TruHu Review: A Simple Way to Calibrate Monitors with a Smartphone

Photographers use their monitors even more than their cameras, probably by a large margin. Even the best monitors should be calibrated to ensure that the colors users see are accurate. However, calibration can be expensive and tedious. TruHu aims to make the calibration process very easy and much more affordable.

What is TruHu?

TruHu is a software and hardware-based monitor calibration tool that uses an iPhone to calibrate a Mac’s built-in display or an external monitor in just a few quick steps. While it may sound too good to be true — it isn’t. PetaPixel chatted with TruHu and took the color calibration tool for a spin, and it works as advertised.

Before getting into how the app works, it’s worth taking a closer look at what TruHu is — and isn’t. Part of the story there is also who the target audience of TruHu is.

The app has been designed with consumers and prosumers in mind rather than advanced, highly technical professionals. If someone already has a color workflow that uses a colorimeter or spectrophotometer, TruHu isn’t for them.

Instead, TruHu is for people who don’t currently have much of a color management workflow but would nonetheless benefit from consistent, accurate color on their monitor, including designers, photographers, videographers, and even people who do a lot of online shopping and want to make sure that the color of a product they see on their computer is the same one they’ll see when they receive a package in the mail.

How Does TruHu Work?

TruHu uses the camera in a user’s iPhone to record a RAW image of a monitor to a Mac with the TruHu desktop app installed and opened. The app on the iPhone and Mac takes users through multiple steps, including capturing two images, one of a grayscale box and the other of a colorful box.

The RAW image is sent to the cloud, processed using fancy software, and then sent to the computer where the app then applies the resulting .icc color profile at the macOS system level, like what would happen if a user created their own .icc profile using Mac’s calibration tools or specialized hardware.

TruHu’s developers built specific look-up tables (LUTs) for each supported iPhone model and use the RAW color data the iPhone camera captures to measure the spectral response delivered by the monitor.

Because of this approach, which doesn’t require the phone’s camera to be against the display like dedicated calibration hardware is, it’s essential that users don’t have any glare on their monitor. However, even if they do, each profile created by TruHu won’t venture too far from a manufacturer’s built-in profile. In chatting with PetaPixel, TruHu’s founder, Clark Omholt, says that the company doesn’t want customers to shoot themselves in the foot, so there’s only so far the app will take a profile.

Of course, these guardrails aren’t a hindrance to achieving a good calibration, they only prevent a user from accidentally creating an awful one because they didn’t adhere to TruHu’s best practices.

While there’s no need to dive into the most technical, nitty-gritty details about how TruHu works, the gist is that the app communicates with itself across multiple devices using the cloud as an intermediary. Within the cloud, the magic happens.

The RAW image data captured by the iPhone’s camera is measured, analyzed, and evaluated by an algorithm inside the cloud, and then the process produces a color profile that ensures that a computer monitor is properly and accurately rendering color. As is often the case, something that sounds so simple is very complex — the app has been about two years in the making.

The Results

Admittedly, I came into the demo with a healthy dose of skepticism. Other companies have achieved something similar in very limited ways. For example, Samsung has a similar sort of app that works with select smart televisions and Samsung smartphones. But again, that’s very limited. Never has a company achieved something quite like what TruHu is doing, and certainly not at this scale.

Whenever something new comes along that breaks new ground, I expect some significant caveat, like “It works, but…” and to Sir Mix-a-Lot’s satisfaction, the “but” is often massive, and my optimism or excitement is quickly dampened.

Not with TruHu. Coming at it from the perspective of someone who has long espoused the benefits of monitor calibration for photo editing and printing, and who owns a few different colorimeters, TruHu comes shockingly close to matching the dedicated color management solutions that require expensive and tedious hardware and software.

TruHu is $29.99 for the first year. A Datacolor SpyderX Pro Color Calibration tool is $145. A Calibrite ColorChecker Display — the one we use here at PetaPixel for our monitor evaluations — is a bit more at $169. That’s a big price difference, but the contrast in results is much smaller. Calibration hardware can cost much more than that, too, and highly sophisticated color management solutions can run into the thousands.

There are some limitations to TruHu from a photography perspective, although color accuracy isn’t one of them. While there’s a bit of debate about the proper monitor brightness for photo editing, 120 cd/m2 is a popular target. I keep my office dim and suffer from annoying eye floaters, so I keep my monitors significantly darker, around 100 cd/m2, which works fine for photo editing and home printing.

The point is, regardless of the selected brightness value, I can designate a monitor luminance using colorimeter applications, and the hardware and software work together to meet my target. Perhaps just as importantly, I get to select a target, and dedicated colorimeters tell me the precise results.

