HT Designer

Tools for the A/V Pro

ISF Optical Comparator

“Better HDTV Color Fidelity is a Remote Click Away - Simply compare the Grayscale on this App to the same one on your TV!”

Black and White color accuracy is the foundation of all color accuracy.

Using this application, compare the three step grayscale on your Apple device to the same grayscale viewed on your HDTV or to a similar grayscale from a generator.

Use this tool for visual verification of your calibration.

Displaying the grayscale pattern on your display

The easiest way to display the pattern on your TV is to let the application handle it.
On supported iOS devices, use one of the appropriate display cable (Apple Digital AV Adapter, Apple VGA Adapter or similar products) to connect your device to your display.
Once connected, the pattern should appear on your display without any further action.
The “Modes” button allows you to select the resolution of the generated pattern. Depending on your iOS device, iOS software version, adapter cable and display, some resolutions might not be available or display correctly.

If this solution does not work for you, you need to display the pattern through some other means.
If your TV or a device connected to it (such as game console, set-top box, computer) is capable of browsing the web, navigate to this grayscale web page.

Another solution is to download the pattern as a static image and proceed as you would to display a digital photograph on your TV.

Basic application usage

By default, the application display a 3-step grayscale that can be compared with the same pattern on your display.
A single tap on the pattern will toggle the display of the bars at the top and bottom of the screen, reducing the visual clutter and making comparison easier.
A double tap on a single shade of gray will fill the entire screen with that single gray. Double tap again to bring back the 3-step grayscale.

If you are using your iOS device to display the pattern on your display, that pattern “follows” what you are doing on the device, displaying either the grayscale or a single gray.

Pro app

Although we tried to provide the gray colors as close as possible to D65 for all iOS devices, serious calibrators will want to calibrate the screen of their iOS device on a regular basis (we advise to recheck monthly).

Deploy approved colorimeters from the list below on Retina products only, tap the “Calibrate” button and calibrate all three patterns to x = .313, y = .329.

Colorimeters that have passed testing on Retina displays to date

  • X-Rite i1 Pro Spectroradiometers
  • DataColor Spyder 4
  • X-Rite SpectraCal C6
  • Klein K10
  • Photo Research Spectroradiometers
  • Konica Minolta Spectroradiometers

Known issues

We have observed that on first connection of some displays using the Apple Digital AV Adapter (HDMI connection), some form of overscan compensation occurs and the pattern does not fill the entire display. This does not affect the color displayed and should not prevent you from validating your display settings. It seems that changing the resolution used by the application, then coming back to the default/optimal resolution does resolve the issue.


Although this application has been tested on a variety of devices, we cannot guarantee the accuracy of all displays used in Apple devices. Specifically, the grey colors on your specific device might not be accurate to D65 standard.

The ISF HDTV Professional Calibrator Grayscale Optical Comparator application is brought to you by The Imaging Science Foundation and TInSys.

Please contact support [at] htdesigner [dot] eu if you require any additional information or would like to make suggestions on how to improve the product.