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@Dreamliner @atabea Thank you both for your advice. When I have time I'll sure get my hands dirty with learning to create my own custom curves. Meanwhile, I ran Autocals for SDR and HDR. I haven't tested my SDR calibration, but I did for HDR and it looks darn good to me. I ran a color only calibration for BT2020, imported Manni's 190-1000-4000 gamma curve, High lamp, 0 iris and popped in Passengers 4K........Picture looked great!
 
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OK so I am about to distill a ton of research and experimentation into a very simple process you can follow to create your own custom curve. I am not going to go into the details of where to get the tools and setting them up - that's been covered elsewhere. Also this is not meant to be "all encompassing" so you may need to do more research to understand some of what I'm talking about here. Rather, the goal is to give you the quick steps to get your own curve up and running. So here ya go:

[Note that much of this is from memory - I need to revisit this and double check a few things, so for now consider this a draft]

1. Start with the latest version of Arve's tool from the wip branch.

2. Select a custom gamma slot, such as Custom 1, in the JVC. Change the correction value to "Import"

3. Set your contrast and brightness to 0 in the JVC and in your sources such as Panasonic UB900. This assumes Standard HDMI type.

4. Run Arve's tool menu.py.

5. Select lp, then option 2. This loads a default HDR curve into the tool.

6. Make sure your source is outputting HDR and not SDR BT2020.

7. Bring up a HDR image you want to test with. I use the "sky scene" in Pan at 18:55. However this scene only resolves up to 2750 nits. Although this is a good choice for those with large screens and low peak white nits (below 100, I only have about 45), if you have above 100 nits you'll be better off using a scene that resolves up to 4000 nits. Mad Max is often mentioned for this. You can find examples of scenes in a picture comparison thread several pages back. Note that I recommend using an actual scene (paused) from a HDR movie for this and not a white clipping pattern. The reason is because the clipping pattern can still show bars but crush in between. The best way to determine this is therefore with an actual scene. Certainly you can try it with a clipping pattern if you'd like to compare the results to doing the same approach with a scene from a movie, but if you only want to do it once, use a movie scene not a pattern for this.

8. Enter ga in the tool (gamma adjust). This will bring up a new menu.

9. Use option 3 "tune with contrast". This will load the tool's default HDR curve into the JVC and prepare itself for your contrast control adjustment (see next step).

10. Your image will be highly crushed in this initial state. See attached pan-sky-initial image. Lower contrast to the point where the crush is gone. See pan-sky-contrast-fully-tuned image - this is how mine looks once fully adjusted for no crush. Just keep dropping it until you feel that no image detail is being lost due to "bloom". When you find that point, raise contrast again a click or two and confirm that the blooming starts, lower it again - the point is toe just confirm that you have the right point. In my setup I think I had to drop contrast to around -18 or -20.

11. When you are done adjusting contrast, press Enter on Arve's tool (which is waiting for you to do so to tell it you're done adjusting contrast). This is where the magic happens... It will readjust your curve based on the brightness you need, send the new curve to the pj, and then automatically reset the JVC brightness back to 0 for you.

12. It gives you a chance to repeat this process, which may be necessary to fine tune a click or two. Change contrast a few clicks in either direction. Most likely you will be good now at 0 if you got it right in the first place (step 10). If you adjust contrast, go to step 11 and repeat. If you leave contrast at 0, when you hit return in the tool it'll exit this adjustment phase.

Tip: From early experimentation it seems that you can get extra brightness without as much crushing on 1000 nit master titles. Therefore if you have low nits like me, it may be worthwhile to have two "go to" curves - one for 1000 nit titles and one for 4000 nit titles. So repeat this whole process (all steps here) a 2nd time, but using a 1000 nit title like Lucy. The result will be a brighter curve that may work well on 1000 nit titles.

As a general guide, expect to lower contrast to about -17 to -23 for 4000 nit titles (crushing beyond 2750) and to about -5 to -7 for 1000 nit titles. Let your eyes guide you on the scenes, but that should give you a rough idea if you are in the right ballpark.

