next time. Herb

hpaynter@imageprep.net

 

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Dreamers, Mechanics, Propeller heads, and Pundits

Pardon my absence for the two weeks or so, I’ve been doin’ some personal rearranging. This started by engaging in some personal reflection. Always revealing, but somewhat dangerous. Please don’t get offended at this silliness. It just lets me grasp the historical players.

When I was in the litho industry shooting photos and mechanicals/pasteups into pre-press negatives, assembling film, burning plates, and running printing presses I learned quickly the difference between the printing industry and the art community.

Those of us who followed the strict disciplines of the engraving and printing trades dealt with the harsh realities of the physical world. Those who designed logos, dealt with color swatches, and produced art lived by concepts and ideas, but had no earthly idea what was required to turn those fluffy design concepts into printed reality.

For easy reference I labeled the two symbiotic camps with simple descriptors: the dreamers and the mechanics. The dreamers created new and impossible out-of-the-box projects to purposely torture we mechanics.  No amount of explaining the physical limits of the trade seemed to mellow their imagination though, God bless them. They kept life interesting.

Propeller Heads

When the desktop revolution erupted in the mid-eighties a whole new breed of un-humans appeared who had no concept of, or respect for, either the mechanics or the dreamers. These geeky propeller-heads were totally bent on changing all the rules of both camps. All the sudden the dreamers and the mechanics found something in common: they didn’t want to have anything to do with the propeller heads.

These geeky weirdos developed boxes called computers that were based on a whole new expression system. One designed around mathematics. Math had little to do with printing and absolutely nothing to do with design. It was a whole new weird way of life.

The litho group didn’t like them because their silly software was based on a grid system that totally violated the principles of halftone production and their math-based resolution clashed with known screen rulings and angles; 133lpi screens were now calculated at 124.624dpi to accommodate the new film generators called imagesetters. Attempts by the graphic arts community to adapt to this new system created violent problems on press. Moires abounded and type placed on screen tints always had light leaks. Early color separations were based on slide-rule formulas that didn’t account for some of printing’s simple laws of physics- like the fact that paper stretches on press and that equal parts of cyan magenta and yellow don’t produce neutral gray; they actually produce a muddy brown. Professional trade printers (the mechanics) started refusing to accept work produced by the desktop yearlings. The projects they submitted sometimes cost more money to accommodate and correct than the printing job was worth.

The design community were just a dismayed at the choke-hold restrictions of grid-based designing. The free fluid flow of design suddenly had to be forced into geometric pixel arrays. The dreamers didn’t have any idea of what a pixel or an array even was let alone how to draw a smooth curve with tiny jagged square blocks. For a while the geeks were satisfied to print dot-matrix flyers and newsletters. Neither the design community nor the printing industry took the desktop crowd seriously because the “work” they produced was too amateur to consider a threat. But it was an uneasy peace. The winds of war were blowing.

This new geek nation was on a mission to change the world and that included the graphic arts. The obvious next step was to replace the old-school design community and dinosaur printing industry with design geeks. And so it was.

As momentum for the movement picked up and the technology improved, the design geeks started churning out computer-looking printed projects. As more wannabe designers joined the ranks, an entire culture of look-alike publishing projects flowed from laser printers by the ream. Sensing the financial opportunity on the horizon, publications sprung up supporting and promoting these new designers and publishers.

Enter the Pundits

Every movement has its media pundits and this new desktop movement was no exception. Writers and pundits filled the magazines with fresh new ideas about desktop publishing. Regular trade shows on both coasts promoted this phenom rage. As the ranks swelled in the desktop movement, the pundits became the authorities on all things publishing. The articles in the publications were written by the new designers and service bureau workers encouraging more folks to join the publishing revolution.

It took a while for the three camps to hold hands, and a lot of traditional professionals got swept away in the process. But now the circle is pretty-much redrawn as the desktop folks actually started learning good design and the printing industry (those who survived the carnage of the revolution) redefined itself and licked its wounds.

I remember this process well because I played a part in all three camps, and I survived (I think). Life doesn’t necessarily get easier as time goes on, but it does present rewards to those who remain mentally flexible enough to keep reinventing themselves.

Here’s my latest mutation. I invite you to scoot over to http://gottaknowvideos.com/keyfactor.html and take a look at my newest incarnation. It kinda sums up what I’ve learned over the years and want to pass along to the new breed of photographer/publisher.

