The Sammy uses BT.2020 colour and St.2084 gamma for HDR and Rec.709 colour St.1886 gamma for SDR - so with the HDR > SDR we're in Rec.706 colour space and BT.1886 power law gamma - ie standard 2.2 gamma - basically that's how it should be and the X9S does a decent job of converting BT.2020 colour to Rec.709 colour and ST.2084 gamma to ST.1886 gamma (wow! far too many numbers!!!) I really feel for you because I went through exactly the same pain trying to make 4K UHD HDR rips look as good as my 2K standard bluray rips. I found my solution in designing my own PQ (ish) gamma curve and using an HDFury Vertex to control the Edid but your situation is different since your PJ only takes in Rec.709 and SDR - but... it's a hell of a projector, so it's worth some effort to give it what it wants! And glad to help out - I love this stuff, particularly when it gets tricky
I have a x9s and a projector Epson tw7300 with hdr, I use hdr to sdr function, but you suggest to set bt2020 on my projector or keep auto?
Definitely Rec.709 if you can select that or otherwise auto - I'm not familiar with that PJ but in HDR>SDR the X9S will output Rec.709 colour, definitely not BT.2020.
Wow, I don't think I'd really be able to go that far... I admit I'm way too lazy. I've checked the price for that HDFury Vertex beast... yikes! Of course I wouldn't even know what to do with that kind of control on the gamma and all the other expert settings, so... I really hope I get decent quality with a few tweaks and I'll just leave it like that. But you're right, it's a real pain: you think you're ready to make the jump to 4K, and suddenly you find out they've created new hurdles you've never heard about... and you feel the need to upgrade your system. I'd just be happy to have those old 2K bluray colors and 4K resolution!
HDR is always tone mapped to be displayed, it just depends what does the tone mapping - the source or the display. With an HDR monitor, the monitor would generally do it and the level to which a tone map is applied is dependent on the display's luminance capabilities but with an SDR monitor, the source must do it, and it must be very aggressive and map into a standard power gamma. But if you can retain the BT.2020 colour space, you're keeping the wide 10-bit colour gamut so although the luminance doesn't have the same resolution, ie gradations, the colour does. The biggest mistake people make in regards to HDR and WCG is to think that HDR should be brighter and a WCG should be more "colourful" - they shouldn't - the average picture level for an HDR grade should be very similar to that of the SDR grade, the only difference being in the specular highlights, and WCG is not more colourful, there are just more gradations between the colours. Black is still black, white is still white, red is still red etc... This link may explain better: https://www.lightillusion.com/uhdtv.html
Yes indeed - If your projector will not handle HDR correctly but it will accept BT.2020, then yes, SDR.2020 is very useful and a better option than simple HDR to SDR. You have to make sure you can choose BT.2020 colour AND a standard gamma at the same time - I see no reason why not, it'd be mad if you couldn't, but it's worth checking.
I sent an email to Zidoo about this and pointed them to this thread - just got a reply that they're passing it to the engineers and will revert to me, so let's see what happens... With any luck they'll be able to revert to the old HDR to SDR mechanism used on the X9S.
I can try this evening, thank you.. Someone wants to make an exchange..?My x9s and some money for a z9s..?..?
Thanks Markswift, I was about to mail them but you beat me to it! That's really good news, I just hope they solve it and release a new update before I have to give back my Z9S to Amazon (wishful thinking...)
I managed to select on my projector BT 2020 and Gamma (+2 +1 0 -1 -2)a selecting hdr to sdr on zidoo.It appears a little saturated but struggling with all pictures settings I've managed to reach interesting results.Surely with a professional device you can have better tone mapping, but for now it's enough for me.
The thing is, if you're using HDR>SDR on your X9S, you're now taking the source in BT.2020 space, converting (effectively compressing) it down into the smaller Rec.709 space in the X9S and then you're taking that already converted Rec.709 image and placing it back in the large Bt.2020 colour space in the projector without any conversion. In order to use HDR>SDR your projector should be in Rec.709 colour (because that's what the X9S is spitting out) and a gamma of 2.2 or possibly 2.0. You should only use BT.2020 with either HDR or HDR>SDR.2020 (Z9S only) because those are the only two cases where the Zidoos will output in BT.2020 space. I'm not sure how the Epson's gamma settings of +2 +1 0 -1 -2 relate to standard power gammas, but I would expect it to be as follows: +2 = 2.4 +1 = 2.3 0 = 2.2 -1 = 2.1 -2 = 2.0 But that's only an educated guess, although I can't see why it would be done any other way. There is a possibility the + & - are switched, eg +2 may equal 2.0 since reducing gamma effectively increases picture level so Epson may have implemented it like that so you see the picture going brighter as you "increase" the gamma... You'll have to play with it and see. However, I would say the best starting point using HDR>SDR in the X9S is Rec.709, gamma "0" in the projector and adjust gamma which ever way is correct if it's too dark.
At the moment i've chosen Gamma - 2 and Natural color mode and I see the movie as it would be SDR at all.But if I choose Cinema color mode automatically starts DCI P3 color gamma not well mapped I think, in fact I see better with Natural color mode. The conbination I created with BT 2020 is a little over saturated, but you have the idea of what makes HDR. I think the better solution for me is to find a good player with HDR to SDR BT 2020, maybe the z9s for not paying too much.
I think so too - As far as I know the only dedicated media player about at the moment that does SDR.2020 is the Z9S. It also happens to be one of the cheapest, and in my very biased (but fussy!) opinion, the best.
Those were photos of a 2018 projector which is not HDR compatible. It is also not HDCP2.2 compatible. The 60Hz is enabled with the bluray player Sony x800.
That would explain why it looks exactly like HDR looks like when pushed into Rec.709 at ST.2084 Switch to HDR to SDR and you'll see a great improvement.. Presumably the BluRay player will have an auto framerate setting to play sources back at the correct framerate?
Thanks to your posts I tried a different thing..I kept Hdr source and put Gamma to +2 (for some 4k movies +1 is enough) on the projector and now problems of lack of luminance are almost gone, no more hdr to sdr
Here's my update on the problem: I've bought the X9S, and the HDR to SDR conversion works. It outputs a very contrasted image, I had to work on the brightness/contrast settings, but it's pretty decent. However, I still have my Z9S, and I really hope they'll fix this problem on the next firmware release! I mean, how difficult can it be, if it works on the X9S? I really like the new remote and the overall performance of the Z9S. So, please take note of this Zidoo guys and fix it! As a guy who bought not one, but TWO of your products (one of the two will go to my brother's house) I think I deserve a bit of love... and I can't be the only guy in the world with a rec.709 4K display that wants to use your player, right?
Very helpful post showing the Z9S vs X9S. I need a new player this will help me decide, any update if they fixed Z9S?