Tip [URL=http://www.avsforum.com/forum/usertag.php?do=list&action=hash&hash=2]#2 :[/URL] When using the contrast control to set the contrast so there is no clipping, you will likely create a picture that looks nice and properly saturated, but is too dim, particularly if you have less than 100 nits to start with. Therefore I recommend doing one curve with contrast set ideally, again, likely you will find that be around -23 to -17. After completing all the steps listed in this guide, repeat it from scratch again, but this time purposely crush some of the scene, perhaps with a contrast setting around -12 to -15. Finish all the steps here again, but save this into another preset. Then repeat everything once again, but with targeting a 1000 nit master and clipping around 1000, which will be around -5 to -7 as mentioned above. Save that into the 3rd slot. Then as you watch movies play around and see which one you will like best. Hint/spoiler alert: You will like the brightest one best. :) However you will crush some bright scenes as a result. So you'll have to decide what is an acceptable level of tradeoff. By having 3 different curves you can try any of them A/B to pick your favorite. You can even use the 1000 nit target curve for 4000 nit masters (but will crush them quite a bit) and still find it VERY pleasing, if you don't mind the crush.

13. At this point your curve is mainly complete. However this is where manually tweaking can be done. You can try changing the soft clip value (sc) lower or higher, and or changing the se value to control how steep the clip is. I lowered my sc from the auto setting and lower my se from 0.75 to 0.5. This further helped to tame some minor blooming I had in the highlights otherwise. For instance, after my contrast was tuned I still had some pretty heavy blooming in highlights. See pan-hand-highlight-high image. After lowering my sc and se I was able to tame it, without sacrificing much if any overall image brightness. See pan-hand-highlight-medium for the end result. Look at Pan's hand (wrist really) in both of those pics. Notice the bloom is tamed (somewhat) in the medium one. Look at the clouds above his hand in both pics - you can see how the excess bloom is tamed there as well.

Note: You will have to walk a fine line between how much crush you are willing to take for a brighter picture, or put another way, how dim of a picture you are willing to accept to minimize crush. The brighter the picture, not only is there more crush, but the picture begins to desaturate. In these two sky image examples those are at both ends - too high and too low. This picture is rather dim in the low one. So in reality I wind up cheating-up some by introducing some desaturation and some crush, but no where close to what the initial sky looks like. I have a few versions of this saved into different presets so I can change the curve to taste based on the movie.

14. Now it's time to fine tune the Brightness, tho we will not do that with any controls - just with Arve's tool. Leave brightness at 0 in JVC and elsewhere. Don't touch those controls... Bring up Ray's black clipping pattern, the 2nd one with the large bars. Pause it with the bars showing so the clip doesn't end on you while you are working on it, but hit play to help you see what's flashing or not as you make adjustments, then rewind to the beginning of the clip so it doesn't end on you as you work with hit. The idea here is to purposely crush black so that 0.005 nits is the black floor instead of 0. This should provide a lower black floor for content mastered at 0.005 black (about 70% of the content) while also not having any detrimental impact to content mastered at 0 nit black. To do this we target bars 77 and below to not be flashing, and 81 and above to be flashing.

15. Enter the command "bbi 0.005" to set this as your black floor for content. Issue Pw command to write this to the JVC. You will likely find that bar 81 and possibly higher bars are not visible/flashing. In that case use the "bbo" command to add just a touch of brightness, then send to the JVC with Pw command. Try something very small at first, like 0.002. You want to get to the point where you can't see bar 77 but can see bar 81. Keep trying bbo values and Pw until bar 81 shows but bar 77 does not.

16. At this point you are done. Use the command "s filename" to save your curve to your PC. Later you can use "lf filename" to reload your curve back into the tool and write it back to the pj, in case you want to work on it some more (or in case you want to overwrite it temporarily in the pj but then come back to it later).