And that’s the way eye sees it.

If you enjoyed this little rant, pass it along. See you next time.

Herb

http://imageprep.net

If you have an iPad and want to learn more about how your eye buys into the camera’s insidious lies, check this out:

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

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The Brain’s Visual Cortex Corrects Color Casts. Naturally.

The setting in the image capture and editing processes known as White Balance is a curious one indeed. PrintThe human light perception system is so complex, and so intuitive,  that we don’t totally understand how it even works. All human color correction happens so automatically that we sometimes don’t appreciate how worry-free it really is.

As photographers this natural phenomenon becomes more apparent when we deal with the limitations of our cameras to capture and sort out the variety of lighting conditions that occur constantly. Our cameras cannot deal with nature’s lighting changes subjectively, and intuitively like our minds can. This is because camera image processors are machines, and they can only record light objectively. And the white balance controls in both our cameras and our editing software are built purely upon broad assumptions. Therein lies the problem. We assume that our cameras can see light the same intuitive fashion that our eyes do. But that’s a bad assumption.

Your eyes adapt to color temperature changes constantly. To prove this just put on sunglasses that have a slight color tint. While this tint is noticeable for a moment, in just a few seconds the color processor in your visual cortex will recalibrate the scene and completely eliminate the color cast. Any object that your mind recognizes as typically white will appear white even if the color of the light reflecting from it has a color cast.

This is because your eyes and your brain enjoy what we call Memory Colors. Memory Colors are colors that you have seen so often that they are registered in your brain in some form of human reference system. Even if the lighting on an object is less than optimal, your memory colors automatically remove the color cast in your mind.

When the camera sees a color cast it records that color cast quite objectively. Golden hour photographs exhibit a warm cast and as long as our camera’s white balance is set to Daylight, that warm color cast will seem natural. But at the same time, Daylight WB photographs shot in overcast situations will exhibit a slight blue cast that will appear cool and unnatural. To record colors that appear natural, we must set the camera’s WB to Cloudy, which tunes out the bluish cast. If images are captured in the shadow under overcast lighting, the appearance will be even more blue unless we set the WB to Shade. Now that ain’t natural!

Thank you Lord for the gifts of Memory Colors and true Auto White Balance. Remember, you gotta be smart because your camera is capable, but it really isn’t smart! Coming soon: The GottaKnow Video Series. The online video series that will make you bright about light and color savvy. Get Smart. Your camera is depending on it.

That’s the way eye sees it. Feel free to leave a comment and keep the conversation going. If you saw this post listed on a LI group page, add a comment to the listing in that group! Thanks for joining me. If you like this blog, let me know and tell your friends.

See you next time, Herb

hpaynter@imageprep.net

http://imageprep.net

PS. if you have an iPad and are interested in learning about more about the fundamentals of digital photography, I suggest that you take a look at my Accurate Color iBook in the iTunes Store

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

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Image Tonality and the Histogram- Part Six: The Phoenix Scenario

PhoenixIn Greek mythology the Pheonix is a long-lived bird that is cyclically regenerated or reborn from apparent oblivion. In this sense, any digital image capture that is apparently “dead” by all appearance can have life breathed into it by powerful image editing software.

Original Image Histogram

Original Image Histogram

Such is the case with this image captured during an overcast day in Kailua Hawaii. Absolutely no detail can be seen in this JPEG image; all appears hopeless. A reject, right?

Not so fast, quickdraw! We’re here to raise the dead, remember? While nothing can replace the correct exposure, don’t throw in the towel on an image that looks too dark until you’ve tried this magic collection of tone tools.

Kailua Ranch Before Whether the image is captured in jpeg, tiff, or raw format, it can be opened in either of Adobe’s raw interpreter packages, Adobe Camera Raw or Adobe Photoshop Lightroom. Within either of these packages, both chrominance and luminance controls are provided that allow the user to rearrange tones and shape images extensively.

Lightroom Controls

Camera Raw ControlsTo open a tiff or jpeg file in Camera Raw, you must first locate the file in Adobe Bridge, right click on the file and choose “Open in Camera Raw…” You can open these files in Lightroom either internally or by dragging the file onto the LR icon in the dock.

