We’re being invaded by France.
HCFR (named after the
homecinema-fr.com forums) is a free video calibration tool for Windows. The program is developed by some French forum DIYers who designed their own colorimeter and needed software to take readings and calibrate their home theater video devices. The software also works with X-Rite DTP-94 and
Colorvision Spyder2 sensors (no support for Eye One Pro yet, though there is hope as Spyder2 support was added in less than a month).
I discovered HCFR just a few days ago through
this AVS Forum Display Calibration Thread. The thread is long and mostly covers discussions of Gamma calculation math, comparisons to other, more expensive, software like Calman, and users posting their results. It was very hard to find concrete answers on how to use the software to calibrate a display. Once I tried the software last night with a Spyder2, I found out why: the interface is very intuitive and it holds your hand through the process.
So you don’t have any barriers to trying out this great software, I’ll list the steps I took to get going and recalibrate my Sanyo PLV-Z3 front projector. (HCFR and the Spyder2 were run under Parallels Win XP emulation on my MacBook Pro.)
Note: What follows is a step-by-step guide to using the HCFR software with a Colorvision Spyder2 sensor and the
GetGray calibration DVD (
my review here). It’s fairly technical and specific to deep calibration of a home theater display. If you’re not into that kind of thing, I encourage you to keep reading and adopt a new hobby that will vastly improve your home theater video experience.
Pre-Calibration - Warm up your projector for 20 minutes
- Install your Spyder2 software, attach the device and let Windows install the drivers.
- Download the latest build of HCFR and install it.
- Copy the “cvspyder.dll” file from the \Program Files\Colorvision\Spyder\ to \Program Files\HCFR\ (it must be in the same directory as the HCFR.exe)
- Load the GetGray DVD to calibrate your display’s basic controls including contrast, brightness, color and tint (if available, my projector grays out color and tint when fed digital HDMI)
Using HCFR with a Spyder2 colorimeter - I set up the Spyder2 device a few feet in front of the projector facing the lens. Adjust the height so the shadow of the meter is in the area of a gray window pattern on your screen. The Spyder needs its blue filter attached, positioned at a 90 degree angle (I was able to MacGyver the Spyder2 to my PVC pipe tripod extension by wrapping some insulated 24 gauge wire around the tripod’s mounting screw and shoving it tight into one of the PVC cross connector’s side openings)
HCFR Preferences - Launch HCFR and click the new document icon (the piece of paper in the upper left corner)
- Step through the new doc wizard choosing “DVD Manual” and “SpyderII”
- Click on the Parameters button for the SpyderII sensor. Under the SpyderII tab make sure the following is set: Calibration Mode: LCD, expand Read Time (ms): 300 and check “Expand read time on dark measurements”
- Select References from the Preferences menu. According to a AVS forum poster when measuring Grayscale set RGB Levels to 16-235, when measuring primary and secondary colors set it to 0-255. For my projector I set the Standard to “HDTV (REC 709)” and Gamma Reference to “from standard” (I guess “from standard” picks up the gamma curve from whatever Standard you have chosen (NTSC, HDTV, PAL or sRGB)). OK out of the Preferences.
- Click on the DVD manual Generator Parameters button and make sure “Blank screen during measure” is unchecked (or you can’t see what your doing).
Initial Grayscale Assessment - Navigate the GetGray DVD to the 10% gray windows starting with 0(% or IRE)
- To do an initial assessment to see how far off your display is from D65 grayscale, click the Measure button in the Grayscale window (it has the 0-100 columns)
- Wait a few seconds for HCFR to initialize the Spyder2 and then follow the dialogue boxes on screen. Each will tell you to navigate to a different gray window on your DVD and click OK to measure 0–100% in 10 steps.
- The Grayscale Table will populate with the 0–100 readings and you’ll get a gamma reading out at the top of the window (my best was 2.23; 2.2 is the target) Update: HCFR reads gamma differently than we’re used to: its 2.2 is really 2.5–6 (too dark); when you select “from standard” just match the curve in the gamma chart, the number you’re shooting for (to achieve the 2.2 HDTV gamma target) is around 1.9.
