JVC Projector Calibration

[Steven_James89]

Hey guys,

 

I have attached some pre/post calibration results for my JVC X7000.
Would like to know (a) what does everything mean (b) what are we aiming to achieve for post calibration in regards to the charts.

Really want to learn more about this as im planning on doing an auto cal on my new JVC X7900.

 

Silly question but considering the new projector has been set up in the same location/same room/same environment, could I just apply the X7000 calibration results to the X7900 with a few tweaks here and there?

 

Any feedback is greatly appreciated or any links to understand his further.

[IMDave]

I know bugger all about Calman, on a more general note, what you are effectively calibrating is the lamp.

So no, you cannot use the X7000 cal settings on the new pj.

They may turn out to be very similar. But that will be by accident more than design. 

[Steven_James89]

Thanks mate, yeah I'm just trying to get a better understanding of the graphs.. what do they mean? what are we trying to achieve? does adjusting deep settings alter this? how good is auto cal on the JVC...etc. looking to purchase Spyder 5 but hesitate with some people ending with pinkish screen results.

[CAVX]

On 05/02/2018 at 1:35 PM, Steven_James89 said:

Thanks mate, yeah I'm just trying to get a better understanding of the graphs.. what do they mean? what are we trying to achieve? does adjusting deep settings alter this? how good is auto cal on the JVC...etc. looking to purchase Spyder 5 but hesitate with some people ending with pinkish screen results.

I'll try and keep this simple.

RGB balance is the grey scale tracking from black to white.  Ideally, you seek a point (shown on the CIE diagram) of D6500K.  To get there, you need to find the precise x,y point where x = 0.313 and y = 0.329.  The grey scale should be flat from 0 -100 generally expressed as percentages or IRE (Institute of Radio Engineers).   Grey Scale is also expressed as numbers from RGB0 - RGB255.  

 

The differences between SDR and HDR are as follows - 

 

SDR has a range from video black of  PC RGB16 to video white or RGB 235 (even though the range goes up to 255) to remain backwards compatible with CRT.

The peak white for SDR is said to be no brighter than 100 nits or 29.29FL.

 

HDR still covers the same range but does it much finer steps (0 to 1024 in a 10bit system).  This gives finer gradients and hopefully banding is not visible.  

The main difference is that the whites continue well past 100nits out to 10,000nits.

 

The reality is that an OLED TV might push out past 500nits and an LCD TV might be capable of 1000 nits.  A projector is doing extremely well if it can push out 100nits.

 

The lumanance chart is showing 100nits. 

 

For colour the CALMAN shows both a 2D xy and the Y is shown in the chart below that.  The x,y points are what we typically use to compare the size and mapping of of the colour gamut.   The Y is the lumanance or how bright each colour is.  Your chart shows this as a flat line meaning all Y values are at 100%.    

Where HD video uses rec709 colour, UHD can use a colour gamut far larger like P3 (used by D-Cinema) and BT2020.  Rec 709 is 75% of P3 and P3 is 75% of 2020.  

Using PQ gamma, each colour is supposed to be able to reach 10,000nits.