17. Experiment. Try the same process over, but perhaps crushing your contrast-setting scene a bit more to give you more brightness. And or play with sc or se. Write curves into other custom gamma slots. Then bring up scenes and switch between them in the JVC. You may find that some curves work better for dark vs brighter movies.

Hope this helps!

Edit 3/14/17: Added screenshots and further clarification to steps 9-13.

Edit 3/15/17: Added more details on using bbi and bbo to set the proper black level; added more details on contrast fine tuning and idea of designing curves for 1000 vs 4000 nit titles.

Edit: 3/16/17: Added clarification to say to use a movie scene for the contrast tuning, not a white clipping pattern.

Edit: 3/17/17: Added tip #2 above, for ideas on how to generate curves with different brightness levels to pick from.

I'm about to create my own custom curve on my JVC X5000, and I'm studying the Speed Guide above. I need some hand-holding though :) First, some questions:

1. The JVC needs to be connected to my network, correct? To do this, I just plug in a LAN-cable from my router into the JVC?
2. My projector has been professionally calibrated. Will creating a new custom curve change any of the calibration settings? I'm asking because in the guide I'm instructed to reset the Contrast and Brightness to 0 and then adjust to match an optimal HDR level. But if I do this, I will change the originally calibrated values for standard Blu-ray. Or should I choose a new empty Picture Mode?

Sorry for the newbie questions...
 

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I'm about to create my own custom curve on my JVC X5000, and I'm studying the Speed Guide above. I need some hand-holding though :) First, some questions:

1. The JVC needs to be connected to my network, correct? To do this, I just plug in a LAN-cable from my router into the JVC?
2. My projector has been professionally calibrated. Will creating a new custom curve change any of the calibration settings? I'm asking because in the guide I'm instructed to reset the Contrast and Brightness to 0 and then adjust to match an optimal HDR level. But if I do this, I will change the originally calibrated values for standard Blu-ray. Or should I choose a new empty Picture Mode?

Sorry for the newbie questions...
1 - yes, i connect min to my router. you will need to go to the network setting on the JVC to read off the IP address

2 - when it was calibrated did the calibrate for HDR? Did they calibrate BT2020 color? If so then the color should be calibrated, you are only adding a new gamma cure with lovingdvd's speed guide. This will not effect any current calibrations, you are just adding new gamma curves to be stored in Custom 1, 2 or 3 gamma slots to be used with HDR.
 

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1 - yes, i connect min to my router. you will need to go to the network setting on the JVC to read off the IP address

2 - when it was calibrated did the calibrate for HDR? Did they calibrate BT2020 color? If so then the color should be calibrated, you are only adding a new gamma cure with lovingdvd's speed guide. This will not effect any current calibrations, you are just adding new gamma curves to be stored in Custom 1, 2 or 3 gamma slots to be used with HDR.
Thanks!

2. I'm not sure about which color space was calibrated, I need to check with the calibration guy (on vacation as of now). Unless I can see this for myself? The settings for Color in the menu is set to slot "Custom 1" but when looking inside that slot the color management is set to OFF (?).
 

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I watch low lamp wide open for dark films (Underworld, Bourne, etc) to get best blacks and high lamp wide open with brighter/more colorful films (animation) to get the widest gamut/best highlights, unless it's a drama with lots of quiet moments, in which case I use low lamp as the fan noise can be distracting when the soundtrack is quiet.
Hi Manni,

I have a question I calibrated HDR10 with Calman and added a 6.8 multiplier Y screen offset. When it was completed I read 118nits with the offset. I check the nits with the offset back to 0 and I read 127 nits.

What is the actual nits reading?

Thanks
 

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1 - yes, i connect min to my router. you will need to go to the network setting on the JVC to read off the IP address

2 - when it was calibrated did the calibrate for HDR? Did they calibrate BT2020 color? If so then the color should be calibrated, you are only adding a new gamma cure with lovingdvd's speed guide. This will not effect any current calibrations, you are just adding new gamma curves to be stored in Custom 1, 2 or 3 gamma slots to be used with HDR.
In the Lovingdvd:s guide, it asks to adjust Brightness and Contrast to optimize the HDR picture. But as far as I can see, those settings are not saved into the new HDR gamma slot, they are placed outside of the gamma slot - I suppose in the Picture Mode memory?
 

