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I wouldn't at this stage in the game bother with the marginal up from 520 to 990. 990 Used the newer eshift algo which some say robs sharpness, so what you gain in lens you might not keep, plus you have a 520 you know and understand vs an unknown qty with no warranty.
Save your money for next rev of non-eshift when they've put to bed the teething issues.
Yes I had the same thought: better lens but not such a ‘better’ sharpness due to the ‘softer’ e-shift 5 according to many many comparisons with the 4. And yes to leave something that I know in perfect conditions for something I have no knowledge about is highly risky. I am tempted by a 620 whose owner asks basically the same price I was asked for the 990. The 620 is a more ‘stable’ model but I feel unsure about the ‘upgrade’ or which would be a ‘better’ upgrade between a 620 and a 990 equally priced. Thank you very much for your kindness
 

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Read the reviews about the NX5 and what you may give up in Black Level. I'd go for the 990, but what is the return policy? Perhaps some of the 990 owners on this forum can give you some simple "tests" to run on the 990 if you get it. FWIW, I own the 790 and have not had any problems with D.I., lens shift, etc. (knock on wood!!!). Yes, stay safe!
There are many owners who complained a lot about DI issues with 790 and I am learning now with the 990 as well. I think I am still oriented towards a e-shift models, although the NX5 beside a lack in black levels (if only compared to the JVCs!) is for sure a good improvement as to HDR performance. Thank you very much!
 

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Hello, new owner of a (preowned/uncalibrated) RS540 here - about to start the calibration exercise and have a couple of basic questions. (Unable to find any local calibrators available, I decided to give the DIY route a go.) Not sure this is the right place to post vs one of the cal discussions but thought I'd start here.... I have gone through many of the earlier/related calibration threads but am still a bit unclear on a couple of basics.

1) I've measured my lighting with a handheld light meter, and if my math is right I'm getting ~18ft--L for SDR (low lamp, manual aperture=0) in my near bat-cave like room w/ST130 screen. Now what do I do with this information (besides noting it to check for future lamp degradation)? ... e.g. do I dial back the aperture until I get down to the ISF recommendation of ~12ft-L to realize darker blacks? Or is it just informational at this point.

2) For the JVC Autocal (I will be using a Spyder5 express), do turn off the "Screen adjust" parameter before running the calibration? If so, do I then set the screen adjust to my given screen type after calibration, or do I leave it off as calibration takes care of this. Since the Spyder5 gets pointed at the PJ, I think adding the adjustment AFTER the cal makes sense, but I'm not sure if I should disable it beforehand or not.

thanks
 

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Hello, new owner of a (preowned/uncalibrated) RS540 here - about to start the calibration exercise and have a couple of basic questions. (Unable to find any local calibrators available, I decided to give the DIY route a go.) Not sure this is the right place to post vs one of the cal discussions but thought I'd start here.... I have gone through many of the earlier/related calibration threads but am still a bit unclear on a couple of basics.

1) I've measured my lighting with a handheld light meter, and if my math is right I'm getting ~18ft--L for SDR (low lamp, manual aperture=0) in my near bat-cave like room w/ST130 screen. Now what do I do with this information (besides noting it to check for future lamp degradation)? ... e.g. do I dial back the aperture until I get down to the ISF recommendation of ~12ft-L to realize darker blacks? Or is it just informational at this point.

2) For the JVC Autocal (I will be using a Spyder5 express), do turn off the "Screen adjust" parameter before running the calibration? If so, do I then set the screen adjust to my given screen type after calibration, or do I leave it off as calibration takes care of this. Since the Spyder5 gets pointed at the PJ, I think adding the adjustment AFTER the cal makes sense, but I'm not sure if I should disable it beforehand or not.

thanks
1) I believe the recommended brightness is 16-22 ftL for a dark theatre. I use 19ftL (if my measurements using Spyder5 are correct) and wouldn't be happy with anything lower, but I'm not in a bat cave. Just set the brightness to a comfortable level. That's a luxus of a home theatre - do whatever you like and be happy.
It would be good however if you can use an iris setting lower than 0 (if you like the picture of course). That way you would have some room to compensate for the lamp degradation in the future.

2) I would disable screen type during calibration as well. As you pointed out that makes total sense when measuring from the lens.

Btw, how big is your screen and how many hours are on the lamp?
 

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Btw, how big is your screen and how many hours are on the lamp?
My screen is a modest 94" , with seating location 10.5' back. The PJ has 950hrs on the bulb.

I think on my prior PJ (a x500r) I had the aperture around -7, but I forgot to check that before taking it down:rolleyes:. Not that it would be an apples to apples reference. With this one I'm finding -7ish to be fine for film but a bit dark for sports. I'm trending towards a compromise around -3 to -5 range. This is all after running the auto-cal. Have yet to try load any custom curves, which I take it have more value on HDR. All the related cal info out there is somewhat overwhelming, so my plan is to settle on my SDR settings first then move to HDR.
 

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My screen is a modest 94" , with seating location 10.5' back. The PJ has 950hrs on the bulb.

I think on my prior PJ (a x500r) I had the aperture around -7, but I forgot to check that before taking it down:rolleyes:. Not that it would be an apples to apples reference. With this one I'm finding -7ish to be fine for film but a bit dark for sports. I'm trending towards a compromise around -3 to -5 range. This is all after running the auto-cal. Have yet to try load any custom curves, which I take it have more value on HDR. All the related cal info out there is somewhat overwhelming, so my plan is to settle on my SDR settings first then move to HDR.
Depending on your screen material you may be getting quite the output with that size screen. I get about 15 ftL on a 100" screen with 1.1. gain at -10. More than enough for my bat cave.

