[Brian Hampton]

I don't think HCFR leaves Y out of color DE. Currently I have green with perfect xy and 30% Y error and de is high.


I'm not even convinced HCFR calculates color de wrong. This is something I could investigate. It's easy enough to manually put in the data thats correct and then modify it different ways.

 

[JohnAd]



Quote:
Originally Posted by Kilgore /forum/post/21642540


Continuous real-time 11 point gamma display.

Can you give a bit more of a description of what you mean, how you would see this working? Do you mean you pick which point you are doing and then working with continuous readings and a target?


Would you expect to normalize the luminance of the 100% or the 109% point?


So do 0% to get black, 109% to get peak and then do 100%, 90%... 10%


John

 

[EmilG]

Sure would be nice to be able to put up 75%, 50% and 25% saturation points on the gamut chart since many use 75%.

This way using Continuous Measure to align hue and saturation would be simplified.

 

[JohnAd]



Quote:
Originally Posted by Brian Hampton /forum/post/21642977


I don't think HCFR leaves Y out of color DE. Currently I have green with perfect xy and 30% Y error and de is high.


I'm not even convinced HCFR calculates color de wrong. This is something I could investigate. It's easy enough to manually put in the data thats correct and then modify it different ways.

Looking through the code there seems to be some quite confusing labeling going on.


In the advanced tab, there are 2 settings at the bottom


The first of those "Do not use luminance in delta E formula (V1.x)" corresponds to the internal setting Use Old DeltaE so should be off.


The second of those is "Use gamma reference to compute gray scale delta E" should be on if you want Y to be included in dE and off if you don't.


The default for both is off so unless you change something Y is not included in dE.

 

[dominickwok]



Quote:
Originally Posted by JohnAd /forum/post/0


Can you give a bit more of a description of what you mean, how you would see this working? Do you mean you pick which point you are doing and then working with continuous readings and a target?


Would you expect to normalize the luminance of the 100% or the 109% point?


So do 0% to get black, 109% to get peak and then do 100%, 90%... 10%


John

I think what he means is actually a 9-point gamma real-time tracking for 10% - 90% (0% black and 100% white have no gamma value). Right now it is not convenient to do that because the target Y values are calculated only after a complete grayscale run from 0% to 100%. If I'm only adjusting the gamma of, say the 70% point, what I need to measure is the 0% Y value and the 100% Y value, and the target Y for my 70% point should be calculated and show up on the screen for me to shoot for that value (using continuous measure).

 

[Brian Hampton]



Quote:
Originally Posted by dominickwok /forum/post/21643195


I think what he means is actually a 9-point gamma real-time tracking for 10% - 90% (0% black and 100% white have no gamma value). Right now it is not convenient to do that because the target Y values are calculated only after a complete grayscale run from 0% to 100%. If I'm only adjusting the gamma of, say the 70% point, what I need to measure is the 0% Y value and the 100% Y value, and the target Y for my 70% point should be calculated and show up on the screen for me to shoot for that value (using continuous measure).

Yeah,... I use a secondary excel spreadsheet that I put in the 100% Y value and it gives me the rest for any gamma target. This way I can adjust other values without running the whole set of measurements.


There's no lack of things do suggest for HCFR since it's not been updated in years. Just enhancing the meter support would be HUGE.


-Brian

 

[deandob]

[/QUOTE=Brian Hampton;21643233]Yeah,... I use a secondary excel spreadsheet that I put in the 100% Y value and it gives me the rest for any gamma target. This way I can adjust other values without running the whole set of measurements.



-Brian[/quote]


Same here - having to use a separate spreadsheet is a pain with HCFR, would be great to be able to use the HCFR 100%Y value and have the program calculate at least the 100% & 75% saturation levels for a gamma target, should not be too hard to do. Link to spreadsheet that shows how this is done: http://www.avsforum.com/avs-vb/showt...7#post15607437

Also support for the new Display-3 would be great. Just adding these two features would make HCFR useful for most of the basic DIY calibration tasks.

 

[Kilgore]



Quote:
Originally Posted by JohnAd /forum/post/21642981


Can you give a bit more of a description of what you mean, how you would see this working? Do you mean you pick which point you are doing and then working with continuous readings and a target?


Would you expect to normalize the luminance of the 100% or the 109% point?


So do 0% to get black, 109% to get peak and then do 100%, 90%... 10%


John

I want it to be able to take the 100% Y reading and calculate the appropriate Y reading for each level down to 10% (90%, 80%, 70%, etc) so that I can adjust the level of Y at each level to match the calculated target to achieve the gamma I want at each level.


...and I want to be able to make these adjustments in real time without having to refer to a spreadsheet..


As it stands now, all you can do is do a full set of grayscale measures and see what the (average) gamma is and see the curve displayed on a chart. You can't see the results of any gamma corrections you make in real time. You can just guess at some corrections and then do another full set of grayscale measures, and keep repeating until you get a gamma reading you want.