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Hi Manni,

I have a question I calibrated HDR10 with Calman and added a 6.8 multiplier Y screen offset. When it was completed I read 118nits with the offset. I check the nits with the offset back to 0 and I read 127 nits.

What is the actual nits reading?

Thanks
Hi there,

You must have entered the offset incorrectly, as the displayed Y should be offset x actual nits.

Are you sure you entered the offset in the Y field, and not in another?

Both nits look like real nits to me, so you haven't used the offset (which means your calibration is likely incorrect).

With real nits of 118nits, the nits with offset should be around 800nits.
 

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Hi there,

You must have entered the offset incorrectly, as the displayed Y should be offset x actual nits.

Are you sure you entered the offset in the Y field, and not in another?

Both nits look like real nits to me, so you haven't used the offset (which means your calibration is likely incorrect).

With real nits of 118nits, the nits with offset should be around 800nits.
Thanks Manni,

Maybe I am not explaining it correctly here is a copy of my calibration report.
and a picture of the the Y setting in Calman.

No Before calibration was done.
 

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Thanks Manni,

Maybe I am not explaining it correctly here is a copy of my calibration report.
and a picture of the the Y setting in Calman.

No Before calibration was done.
You mentioned 118 with offset and 127 nits without offset. That's not possible.

However your calibration seems to have been made with the offset applied correctly, which means a peakY of around 800nits, as I said in my former email.

Looks like you're fine. :)
 

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In the Lovingdvd:s guide, it asks to adjust Brightness and Contrast to optimize the HDR picture. But as far as I can see, those settings are not saved into the new HDR gamma slot, they are placed outside of the gamma slot - I suppose in the Picture Mode memory?

They are saved in the Custom gamma slot. The process in the guide changes what zero is for Contrast and Brightness, so that they are precisely correct when set to zero when using the Custom gamma.
 

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You mentioned 118 with offset and 127 nits without offset. That's not possible.

However your calibration seems to have been made with the offset applied correctly, which means a peakY of around 800nits, as I said in my former email.

Looks like you're fine. :)
Must have been a bad reading or user error as I remember a measuring 127 nits.
However the correct output is 118 nits.
 

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They are saved in the Custom gamma slot. The process in the guide changes what zero is for Contrast and Brightness, so that they are precisely correct when set to zero when using the Custom gamma.
But there are no Contrast and Brightness slides inside the gamma slots, only Picture tone and Dark/Bright level...

I have dedicated the whole day tomorrow to dive into the Arve software and create the custom curve, so hopefully things (and my questions) will fall into place then - because there's some magic here that I don't fully understand. :)

Tonight though, I played around with the standard Gamma D slot and the lens aperture and got a pretty great 4k picture, at least I thought so just comparing to the standard Blu-ray version of the same movie (Sicario and Mad Max) I used the settings in Gamma D that JVC recommended:

Picture tone: 11 (90 inch screen)
Dark level: 5
Bright level: 4

Then the following global settings:

Lamp Power: Low
Lens aperture: 0
Clear Black: Off
Input signal: Standard

Colors, contrast and brightness was left untouched the way they were calibrated by the calibration guy.
 

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Hi i have a x5000 and have setup the bt2020 hdr looks good but just a little bit dark
What can i do to brighten it up do i need a hdfury or something like that ?

Sent from my SM-G955F using Tapatalk
 

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But there are no Contrast and Brightness slides inside the gamma slots, only Picture tone and Dark/Bright level...