- With your grayscale measurements you can now look at the RGB Levels Histogram chart.
- If you can adjust your primary colors (not the same RGB gain, offset, color temp and color gamma controls that only adjust grayscale, but your color and tint that control your color matrix’s saturation and tint), switch to 0-255 RGB Levels in Preferences
eferences and click the measure buttons in the Primary and Secondary tables. Follow the on-screen instructions to navigate to 75% color windows of RGB (primaries) and YCM (secondaries). - Now you can marvel at your display’s color gamut and compare how off it is from the HDTV 709 or NTSC 601 color matrixes.
- Save the measurement document to your desktop naming it like this: 20061215_SanyoZ3_Before.chc
Grayscale Measure and Adjust - Create a new Measures document with DVD Manual and SpyderII again. Double check the Sensor Parameters.
- Now it’s time to adjust your grayscale to get as close to a D65 color temperature as possible across all 10 steps of the gray window patterns. Open the Information window and move it the side so you can see it beside your Measures window
- Display a 50% gray pattern on your screen and adjust your basic Color Temp controls as close to D65 as you can (all gains, cuts and gammas should be set to 0) to get in the ballpark of the correct color temp.
- This is where it gets hard and the only thing that will help you is experience and a knowledge of what your display’s calibration controls adjust (I think I’ve spent more time calibrating my Z3 projector than watching movies). Navigate the GetGray DVD to the 30/80% Gray Patterns (or 20/80% if you can get reliable readings at this light level). If you don’t have GetGray, go buy it, the DVD makes the process a breeze when compared to Avia and DVE. With the other DVD’s you’ll quit from too many chapter skips.
- With the 80% pattern on screen click the Play button in HCFR’s Continuous Measures window. After about 10-20 seconds a new window will pop up displaying horizontal luminance, RGB and Delta E line graphs (if you right click on the graph you can change the line colors and thickness, it’s easiest to see what you’re doing with thinner lines). Wait a few seconds for a reading to appear. Ignore luminance and focus on the RGB graph: you want the RGB data points to converge on the 6500 K target dotted white line. Keep an eye on the Delta E magenta trace, you want to get as close to zero as possible but supposedly any reading with less error than 4 is undetectable to the human eye (YMMV).
- Watching both the Continuous measures graphs and the Information window start adjusting your display’s RGB gain controls. HCFR’s Information panel is great as it reads out RGB columns and they’re percentage relative to 100%. To balance the grayscale simply keep adjusting your controls until all three color columns in the bar graph are as close to 100% as possible. Also watch the Delta E, in your initial ballpark measurements it’s okay to switch to the other gray pattern once you’ve hit a Delta E of 4–6. The display’s gains and offsets are interactive so if you get 80% perfect you’ll be off once you adjust 20%. You need to start big and and pop back and forth between patterns to refine your settings, probably making compromises on both sides.
- Once your satisfied with the 20 and 80% measurements, stop the continuous measuring.
- Re-check contrast and brightness levels (adjusting all those cuts and gains can wreak havoc on these basic settings).
- Now measure grayscale again using the 10 gray step process.
- Are you within at less than 4 error across the gray gradient? Probably not. Repeat the continuous measures process again.
- Once you’ve done the best you can, save your display settings to a preset.
- Save your last measures document with the same file name but append “after.”
The screenshot above is the best I could get after three hours of fiddling. HCFR is so easy to use and fast that it let me experiment with my RGB Gamma controls. I adjusted the Blue gamma down a point and Blue color temp up a few points to get flat from 30–80% and as close as I could at 90–100% gray where I run out of Blue (I already have the contrast turned all the way down to get as much blue as I can at the top end). Next calibration session I’ll play with the red and green gammas and see if I can get even flatter.
I hope this guide helps you calibrate your own display with HCFR. Be sure to subscribe to the AVS forum thread to monitor new tips, bugs and software updates.
Tags: Display Devices Home TheaterDisplay Devices,
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12-21-06, 12:25 AM
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