 

[Kilgore]



Quote:
Originally Posted by dominickwok /forum/post/21643195


I think what he means is actually a 9-point gamma real-time tracking for 10% - 90% (0% black and 100% white have no gamma value). Right now it is not convenient to do that because the target Y values are calculated only after a complete grayscale run from 0% to 100%. If I'm only adjusting the gamma of, say the 70% point, what I need to measure is the 0% Y value and the 100% Y value, and the target Y for my 70% point should be calculated and show up on the screen for me to shoot for that value (using continuous measure).

Yes, that is what I meant.

 

[dominickwok]



Quote:
Originally Posted by Kilgore /forum/post/21646578


You can just guess at some corrections and then do another full set of grayscale measures, and keep repeating until you get a gamma reading you want.

This may not be necessary. You can display the %stimulus pattern in question, e.g. a 70% window, use free measurement to observe the measured xyY value while changing your gamma setting for 70% in the TV/projector, and align the measured Y to the target gamma Y as shown in the measurement table.


If you suspect the 100% luminance level is changed, you can check the box "Editable data" in the measurement table, do a free measurement at the 100% pattern, copy-and-paste the measured xyY data (on the left side of the screen) to the column of 100% data, and all the target gamma Y values for 10% - 90% will be refreshed.


Of course, this will work only if you have done a complete grayscale run; and the process is too clumbersome.

 

[Kilgore]



Quote:
Originally Posted by dominickwok /forum/post/21647469


This may not be necessary. You can display the %stimulus pattern in question, e.g. a 70% window, use free measurement to observe the measured xyY value while changing your gamma setting for 70% in the TV/projector, and align the measured Y to the target gamma Y as shown in the measurement table.


If you suspect the 100% luminance level is changed, you can check the box "Editable data" in the measurement table, do a free measurement at the 100% pattern, copy-and-paste the measured xyY data (on the left side of the screen) to the column of 100% data, and all the target gamma Y values for 10% - 90% will be refreshed.


Of course, this will work only if you have done a complete grayscale run; and the process is too clumbersome.

Either way, adjusting gamma in HCFR is a PITA. I use ChromaPure, and adjusting gamma in it is a breeze.

 

[JohnAd]



Quote:
Originally Posted by ascl /forum/post/21642529


Ah this is excellent to see. I'd be very keen on a mac port, and likely to contribute to it, so hopefully the source can be found...!

Some excellent news, I've been in contact with Jerome who wrote the mac version and he's given me the latest source. I'll be adding that to git soon and then making sure I can get it compiled at the weekend.


John

 

[JohnAd]

I think I'm getting the picture on the gamma.


So basic processes that should be as easy as possible are:

1. setting white point
2. setting primaries
3. setting gamma

John

 

[zoyd]

Current workflow for gamma adjustment is not that bad. The 10-90 target Y's appear in the table data after a grayscale run and then you use real-time measures to adjust. I guess it would be nice to have a real-time graphical display of the measure vs. the target rather than comparing two numbers.

 

[JohnAd]



Quote:
Originally Posted by zoyd /forum/post/21647943


I guess it would be nice to have a real-time graphical display of the measure vs. the target rather than comparing two numbers.

For gamma the current dart target for the xy and some kind of 1-d error indicator for the Y would seem sensible.


John

 

[alluringreality]



Quote:
Originally Posted by JohnAd /forum/post/21647738


as easy as possible

setting primaries

Another thing that seems to confuse new users of HCFR is that reducing Delta E for colors does not necessarily mean that you're coming closer to a target calibration. For example if you have a clearly oversaturated green and limited display controls the formula in HCFR generally suggests that you can reduce Delta E by lowering the brightness of green. My personal opinion is that such a trend is likely questionable, if not simply incorrect, and the newer Delta E formulas don't share the same trend of implying that drastically changing brightness may result in less color error.

 

[bruce]

I would love to see the Y value reported on the CIE diagram when in continuous read mode, so you could see the effect on Y while adjusting saturation and hue.


The CIE diagram offers great real-time feedback when in continuous read mode when adjusting CMS controls for hue and saturation. Unfortunately, the hue and saturation affect the Y luminance value (which must be read off the Meaured tab). It would be nice to see it on the CIE diagram.


bruce

 

[JohnAd]

Thanks for all the comments so far, plenty to think about there.


The intergration of the new meters is coming on pretty well, there will probably be a release with just the new meter support next week sometime. The main annoyance will be the need to install different drivers but in this case that's the price of freedom....


After that I'll start looking at some of the other issues.


John

 

[deandob]

Thank you John. For freeware HCFR is pretty impressive, and having a couple of these features added & support for newer meters will be much appreciated.


I have programming experience VB mostly, C++ is pretty rusty, so could help , but I'm probably more help testing (although I'm not a calibration expert).

 

[JohnAd]



Quote:
Originally Posted by deandob /forum/post/21650514


Thank you John. For freeware HCFR is pretty impressive, and having a couple of these features added & support for newer meters will be much appreciated.


I have programming experience VB mostly, C++ is pretty rusty, so could help , but I'm probably more help testing (although I'm not a calibration expert).

Great, testing is always helpful, also what meters do you have access to? I've got access to a colormunki and several i1Displays. Confirming it works with others before releaseing more widely would be very handy.


Signing up to the dev list is the best way of getting access to the hot off the press stuff.


John