Joe's How-To

Calibration

Joe Doherty

joedohertyphotography@gmail.com

I cut my teeth in a world where serious photographers bought film by the case, sacrificed one roll for a series of tests to determine the true speed and color balance of the batch, and refrigerated the rest. In the twenty years that I’ve been doing digital color photography it’s become progressively easier for the average photographer to recreate that process, and surpass it. Consumerlevel calibration packages and professional services give the rest of us control that was undreamed of 40 years ago.

The purpose of calibration is to standardize the process of color imaging. It provides a “true” baseline of what was photographed, and a system for keeping color and contrast consistent online and in print. It significantly reduces the number of things I need to worry about, giving me more time and energy to create.

The need for calibration has been around for a long time. A clothing designer who commissions a catalog wants her cerulean blue dress to be cerulean blue on the page. A museum wants a catalog with images that faithfully represent the objects in its collection. Both of these have been traditionally accomplished by including a standardized color chart within the image frame, which the printer would then use to calibrate her presses. Now we can incorporate the color chart seamlessly into our workflow at home, calibrating every step in the process.

That said, it took me years to figure out calibration. I was reticent to spend the money and it seemed very complex. But the need to calibrate crept up on me until it became inevitable. Now I calibrate everything – camera, scanner, monitor, printer – and not only do I get consistent color, it makes my workflow much easier.

Ansel Adams once compared color photography to playing an out-of-tune piano. When we calibrate each piece of equipment we tune the piano by creating a profile. Cameras have profiles. If you use Adobe Lightroom you probably already use a profile in the Develop Module, such as Adobe Standard or Adobe Vivid. As you switch between them you can see how they interpret the colors captured by your camera. Vivid is more contrasty and more saturated than Standard, but the underlying relationships among the colors remain unchanged.

I use the X-Rite (now Calibrite) ColorChecker Passport to create custom profiles for my cameras. This involves shooting a color chart and passing it through software that creates a new profile (Figures 1a-1c). The chart is standardized. The software knows what combinations of Red, Green, and Blue to expect from each square, and it creates a profile that adjusts the colors to match what was photographed. In the case of my camera, the custom profile changes the relationship among the colors. It gives me more vivid blues and magentas than the Adobe profiles, while leaving the yellows and oranges unchanged. It is tuning the colors.

The differences are subtle but important. If I’m shooting deep purple lupines on the shore of Lake Tahoe, I want the file I start with to be as close as possible to an accurate representation of the scene (Figure 2). From

Figure 1a. Adobe Standard

Figure 1b. Adobe Vivid that baseline I make artistic judgments about color, saturation, and contrast in my processing. This profile is my default for landscape photography, but I don’t always use it. Sometimes I decide that it isn’t appropriate (in portraiture, for instance), and I use Adobe Neutral.

I also calibrate my scanner. I’ve been scanning film and prints since 2001, but I never calibrated my scanner before last year. I’m so glad I did. It’s made my workflow much easier as I no longer spend hours adjusting the color and contrast of old slides in post-processing. I use the software and calibration targets from Silverfast on an Epson V850 Pro scanner. I won’t go into great detail about it here, but reach out to me if you’d like more information.

Both of the preceding steps are about calibrating image inputs. Now I’ll turn to outputs. The first (and arguably most important) is your monitor. In the simplest terms, for each pixel on your monitor the computer sends an instruction to display a specific value of Red, Green, and Blue (between 0 and 255 for each color in sRGB). The aforementioned cerulean blue, for example, is RGB(42,82,190). This raises an obvious question. Does your monitor display what it was intructed to display?

Figure 2 - Lake Tahoe Lupines

To answer that, you need a colorimeter and calibration software. I use an old X-Rite Colormunki colorimeter, with X-Rite software. Calibrite now sells the ColorChecker Display, which is functionally the same thing.

There are several key steps in calibrating your monitor. With the colorimeter in place on your screen and the software running, use your monitor’s controls to set the brightness to a value between 80 and 100. (Adobe recommends 120, but I have found that my prints come out dark if I set it to that high a value.) You also choose a Gamma value, which is contrast. A value of 2.2 is standard, but since I print on matte papers I use a lower contrast value of 1.8.