Yes, custom curves are for HDR only.
 

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Quick question about 4k HDR handling.

Is it possible to send 1080p signal with wide color gamut to our JVC without triggering it to enable e-shift? What is the trigger for 4k profile (and e-shift with it) to get enabled in our JVCs?

I am considering doing 4k to 1080p downscaling in MadVR while doing Dynamic Tone Mapping and retaining wide colour gamut, but I would like to stay in 1080 without e-shift as it would not be needed.

The reasons is that I would imagine MadVR will do better job down scaling than JVC because I assume JVC has to downscale 4k to 1080p?

Another questions is am I right that if I use MadVR tone mapping I do not need custom curves uploading to JVC? And if I would do 3D lut calibration then for sure I do not need custom curves?

Thanks
 

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Another questions is am I right that if I use MadVR tone mapping I do not need custom curves uploading to JVC? And if I would do 3D lut calibration then for sure I do not need custom curves?
I'll just answer this question as I'm not knowledgable enough to address the rest.

You do not need to upload custom HDR curves when using the tone mapping from madVR.
madVR is sending an SDR signal based on a 2.4 gamma, keeping 10bit colors from the HDR source.
What differs SDR from HDR in terms of colors is bit depth and color gamut, BT.709 vs. BT.2020.
BT.709 uses 8bit colors, while BT.2020 uses 10bit colors for HDR10, 12bit for Dolby Vision.
10bit colors can be sent through an SDR-signal, not requiring custom HDR curves in the JVC.

3D LUT has nothing to do with custom HDR curves, nor is it HDR or SDR specific.
3D LUT is a three-dimensional way of looking at colors, calibrating in the very same way.
3D LUT is a more advanced compared to manual calibration, as it is based on algorithms.
It calculates where your display device current is in terms of accuracy, calculates an offset, and adjusts.

Custom HDR curves has nothing to do with colors, they are just modified gamma curves for HDR.
Gamma is separate from colors in calibration, and a 3D LUT calibration does not address your gamma.
You can take any 3D LUT and just alter/modify the gamma for 3D LUT's with different gammas.
Colors are one thing, gamma is another, think of gamma as brightness, colors are just colors.
 

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Quick question about 4k HDR handling.

Is it possible to send 1080p signal with wide color gamut to our JVC without triggering it to enable e-shift? What is the trigger for 4k profile (and e-shift with it) to get enabled in our JVCs?

I am considering doing 4k to 1080p downscaling in MadVR while doing Dynamic Tone Mapping and retaining wide colour gamut, but I would like to stay in 1080 without e-shift as it would not be needed.

The reasons is that I would imagine MadVR will do better job down scaling than JVC because I assume JVC has to downscale 4k to 1080p?

Another questions is am I right that if I use MadVR tone mapping I do not need custom curves uploading to JVC? And if I would do 3D lut calibration then for sure I do not need custom curves?

Thanks
You can turn off e-shift when it receives 1080p.
 

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Quick question about 4k HDR handling.

Is it possible to send 1080p signal with wide color gamut to our JVC without triggering it to enable e-shift? What is the trigger for 4k profile (and e-shift with it) to get enabled in our JVCs?

I am considering doing 4k to 1080p downscaling in MadVR while doing Dynamic Tone Mapping and retaining wide colour gamut, but I would like to stay in 1080 without e-shift as it would not be needed.

The reasons is that I would imagine MadVR will do better job down scaling than JVC because I assume JVC has to downscale 4k to 1080p?

Another questions is am I right that if I use MadVR tone mapping I do not need custom curves uploading to JVC? And if I would do 3D lut calibration then for sure I do not need custom curves?

Thanks
4K and HDR are independent things. There is no 4K profile but there is a HDR one. It is activated if HDR flag is present in the signal. E-shift is activated if resolution is 4K (regardless of SDR or HDR).

Although e-shift gives only half of the resolution of native 4K, it is still the double of 1080p. The e-shift mode should give more detail on 4K material than downscaling in player to 1080p. At least that's what e-shift was developed for. The tests also show higher resolution with e-shift on 4K signal than 1080p.
 

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A follow-on question regarding my new/used RS540 and my newbie light measurement results.

Post auto-cal, I get a peak reading of 160 lux / 390 lumens / 19.3 ft-L, with the peak being at the center of my 94" ST130 (1.3 gain) screen using "natural" mode, standard color profile (not "high bright"), low lamp mode with IRIS fully open (LA=0). The throw distance is 19'. Meter was facing the lens (not screen).

I am using this cheap meter: https://www.amazon.com/gp/product/B00992B29I/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

The light levels seem a bit low vs what I have seen others report, and if I plug all the same data into the calculator at webprojectorcalculator.com, for this model and bulb age it suggests I should get ~500 lumens / 24 ft-L in calibrated low lamp mode.

So I am wondering whether I might have a poor performing bulb that would be worth replacing, or just chalk it up to a 20% meter error (which seems high but I have no basis for judgment of that beyond their 5% claim).

I have concluded I want to crank the aperture down to at least -5 for black levels (still early in my setup process), which brings me down to ~13 ft-L and looks a bit too dim to me but I could live with it.

Guess I'm mainly looking for feedback on whether this is an unusually low light level or within normal performance given the other parameters... thanks!
 
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