Tuesday, 26 February 2019

How to Achieve Monitor Calibration on a Budget

The post How to Achieve Monitor Calibration on a Budget appeared first on Digital Photography School. It was authored by Glenn Harper.

Photographers will often tell you to buy a calibration device for your monitor. It’s the pro thing to do. But do you need one? After all, most of the photo world manages without such a device and still enjoys its pictures.

Monitor calibration X-rite i1 Display Pro

Even among “serious” photographers, many do not have a workflow that fully utilizes calibration. Plus, there are differences between monitors and other devices that calibration cannot always bridge. Color management is not a perfect science.

Calibration versus Profiling

Before going any further, it’s useful to distinguish between calibration and profiling. If you use a hardware device (e.g. colorimeter), it will calibrate your monitor. It then builds a profile based on the calibrated state you just created.
 
A profile describes the monitor so that color-managed programs display colors accurately. Included among calibration settings are black level (brightness), white level (contrast), white point (color temp) and gamma.
Monitor calibration - 3D gamut profile

A custom profile reflects the output of your monitor. This image shows the gamut of my monitor enveloping (mostly) the sRGB color space.

If you don’t own a calibration device, you can still calibrate a monitor manually, but you can’t profile it.

The disadvantages of calibrating a monitor without a device are as follows:

  • Human eyesight is unreliable, so the more you “eyeball” during the calibration process, the further astray you may go.
  • You cannot physically measure the monitor’s condition (e.g. luminance in cd/m2). That means you can’t return it to the same state with each calibration.
Monitor calibration weakness of human vision

This optical illusion demonstrates how easily deceived the eyes are. Squares A and B are identical in tone. Image source: Wikimedia Commons

Do you need a calibration device?

A calibration device isn’t expensive compared to camera bodies and lenses, but the best can cost a couple of hundred dollars or more. The $200 question, then, is do you need one?

Yes: if you use an inkjet printer and want “what-you-see-is-what-you-get” results. In that case, a calibrator is vital. You need accurate profiles for soft-proofing, where you preview print colors before printing.

Yes: if you’re a pro or semi-pro shooting color-critical subjects (e.g. products, fashion).

Probably: if you pay for Photoshop CC, otherwise you are undermining its color capabilities. That said, many Adobe features are not dependent on pin-point color accuracy.

Maybe not: if you’re a stock photographer, since there is no direct client or color-managed chain. One of the world’s biggest libraries, Alamy, has millions of non-color-managed photos on its website.

Maybe not: if you get your prints done at the mall or via the Internet. In that case, the need for a calibration device is less. Why? Because most labs are not color managed. So, a disconnect exists even if you calibrate and profile.

Monitor calibration soft proofing

In Photoshop CC, the ability to “proof colors” depends on an accurate monitor profile as well as an output profile. If you identify a need for this feature, you also need a calibration device.

The need for a calibration device might hinge on your approach. Content is almost everything in photos. Most people viewing your pictures will not be privy to the color you saw on your monitor.

Black & white level calibration

The less you do to a monitor, the less you cause problems like banding, and the better it performs. You needn’t adjust all the settings a monitor has. Even when using a calibration device, many people leave gamma and white point in their “native” condition.

monitor calibration gradient test

You’ll be in a minority if you can view this gradient without seeing any banding, lines or colors (it’s in grayscale). The more you adjust your monitor, the worse this effect will be. But it will only rarely affect photos.

With the above in mind, you could just calibrate the black and white levels. This ensures you can see shadow and highlight detail while editing, preferably in subdued lighting. The process would be something like this:

  • Reset the monitor to default settings.
  • Using black level patches, lower the brightness setting until the darkest patch (#1) is not visible, then brighten it so it is — barely.
  • Using white level patches, adjust contrast if necessary to make the brightest patch (#254) just about visible.

(The #254 pattern on the Lagom site is hard to see except under very subdued light, so #253 will suffice.)

The numbers used to set black and white levels are the same as in an 8-bit image or a levels adjustment (i.e. 0-255). Thus, “0” is pitch black and “255” is the whitest white. All levels in between should be visible.

Most monitors are too bright out of the box. Aside from being poor for editing, this reduces the lifespan of the backlighting.

Free calibration software

There are a couple of free software-only calibration programs. Although they create a profile for you, this profile is not based on the output of your monitor since no measuring takes place. At best, it will be a generic profile taken from your monitor’s EDID data, which may be better than the sRGB alternative.

QuickGamma (Windows)

QuickGamma is a free program that lets you calibrate gamma and black level, but I’d suggest calibrating the latter as described earlier. (I think scrutinizing individual patches is less error prone than squinting at a ramp.) One benefit of QuickGamma v4 is that it can calibrate multiple monitors.

Budget monitor calibration - QuickGamma software

Screenshots of the QuickGamma utility program.

 
If you want to adjust gamma, follow the instructions supplied with the download. I’d advise against adjusting red, green and blue levels unless you see a color cast in the gray bands. Stick to adjusting the gray level if possible. Should you want to adjust the red, blue and green levels, try using this page with the software.

QuickGamma creates a profile based on generic monitor EDID data or sRGB. The first should be more accurate. The profile carries the calibration data, which loads separately on startup. (Windows Desktop does not use the profile.)

Calibrize (Windows)

Calibrize is a simple utility for adjusting black level, white level, and gamma. Unlike QuickGamma, it can only handle single monitors. It doesn’t let you set gray gamma, so you are forced to tweak red, green and blue levels. Adjusting these RGB levels is easier than in QuickGamma, but you’ll still need to squint at the screen to do it.

To build a profile, Calibrize also uses the EDID color data within most monitors. If this is unavailable, I’d guess it uses sRGB.

Budget monitor calibration - Calibrize software

The first and second screens of Calibrize software.

Windows & Mac built-in calibration

Apple and recent Windows operating systems have built-in calibration tools. Personally, I find third-party calibration tools and pages to be better than the Windows utility, particularly regarding the target images used.

I’d suggest these choices for Apple calibration: generic monitor profile, native or 2.2 gamma, native white point. Note again that native settings better preserve the capability of the monitor.

Budget monitor calibration - Windows calibration

This is the image for setting black level (brightness) in Windows. To me, the black “X” seems too bright, which results in a screen that’s too dark.

A paradox exists in calibration in that, the less you do, the better a result you may get. Ironically, you often have to pay for the privilege of doing less in calibration software. Basic programs don’t always allow it.

DisplayCal

Another way you can save money is to buy a basic calibration package and pair the included device with DisplayCal software. In some cases, it’s the complexity of the software that dictates the cost of the calibrator. DisplayCal is one of the best calibration programs, so you’ll gain all the features you need for less money. Be sure to check its compatibility with any device you intend buying.

(DisplayCal is free, though you may wish to contribute towards its upkeep.)

Budget monitor calibration - DisplayCal powered by ArgyllCMS

Screenshots from DisplayCal, which pairs with many calibration devices on the market.

Your call

The aim of this article is not to talk you out of buying a calibrator. If you’re just starting out in photography, you needn’t rush into buying one. Equally, if you don’t like color management or can’t get to grips with it, there is less need to gauge monitor output.

Calibration devices aren’t so expensive, but anyone on a budget has my sympathy. Photography isn’t so cheap. I can also understand the desire to keep things simple. If you can identify with any of that, I hope this article has given you some useful low-cost calibration ideas.

The post How to Achieve Monitor Calibration on a Budget appeared first on Digital Photography School. It was authored by Glenn Harper.



from Digital Photography School https://digital-photography-school.com/monitor-calibration-on-a-budget/

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