The image pictured above was seriously underexposed and appeared to be hoplessly dark. But when the image was opened in both CR and LR software packages, and the same adjustments were made, identical results were achieved.

Note: the histogram in the CR panel (left) show the results of the Basic dialog adjustments while the histogram in the LR panel (right) shows the result of Basic and Tone Curve adjustments.

Notice that both software packages offer virtually identical tools to shape and reconstruct the image.

Kailua Ranch AfterYep, this is the same JPEG image pictured above after the adjustments to all three tone range points and all three internal contrast ranges. Keep in mind that this was a very overcast day, and I intended to keep it that way! One of the biggest mistakes made in image adjustments is to assume that all images look best when the highlights and middle tones are automatically brightened up. That’s a rookie mistake. You’re no rookie.

Your challenge in image editing is to make the image portray the emotion of the scene the way your eyes saw it. Mood is a wonderful expression that shouldn’t be sacrificed to an Auto-anything button! Save the image but don’t loose the mood in the process. Hrrumph!

I go into seriously more detail on how this was done and the interplay between the tools that affect the six tone regions and points in the Digital Image book, but you get the idea.

This series has been a small excerpt from my soon to be released book titled The Digital Image: From Capture to Presentation and Everywhere In-between. If you find this series helpful, you’ll love the book.

That’s the way eye sees it. Feel free to leave a comment and keep the conversation going. If you saw this post listed on a LI group page, add a comment to the listing in that group! Thanks for joining me. If you like this blog, let me know and tell your friends.

This is the last entry of the spooky series called Image Tonality and the Histogram. I hope you’ve learned a little something extra about the mystogram. I highly recommend that you join the followers of this blog to learn more about imaging. Sign in now as a follower (top right of this page). Don’t forget, good followers usually make great leaders.

See you next time, Herb

hpaynter@imageprep.net

http://imageprep.net

PS. if you have an iPad and are interested in learning about more about the fundamentals of digital photography, I suggest that you take a look at my Accurate Color iBook in the iTunes Store

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

Posted in Tonality and Appearance, Underpinnings and Core Issues | Tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 14 Comments

Image Tonality and the Histogram- Part Five: Output Levels and Internal Contrast

Graph vs Index HistogramThe Input Gives and the Output Takes Away

If you’ve wondered what the Output Levels are all about, here’s some insights. While the Input Black slider makes the Shadow Point darker and the White slider makes the Highlight Point lighter, their counterpart Output sliders (located below them in the Levels Adjustment panel) do just the opposite. The Output Black slider always makes all dark tones lighter and the Output White slider only makes all light tones darker.

The Input sliders build contrast while the Output sliders flatten contrast. The only obvious purpose in using the Output sliders is to lighten the Shadow Point and three-quarter tones and/or to darken the Highlight Point and quarter tones. While these Output sliders do change the Shadow Point and Highlight Point, they also adversely affect the internal contrast in a quite inarticulate and clumsy manner. To my view they are for the most part useless, as there are much more effective ways to shape an image’s internal contrast ; case in point, the Shadows/Highlights panel.

Shadows-HighlightsThe Shadows/Highlights Panel-

The Shadows/Highlights panel (Image/Adjustments/Shadows/Highlights…) adjusts the tonal range from an internal contrast perspective. The Shadows/Highlights panel does not alter the Shadow or Highlight Points; it rearranges the values in three-quarter tones and quartones respectively. The multi-adjustment sliders in this tool actually affect the three ranges of an image; three-quarter tones, midtones, and quarter tones, and they do so in a totally interactive manner.

Moving the Highlights/Amount slider to the right, for example, affects the internal contrast within the quarter tones without changing the Highlight point itself. This adjustment separates the Shadow point from the next darkest tones in the image. In the same way, the Shadows/Amount slider lightens the three-quarter tones without changing the actual Shadow point itself. This slider establishes the internal contrast in the darkest tones of the image.

The Midtone Contrast slider shifts the tones darker or lighter around the midtone point.

SpiralStaircaseBWThe Shadows/Highlights panel is one of the most powerful tools in the entire software editing arsenal because it affords control over all three critical areas of the tonal range that determine detail and clarity. The visual choreography of these adjustments gives you amazing lattitude in shaping the overall internal contrast of the image. When the Shadows/Highlights controls are coordinated with the three control points of the Levels dialog, the tonal reproduction range is under your control.