At this point your monitor is ready to be calibrated. Your computer sends it instructions to display a flickering parade of different colors. The colorimeter measures each one and passes the RGB values to the software. The software takes what the colorimeter measures and compares it with the original instructions. If the color displayed is different from the instructions, the software adjusts the instructions so that the proper color will be displayed. A profile (.icc file) is created, that contains all of the new instructions for displaying color on that specific monitor. This profile will adjust the values that your computer instructs the monitor to display images so that the intended color is what you see on the monitor. The profile is “tuning” the monitor.

Having a well-tuned monitor is crucial if you want to do more than share your images on social media. For example, printers can only produce what they are sent. A poorly calibrated monitor may result in prints that are too green (monitor has a magenta tint), too dark (monitor is too bright), or too contrasty (monitor is low contrast). In the film era it was easy to blame the lab for these errors, but now the blame may rest on the photographer’s shoulders. The goal, as always, is to have consistency so that what you see in the field and on your screen is If you are printing, the final output is usually on paper or metal. Each printer and paper/metal combination has its own characteristics that affect the color and contrast of your final artwork. Good labs will have a custom profile made for each combination, and they will update it on a regular basis. They do this by printing out a color chart, reading it with a colorimeter, and using software to adjust the instructions sent to the printer so that the output is the intended color. Many labs will publish their printer profiles, which you can download and use to soft-proof your image (both Lightroom and Photoshop allow soft-proofing). That way you can have a pretty good idea what your finished print will look like before it leaves your desktop.

If you are printing your own work, it’s worth the money to have a custom profile created for the printer/paper combination(s) you like to use. We have a Canon Pro 2000 printer, and Velda and I use six different papers on a regular basis, mostly from Hahnemuhle. So we have six different custom printer profiles. It’s very possible to download profiles from the paper manufacturer websites, but from what I’ve seen these are only almost good enough. The difference between “almost good enough” and a custom color profile is the difference between a digital music file and an original vinyl record. A custom profile has greater separation in the highlights and shadows, and it will faithfully render the subtle colors you can see on your calibrated monitor. The difference in the emotional impact can be surprising.

- Joe

Outings 2021: The Sierra Club Re-Opens For Outings

by Joan Schipper, Camera Committee Outings Co-Chair

It was a wretched day in the Spring of 2020 when the Sierra Club told us to wipeout our scheduled outings and meetings. The entire calendar became tentative. In the grand scheme of the pandemic, a few lost outings and the conversion to Zoom meetings was not much hardship. But gosh, it’s good to bring the re-opening news. Effective July 5th the Sierra Club, the Angeles Chapter - the West LA Group and the Camera Committee – are all back in the “business” of organizing and conducting outings!

Of course, things have changed a bit. Notably we will be operating under a new set of evolving COVID Outings Protocols in addition to our usual safety and procedural rules. So, when next you join an outing, expect to see a few changes. Here are somethings to bear in mind.

• Reduced group size. This fits the CamCo nicely as our typically small groups of 8 to 12 are fine. • Masks are required only for indoor close quarters (for example shared vehicles, restaurants, visitor centers) and are optional for outdoors. So, carpools are back! Picnics are fine! Happy hour around the picnic table is restored! Of course, we will all be a bit more conscious of the way we share things. Less dipping, more spooning. Tongs may become a new car camp essential. The mask rules amp-up if there are minors on the trip. Please check the protocols. • We will abide by state, county, and local regulations regarding masks, social-distancing, and occupancy limits. • Vaccinations will not be required and must not be a pre-requisite for inclusion in daytrips. Outings write-ups will carry a reminder that participants may be exposed to other participants who may not be vaccinated. Participants will make their own decisions on whether to join based on this information. • For multiday outings, a medical questionnaire is required and is intended for the leaders’ use in determining fitness for an activity only. Leaders will not share medical information with anyone in or outside the outing unless medical assistance is required. • Also for multiday outings, vaccination is required when overnighting indoors. Exemptions are allowed for persons with a negative PCR (polymerase chain reaction) test 72 hours before trip departure. • All trips: if a participant shows up with COVID symptoms they will be barred from the outing. If symptoms arise during an outing participants will be sent home. An escort out will be provided.

Our Camera Committee leaders are planning and negotiating outings now. Please keep an eye on the Camera Committee Calendar or the Chapter’s Schedule of Activities for outings posted as they are approved. Some leaders post outings on MeetUp or Instagram, as well.

In-person meetings have not yet been approved.

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