I have dedicated the whole day tomorrow to dive into the Arve software and create the custom curve, so hopefully things (and my questions) will fall into place then - because there's some magic here that I don't fully understand. :)

Tonight though, I played around with the standard Gamma D slot and the lens aperture and got a pretty great 4k picture, at least I thought so just comparing to the standard Blu-ray version of the same movie (Sicario and Mad Max) I used the settings in Gamma D that JVC recommended:

Picture tone: 11 (90 inch screen)
Dark level: 5
Bright level: 4

Then the following global settings:

Lamp Power: Low
Lens aperture: 0
Clear Black: Off
Input signal: Standard

Colors, contrast and brightness was left untouched the way they were calibrated by the calibration guy.
Dark level = 5 is what is needed for gamma D, but that raises your black floor and kills your on/off contrast. Fade to black has significantly raised black level with that setting, especially as the DI is disabled with Gamma D. Lowering it to 2 (possibly 3 if you're lucky) doesn't raise the black floor, but crushes black and you lose a significant amount of detail in the low end.

That's the main reason why Gamma D isn't usable and why we need custom curves (or why SDR BT2020 was used before we got custom curves).
 

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Hi i have a x5000 and have setup the bt2020 hdr looks good but just a little bit dark
What can i do to brighten it up do i need a hdfury or something like that ?
Custom or premade gamma curves will fix most of that. Keep in mind though, I've personally found some 4K HDR discs are darker than others and some are darker than their BD counterpart. I've had resistance in mentioning this, but it has been documented and proven by myself and others in various places. The good news is many 4K discs look great and custom gamma will make them even better.

I made two quick start DIY guides to easily and quickly get you started. One that does not require any equipment and one that requires some calibration equipment. Step 3 in that first guide is probably what you are after. You can also look at the bottom of the second guide for some tips on loading premade curves.

Honestly though, doing step 3 in the first guide will take you 30 minutes at most. After you've done it once, repeating it takes less than 5 minutes.
 

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Custom or premade gamma curves will fix most of that. Keep in mind though, I've personally found some 4K HDR discs are darker than others and some are darker than their BD counterpart. I've had resistance in mentioning this, but it has been documented and proven by myself and others in various places. The good news is many 4K discs look great and custom gamma will make them even better.

I made two quick start DIY guides to easily and quickly get you started. One that does not require any equipment and one that requires some calibration equipment. Step 3 in that first guide is probably what you are after. You can also look at the bottom of the second guide for some tips on loading premade curves.

Honestly though, doing step 3 in the first guide will take you 30 minutes at most. After you've done it once, repeating it takes less than 5 minutes.
Thank you very much


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Thank you very much


Sent from my SM-G955F using Tapatalk
If you follow @Dreamliner's guides that he mentioned, it will definitely get you going until you get a grasp on all the great and more indepth info Manni and others have shared;)

BTW, I suggest you use one of Manni's custom gamma curves. I used his "Custom PQ Gamma Manni 190-1000-4000" and it looks great.
 
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Dark level = 5 is what is needed for gamma D, but that raises your black floor and kills your on/off contrast. Fade to black has significantly raised black level with that setting, especially as the DI is disabled with Gamma D. Lowering it to 2 (possibly 3 if you're lucky) doesn't raise the black floor, but crushes black and you lose a significant amount of detail in the low end.

That's the main reason why Gamma D isn't usable and why we need custom curves (or why SDR BT2020 was used before we got custom curves).
Thank you!

I tried creating the custom curve today and came half way - I don't have the Ray test pattern for the Brightness adjustment.

For now and until I have more time, I'm gonna use your latest gamma curve. I have enough light (over 200 nits) so that wont be a problem I believe.

Two questions:

1. I checked with my calibration guy and my JVC is calibrated against Rec 709 only, and they don't do calibration for 4k patterns yet. Will this affect the result in any fundamental way? I know I can do this myself with Autocal and a Spyder but my knowledge here is quite limited.

2. The calibrator says I need to have to projector set to Input level "Super White" in order to get proper gray scale. Is this correct? Isn't Super White for video signals with a 16-255 range only = not standard for most titles?
 
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