The interaction between the Levels panel and the Shadows/Highlights panel control the entire tonal range of the image.

The sixth (and last) post in this series will address the integration and interaction of all three tone range points and all three internal contrast regions. Stay tuned.

This series is a small excerpt from my soon to be released book titled The Digital Image: From Capture to Presentation and Everywhere In-between. If you find this series helpful, I encourage you to watch for the more comprehensive book.

Anyway, that’s the way eye sees it. Feel free to leave a comment and keep the conversation going. If you saw this post listed on a LI group page, add a comment to the listing in that group! Thanks for joining me. If you like this blog, let me know and tell your friends.

This is the fifth entry of the spooky series called Image Tonality and the Histogram. This series is open to the public but I highly recommend that you join the followers of this blog to keep the flow intact. Sign in now as a follower (top right of this page).

See you next time, Herb

hpaynter@imageprep.net

http://imageprep.net

Click the Follow button at the top of the page so you don’t miss any future posts.

AC AVTB CoverPS. if you have an iPad and are interested in learning about more about the fundamentals of digital photography, I suggest that you take a look at my Accurate Color iBook in the iTunes Store

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

Posted in Tonality and Appearance, Underpinnings and Core Issues | Tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 6 Comments

Image Tonality and the Histogram- Part Four: The Magic in the Middle

Before we move on to the middle tone adjustments, allow me to restate and review just a little of the hist-related issues we’ve covered so far. I know for some this will be an unnecessary rehash, but for some that have just joined, it will help them get acclimated.

BlackGammaWhiteLevels

Here’s some image-editing terminology I’d like you to familiarize yourself with. There are three definable Tone Range Points and three Internal Contrast Regions to be recognized. The Shadow point, the three-quarter tones, the middle tones, the Midtone point, the quarter tones, and Highlight point. Dividing the tone range like this will help you understand how to control the ranges using two powerful tool dialogs found both in Photoshop and Lightroom. The two main tone adjustment dialogs in Photoshop are Levels and Shadows/Highlights. I’ll present the tonal range as these two adjustment dialogs address it.

The Levels Panel offers controls over specific individual  Range Points; the Black slider affects the Shadow Point placement, the Gamma slider affects the Midtone point, and the White slider affects the Highlight Point placement.

Both the Black and the White sliders influence the value of the Shadow and Highlight Points respectively. Note that these triangle adjustment sliders are not the Shadow, Midtone, and Highlight points, but they are the tools you will use to adjust and set those points. This is a very important distinction to be remembered. Only if either of the sliders intrude into the graph do they actually set those points to Black or White.

AmyEricWeddingThe difference a midtone move can make is obvious here. Scene averaging metering in the camera resulted in a serious underexposure of the mid and three-quarter tones. The picture on the right was the result of midtone adjustment. Notice that the shadow point and the highlight point were undisturbed with this midtone adjustment.

The Gamma “pointer” points to the desired placement of the 50% value point in the image. It determines where the 50% value will fall in an image- regardless of where the Highlight and Shadow points are located. If the Gamma slider is moved to the left, the middle tones will get shifted toward the right side, resulting in a lightening of the middle tones. Conversely, if the Gamma slider is moved to the right, the middle tones will be shifted toward the three-quarter tones, resulting in the middle tones getting darker. In effect, the midtone point (50%) will be moved within the tonal range. The original value of the Gamma point (1.00) will change when the slider is moved, though the number that appears in the Gamma field is (for most non-mathematicians) of little relevance. What is important to remember is that the new location of this slider will become an absolute 50% value. Note that this value is not the middle of the tonal range, but the location of the 50% value. The next time the Levels Adjustment panel is opened, the Gamma value will once again be 1.00.

The Expanded Middle Tone Range. 

Obviously, an image’s middle tones are located in the “middle” of the image, not the geometric middle, but the middle of the tonal range. Tonal controls (in the Levels dialog box) provide only highlight, midtone, and shadow sliders. In order to fully control tonality, three internal contrast regions should be added.

InternalContrastRegions

ToneRangePoints

I’ll divide the histogram information into three tone range points and three internal contrast regions. These three tonal regions (quarter-tones, midtones, and three-quarter tones) make up what I call “the expanded middle tone range,” and includes everything between the Shadow Point and Highlight Point. This range plays a huge role in the overall tonal balance and the clarity of every digital image. There are several tools in Adobe Photoshop that address and adjust this expanded middle region.