With TruHu, the app just tells users to pick the appropriate brightness for their setting, and that’s it. TruHu says that this is best for a larger group of users, especially ones in bright environments where a “proper” monitor brightness may be unusable or look worse to users. Once a user has adjusted their monitor brightness — and disabled any automatic brightness or Night Shift settings, which the app tells users about — it’s time for the next step.

My monitor allows me to set brightness to a specific luminance value, which is excellent, but TruHu won’t verify that the monitor’s brightness is correct or tell me anything about its brightness. Monitors change over time, especially concerning luminance, so I wish that TruHu would at least measure the luminance and let me know if my settings are accurate.

However, TruHu wants to avoid opening that can of worms, and I respect that. The app then asks the user to select a white point, which is very important to achieve good, accurate color. The default is 6,500 Kelvin (D65), but users can go from 5,000 to 8,000K. I use a D65 white point, but I tested other ones to see if TruHu would noticeably affect the white balance. Sure enough, it did. Also, using a color calibration tool, 6,500K within TruHu looks identical to my 6,500K target.

After grabbing the two required pictures within TruHu on my iPhone, the desktop app almost instantly created a color profile for my display. While I can’t offer much by way of proof, I can say that the difference between the TruHu .icc profile and my calibrator’s .icc profile is minimal — practically indistinguishable.

That might not seem like such a big deal, but to put it in perspective, I didn’t need to plug anything in — which requires a USB dongle with modern Macs — and the entire process took about a minute rather than 10 to 15 minutes. That means I got similar results in a fraction of the time, at a fraction of the cost, and using just my phone.

Admittedly, TruHu offers less precision and control than some dedicated calibration systems, and it doesn’t allow me to measure my monitor’s brightness or even see its spectral response. TruHu creates a good profile, but it doesn’t offer me much by way of control or information. I also can’t use TruHu to test different sections of a monitor, which can be very important when doing color-precise work. Granted, entry-level monitor calibrators rarely enable testing of different areas of a display either.

However, considering that TruHu is aimed at people that don’t have a color management solution, I am willing to accept these limitations. If the app did everything that I want it to do, then it wouldn’t be $30 per year and certainly wouldn’t be as simple to use.

Should Photographers Use TruHu?

As impressive as the app is, whether a photographer should use it depends upon their existing color management solution, namely, if there is one in place. If someone has a colorimeter, there’s no reason to use TruHu, unless you hate getting the accessory out and plugging it in.

For photographers whose eyes glaze over when someone talks about color profiles and monitor calibration — and there are a lot of them out there — then TruHu is the perfect gateway to a better and more consistent color. For many users, it’s the last calibration technology they’ll need.

TruHu takes only a few minutes to install and use, and then the app will remind you every so often to do it again, and that’s that. It’s easy. If you can use a computer and an iPhone, you can use TruHu.

You can also try it for free and see if you like it. You can’t use the profile the free version creates, but you can see how the app works and see if the results are worth it.

Pricing

As mentioned, TruHu is $29.99 per year. That’s an “introductory” price, so subsequent years will be $49.99 annually. There’s no lifetime license option.

TruHu is free to try, and the apps themselves for iOS and macOS are free to download. The Windows/Android versions are in the works, and should be available sometime this year.

Who Else is TruHu Good For?

Beyond photographers and videographers, TruHu is also a good choice for designers, illustrators, and businesses. For remote work, it’s not possible to calibrate everyone’s monitors using a calibration tool. TruHu is excellent because everyone just needs an iPhone and Mac. It’s also a good choice for hybrid workers who maybe have a high-end calibrated monitor at the office but don’t have a calibration system for their home, or vice versa. TruHu sidesteps that problem with ease. TruHu is tied to an account, not an individual device, and .icc profiles are created at a system level.

System Requirements

A major limitation of TruHu is that it requires an iPhone and macOS. However, it works with iPhone 7 and newer, which is almost every iPhone still in use today.

TruHu is working on making the app for Windows computers and Android-powered smartphones, and the company plans to launch the Windows/Android version this year.

Are There Alternatives?

Yes and no. There are alternative ways to calibrate monitors, but nothing works in the same way as TruHu.

Typical colorimeters, like the Datacolor Spyder X and the Calibrite Color Checker, are alternative ways to calibrate monitors. They cost more and require specialized hardware. However, they offer more control than TruHu, even if the final results for many customers may not appear much different.

Should You Buy It?

Yes. TruHu is a simple and effective way to calibrate monitors and ensure accurate color across a photography or videography workflow.