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THX and ISF Calibration – is it worth it?

THX and ISF Calibration - The Equipment

The man we challenged to show us this potential was Mark Cheffins, Tech Support for Onkyo Europe, but also a fully qualified and hugely experienced THX-certified professional.

Before letting Mark get down to the business of calibrating both the Onkyo receiver and the Panasonic TV, we had a chat to get a bit of background on exactly what he was going to be doing.

First, the equipment Mark used for his calibration of both the Panasonic TV and the AV receiver – as per minimum THX requirements – included an Xrite1 Pro2 spectroradiometer, an Accupel test pattern generator and, finally, Chromapure’s powerful THX calibrator measuring software.

The calibration process, meanwhile – which can take anything from two hours to an entire day, depending on source numbers – is described by Mark as treating video like a painting, in that he’s trying to make pictures look as close as possible to what the director intended when he first shot a scene.

THX and ISF Calibration

This box of tricks produces perfect test patterns for calibration

THX & ISF Calibration - The Process

This process involves first looking at the ‘canvas’ of the picture: the blacks, whites and greys, adjusting them towards the Rec709 HDTV industry standard (the starting point for all production masters, which comprises chiefly pixel count, frame rate, luma and colour components) with its D65 reference white point.

Once this foundation to the picture is sorted, then it’s onto the three primary and three secondary colours, using the colour meter to adjust colours one at a time until they get as close as possible to their grid references on the Rec709 colour triangle – dubbed the "ordnance survey map" of TV calibration by Mark.

Achieving absolute perfection here is never going to happen, apparently. But so long as a display can get to within a certain tolerance of the perfect figures, it will be close enough to the correct values for any shortcomings to be imperceptible to the human eye.

Not surprisingly given the sophistication and accuracy of the adjustments being made, the more flexibility a screen – and the Onkyo ISF receivers – offers with its adjustments, the closer that screen’s final colour triangle will look to the ‘shark fin’ shape of the Rec709 standard.

THX and ISF Calibration 2

An X-rite1 Pro2 spectroradiometer. Even the basic version costs upwards of £1,000.

You might be wondering at this point why it’s worth paying for a professional calibration of a TV like the Panasonic P50VT50 that’s already THX certified and has THX presets, especially as both THX and the ISF work towards the same end goal. However, this goes back to the point made earlier about a proper calibration taking into account your specific room conditions and the exact nuances of the panel you’ve bought. No TV preset, not even a THX one, can deliver that extra nth degree of perfection you can get with an in-situ calibration.

THX & ISF Calibration - THX on AV Receivers

If you’re also wondering where the THX capabilities of the Onkyo TX-NR5010 come in, we should clarify that at the moment THX certification on receivers currently applies solely to their audio abilities. Audio isn’t the focus of this feature, but suffice it to say that the NR5010’s THX endorsement basically means it has all the tools it needs to sound absolutely amazing. Something our ears are only too happy to confirm.

As Mark settled down to get the calibration process underway, the rest of us hit the pub. Well, come on; Mark not only had to calibrate the Panasonic TV, but he also had to calibrate the HDMI output of the Onkyo receiver differently for each of the Sky box and Panasonic Blu-ray sources going into two of the receiver’s nine HDMI inputs.

A couple of pints of lemonade and a pie later we rolled up back in our test room to find Mark still beavering away but nearly done, looking very satisfied with his three or four hours of work, and raving about the calibration tools of the Panasonic P50VT50 TV, a set he hadn’t worked with before. But what of the results?


May 30, 2013, 2:01 am

Very interesting article, now if only you can less flash adverts on the site so that my not-that-bad laptop can open more than 2 tabs of TR at a time, that'd be great


May 30, 2013, 11:48 am

Interesting, my budget £500 LG has some ISF tools, and I've calibrated it using the internal 'optimiser'. I've not a blu-ray optimiser disk though, so I've not gone further than that. It took about 30mins to do, and well worth it.


May 30, 2013, 3:39 pm

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May 30, 2013, 4:22 pm

Might be worth mentioning AVForum's PicturePerfect web-site: http://www.myperfectpicture... with its guides to TV calibration for novices.

On the other hand, I'm looking forward to TR's budget calibration guide, as my expertise only runs as far as setting the TV into Movie mode and disabling the set's picture processing. Hope the article's up soon.


May 31, 2013, 1:28 am

"motion enhancement systems cause pictures to look unnatural"

I couldn't agree more with this. The first setting i changed when i bought my new tv was to switch off motion plus. I find it particularly weird and distracting when watching dialogue, almost like watching something with the sound out of sync or poorly dubbed.


September 26, 2013, 6:57 pm

If you are truly serious about calibration take a look at the Light Illusion website: http://www.lightillusion.com

This is the calibration system used by the professionals, and now available for hight-end home cinema calibration.


October 9, 2013, 8:15 pm

Unless you are uncomfortable or totally inept at becoming familiar with
the basic and Advanced settings of the newer digital HDTVs, it is
foolish to pay for a "pro" calibration by anyone. It is equally as
foolish to spend hundreds of dollars and hours using consumer grade
hobbyist colorimeters or spectros to make TV settings. It is simply. .. .
NOT necessary . . .period. There will be NO night and day difference
that your eye can see between Media Assisted Setting using a test DVD or
Blu-ray with patterns and a "calibration" performed using equipment. . .
on any TV costing under $3,000 or so.

Also, these are consumer grade TVs we are talking about and usually
using a consumer grade Blu-ray or DVD player in the so called
"calibration" process. True calibration of any scientific device
requires a complete chain of equipment set to standards of known
accuracy. A DVD or Blu-ray player does NOT qualify in this regard and
low cost consumer or hobbyist grade meters and software costing several
hundred dollars are also of dubious accuracy.

I've been working in TVs since a teen well before the hype of
"Calibration" and also have purchased and used calibration meters and
softaware. It is a nice diversion and may let you think you are getting
the "best" picture. Not likely. Unless you own a projection TV system
in a home theater costing multi thousands of dollars, or work in pro
photo work with professional monitors. . .. save yourself some money and
make you own TV settings. The skills and equipment of those using
and selling calibration and meters are very much in doubt and there is
NO way for you to know if your TV is any better than doing it yourself.
The "charts and graphs" provided by such things are pretty, but I've
used them none provide meaningful difference in picture quality.

Ohh... I can hear those who sell such stuff gnashing their teeth, but
folks, I've been working in TV since a teen before all this calibration
hype started. It is simply not necessary. Using a Disney WOW disc,
Digital Video Essentials, Spears & Munsil, etc will provide all you
If you want a "warm fuzzy" feeling that your TV is calibrated and
"accurate" go ahead and pay for meters or a calibration for the status
and bragging rights. But it really isn't necessary at all and you really
have NO way of KNOWING that your TV is really optimized because some
charts, graphs or video tech guru SAYS it is.


March 31, 2014, 2:34 am

What does the receiver actually do? Does it have CMS and 10point white balance for each input??


April 27, 2014, 2:54 am

It depends how you define a "night and day" difference. For me there's a night and day difference on my 65" plasma from a basic DVE calibration to proper gamma, Rec. 709 CMS calibration using HCFR and a spectro.
My wife wouldn't even notice the difference. There's also a huge difference to my audio system after an Audyssey calibration but again my wife probably wouldn't notice the difference....at least not consciously.


February 22, 2015, 4:06 pm

Professional home theater audio and video calibration can be very helpful. Here are some client reviews from a popular calibrator in the US http://www.accucalhd.com/re....

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