Measuring Light and Managing the Middle 

The image sensors in a digital camera capture light in what is referred to as “linear” fashion. This means that light values are recorded in a purely mathematical fashion; as twice the light passes onto the sensor, twice the voltage is applied to each CMOS/CCD photo cell element. Image sensor devices convert light energy to electrical signals whose numerical values are stored on the camera’s memory card.

Linear CaptureThe human eye interprets light logarithmically. We humans see better in the dark than most cameras. Most of the light-capturing capability of a digital camera sensor is geared toward the bright side of the tonal scale, recording a lot of detail in the lightest areas of the picture. Unfortunately, the middle and three-quarter tones in a scene don’t get recorded with as much accuracy. There just isn’t enough light in those areas to make as much impact on the image sensor. What this means is that pictures taken in medium-to-low lighting situations often appear dark and lacking in detail. This phenomenon is not widely known, or understood when folks print their pictures. Many people simply print their pictures as they appear, right out of the camera, assuming the camera has taken care of that all this technical stuff. O, were it only that simple!

Here’s the simple truth. Unless your photographs are taken under controlled lighting, the darker parts of your pictures will not record the detail that was evident to your eye when you took the picture. To compensate for this problem you must make some simple adjustments to your images before publishing them either in print or display.

To be fair, when digital cameras save files in JPEG format they force images to adapt to a pre-determined adjustment curve in the process. Incidentally, even when files are captured in raw format the camera records the current JPEG-based file settings which get displayed as a “first guess” display in the raw interpreter software. This JPEG setting applies a curve that attempts to boost the middle tones and take a guess as to what the picture really ought to look like.

When a picture was taken under sufficient light this usually works out well. But when the picture was taken in either low light or very strong light (creating a high contrast photograph), these JPEG curves don’t correct the problem. The JPEG solution to lighting correction works about as consistently as buying one-size-fits-all clothing; occasionally both behaviors work out acceptably, but neither should really become a habit.

The next post in this series will address the all-important internal contrast areas of the Three-quarter and Quarter tones in your image. Stay tuned.

This series is a small excerpt from my soon to be released book titled The Digital Image: From Capture to Presentation and Everywhere In-between. If you find this series helpful, imagine what the book will do for you.

That’s the way eye sees it. Feel free to leave a comment and keep the conversation going. If you saw this post listed on a LI group page, add a comment to the listing in that group! Thanks for joining me. If you like this blog, let me know and tell your friends.

This is the fourth entry of the spooky series called Image Tonality and the Histogram. This series is open to the public but I highly recommend that you join the followers of this blog to keep the flow intact. Sign in now as a follower (top right of this page). This does not insinuate that you are a sheep in need of a shepherd! Follow is just a term.

See you next time, Herb

hpaynter@imageprep.net

http://imageprep.net

Click the Follow button at the top of the page so you don’t miss any future posts.

PS. if you have an iPad and are interested in learning about more about the fundamentals of digital photography, I suggest that you take a look at my Accurate Color iBook in the iTunes Store

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

Posted in Tonality and Appearance, Underpinnings and Core Issues | Tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 6 Comments

How Auto White Balance in the Camera and Gray Balance in Editing Can Actually Kill Your Color

Sometimes taking a neutral position on things isn’t really the safe thing to do – sometimes it’s actually downright destructive!

Your camera’s AWB, or Auto White Balance is a typical fallback lighting selection used by most of us because we assume that the camera is smarter than we are, or at least more capable of judging lighting conditions when in a hurry. But assuming that AWB will diagnose lighting and set the proper color temperature could be dangerous. Here’s why.

The first thing to understand is that in the language of RGB color, equal values of red, green, and blue (like red 128, green 128, and blue 128) produce an absolutely neutral gray color. The AWB algorithm in your camera always assumes that there is a detectable neutral gray component in the scene. It then examines the light reflecting from objects in the scene and locks onto the cluster of pixels whose values are closest to equal (regardless of how dissimilar). The AWB mandate then forces those colors to become absolutely neutral value.

This is all well and good IF that cluster of pixels actually is suppose to be neutral in color. The corrected values will then actually improve the balance of color in the image. But, if the scene doesn’t have any neutral component; if there is a bluish-somwhat-gray item in the scene but no actual gray item like the snow scene below, the image processor in your camera will dutifully change that bluish color to neutral gray, and shift all the other colors in the scene at the same time!

Your camera is not smart, it is just efficient and obedient. It will obey anything you tell it to do. It’s a machine, it is not a volitional entity. It will never be “intelligent” in the way that humans are intelligent. It can be programmed to follow a logical sequence, but it cannot “make decisions.” In the snow scene example, you would have given it a command to shift all colors, and it would have obeyed your command and produced bad color; all in the name of Auto White Balance. Hmmm. Don’t be stupid. You’re camera is stupid. You are the intelligent one. You must tell it what to do- NOT the other way around. Hrrumph!

In the same way, there is a time to use your 18% gray card, DataColor SpyderCube or ColorChecker Passport to reference true neutral gray in a scene and set the gray balance in your photos, and there is a time to keep those items in your camera bag. Truth is, neutralizing every image can suck the natural color right out of the scene.

As most of you already know, one of these gray balance tools placed in the photo scene (for an initial test shot) means that it can serve as the gray balance reference for correcting any color shifts in the image. This correction takes place after the capture; when the image is opened in Adobe Lightroom, Camera Raw or Photoshop. This is truly a great way to accurately set the gray balance within a series of photos taken during a single session. In raw interpreter software, all photos can be opened (including the test shot). When the White Balance tool is applied to the reference gray in the test image, all photos open at the time can be color corrected automatically. Great idea! Right?

Yes, unless… the scene contains “emotional” light- candle light, sunrise/sunset, late afternoon or early morning light, nightlife/neon, etc. If the scene to be captured contains this kind of emotional (or mood) lighting, that very mood that made you to capture the image to begin with can be neutered by White Balance.

Disney HotelLate afternoon Florida sun presented a very warm and rich lighting to this shot. I used the Neutral Balance eyedropper in the editing process, choosing the most neutral colored surface I could find to set the White Balance. As a result, I completely destroyed the warmth that attracted me to capture the image in the first place.

Alaska NiteLight

This shot was taken in Fairbanks Alaska on December 28th at 10PM, and captured the surreal lighting that occurs up there at this time of year. The cool shadows that are evident in the foreground are typical of moonlight reflecting off the snow. Setting the camera’s color mode to Daylight, allowing the tungsten lamplight to show warm lighting amidst the cold snow captured exactly what I saw. On the right, the camera’s white balance was set to AWB, assuming that this “automatic” setting would capture the colors of the image faithfully. Oops! AWB actually lost the shivering cold lighting altogether.

In both of the above cases, when white/neutral balance routines were employed, all the ambiance of both scenes was dutifully destroyed. By forcing each unique lighting to be neutralized, both the warmth of the Sun and the frigid look of the night snow were lost.

There is no single, always-right color balance setting on a camera. In fairness, most times, the AWB setting in the camera and gray balance in the editing stage work out very nicely. But occasionally the stupid camera and the powerful editing software needs smarter input. From you.

So what have we learned? There is a time for white-balance just as there is a time for political correctness, BUT to force the strict application of either in every situation can destroy the spirit of free expression. Use gray balance only when emotional/mood lighting isn’t the setting the scene and a gray component is. Too many dramatic scenes get neutered in the name of neutral balance. Protect innocent pixels.

This series is a small excerpt from my soon to be released book titled The Digital Image: From Capture to Presentation and Everywhere In-between. If you find this series helpful, imagine what the book will do for you.

That’s the way eye sees it. Feel free to leave a comment and keep the conversation going. Thanks for joining me this time. If you learned a little something, let me know and tell your friends. Sign up now to have these posts automatically sent to your email address (top right of this page).

See you next time, Herb

hpaynter@imageprep.net

http://imageprep.net

PS. if you have an iPad and are interested in learning about more about the fundamentals of color, light, and digital photography, I suggest that you take a look at my Accurate Color iBook in the iTunes Store

https://itunes.apple.com/us/book/accurate-color-audio-video/id509451372?mt=11

Posted in Tonality and Appearance, Underpinnings and Core Issues | Tagged , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , | 8 Comments