JVC RS4500 (native 4K laser projector)

[Woof Woof]

This thread suddenly seemed very inactive.

Are all the owners playing with their units?

BTW Kris mentioned a new way of calibrating the HDR modes.

Does that use the auto calibration function of the Z1/RS4500?

What other gear do I need to run the auto calibration.

[AVSCraig]

This thread suddenly seemed very inactive.

Are all the owners playing with their units?

BTW Kris mentioned a new way of calibrating the HDR modes.

Does that use the auto calibration function of the Z1/RS4500?

What other gear do I need to run the auto calibration.

I actually was not able to play with mine until last night. What Kris is referring to are Manni's custom HDR gammas. I'm assuming that you download them the same way as loading BT.2020 into my RS600.

I'm going to verify that with JVC !

[AVSCraig]

I used my new Sper Scientific light meter to re - measure my RS4500. Mind you that these numbers only apply to my setup and should be taken with a grain of salt. If I moved 8" closer to the projector, the numbers jump and I would have much higher numbers. This is mostly so I'll have an idea how bright I'm watching in MY room on MY screen with MY setup. Taken at the screen ( 122" 16:9 Stewart Cima Neve - 1.1 gain ), facing the projector from 14' , Natural mode, manual iris open, auto iris off  -

Low laser - 615.64 lumens. That would give me 15 + foot lamberts.

Mid Laser - 1516.69 lumens. That would give me 38 foot lamberts !

High Laser - 2242.42 lumens. That would give me 56.22 foot lamberts - ha !

The way I've been watching it - Natural mode,  Mid Laser, manual iris at -7, laser dimming mode 2 - 1104.90 lumens, 27.70 foot lamberts ! No wonder I thought it was bright !

[mark_h]

I've noticed a few times while watching films that I am being lit up by light, eg I can see light on my hands, even though I am not obstructing the projector image in any way.  Putting a piece of card up against the projector shows a wide circle of light being thrown way outside the radius of the image itself.  So it's stray light from the lens that is lighting me up.  This is most noticeable when the on-screen image is dark and my eyes are aclimatised to the darkness. This stray light could very well be raising the black floor/lowering contrast.  I will measure tomorrow with my Klein K10A.  If it can be measured that the black floor is being lifted, I will experiment with making some sort mask that can sit in front of the projector to stop it throwing the stray light.

Never noticed this on my Sony 1000.

Anybody else spotted this?  Is it a JVC "thing"?

[Pultzar]

I've noticed a few times while watching films that I am being lit up by light, eg I can see light on my hands, even though I am not obstructing the projector image in any way.  Putting a piece of card up against the projector shows a wide circle of light being thrown way outside the radius of the image itself.  So it's stray light from the lens that is lighting me up.  This is most noticeable when the on-screen image is dark and my eyes are aclimatised to the darkness. This stray light could very well be raising the black floor/lowering contrast.  I will measure tomorrow with my Klein K10A.  If it can be measured that the black floor is being lifted, I will experiment with making some sort mask that can sit in front of the projector to stop it throwing the stray light.

Never noticed this on my Sony 1000.

Anybody else spotted this?  Is it a JVC "thing"?

My RS1 also has stray light.  One one point I put a black velvet card along the bottom of the lens to block this.

[AVSCraig]

I've noticed a few times while watching films that I am being lit up by light, eg I can see light on my hands, even though I am not obstructing the projector image in any way.  Putting a piece of card up against the projector shows a wide circle of light being thrown way outside the radius of the image itself.  So it's stray light from the lens that is lighting me up.  This is most noticeable when the on-screen image is dark and my eyes are aclimatised to the darkness. This stray light could very well be raising the black floor/lowering contrast.  I will measure tomorrow with my Klein K10A.  If it can be measured that the black floor is being lifted, I will experiment with making some sort mask that can sit in front of the projector to stop it throwing the stray light.

Never noticed this on my Sony 1000.

Anybody else spotted this?  Is it a JVC "thing"?

I haven't seen that. It's coming from inside the lens ? It would have to - my lens has black material around it.

[lygren]

I used my new Sper Scientific light meter to re - measure my RS4500. Mind you that these numbers only apply to my setup and should be taken with a grain of salt. If I moved 8" closer to the projector, the numbers jump and I would have much higher numbers. This is mostly so I'll have an idea how bright I'm watching in MY room on MY screen with MY setup. Taken at the screen ( 122" 16:9 Stewart Cima Neve - 1.1 gain ), facing the projector from 14' , Natural mode, manual iris open, auto iris off  -

Low laser - 615.64 lumens. That would give me 15 + foot lamberts.

Mid Laser - 1516.69 lumens. That would give me 38 foot lamberts !

High Laser - 2242.42 lumens. That would give me 56.22 foot lamberts - ha !

The way I've been watching it - Natural mode,  Mid Laser, manual iris at -7, laser dimming mode 2 - 1104.90 lumens, 27.70 foot lamberts ! No wonder I thought it was bright !

Just returned from ISE where we measured 40 fl on our 12 feet screen using a Barco prototype Loki (4K 8K lumen phosphor laser) and I honestly have to say; the more the merrier!! This DLPs features about 500:1 ANSI though, resulting in very impressive intra-scene contrast in scenes where you have a typical mix of bright / black sections, although black levels is quite poor on the typical scenes where most of the objects are dark... Still, I´d happily sacrifice some contrast to obtain those dynamics, simply breathtaking when content calls for it. Back to the 13 feet screen and Z1 at my showroom, the blacks are certainly far better, but I do have to admit I miss the extreme light output of the Barco. There´s definately potential in projection still ahead, that´s a good thing at least! As for the Z1, reducing the screen size to move towards 30-40 fl I´m quite confident it´ll look even more impressive...!

[mark_h]

I haven't seen that. It's coming from inside the lens ? It would have to - my lens has black material around it.

It's coming from/through the lens.  Just hold a piece of cardboard in front of the lens and you will see the wide spill halo around the main image.  I'm about to head into my room and see if I can measure anything from the spill, ie whether it is raising the black floor. 

[mark_h]

Couldn't measure any black level change off the screen (perhaps a benefit of a non-reflective black pit), but did notice myself being lit up again during the film, so have crafted a bit of card covered in velvet to block the light spill.

It's easiest to see the spill when the projector is displaying a black field.  You can then move your hands around the non-screen region and see them light up as they enter the sphere of light spill.  During darker scenes in movies I became aware of the same, as well as my clothes being lit too, which is a distraction.

Will be interesting to watch the next movie with the spill barrier in place.

[mark_h]

Still being blown away by this projector, especially with UHD discs.  My "too large" screen really allows one to see all the extra resolution of the 4K discs

[mark_h]

Watched another film this afternoon with the light spill "filter" in place.  Much better.  Instead of being lit up, I am once again sat in total darkness without distraction.

[lygren]

Couldn't measure any black level change off the screen (perhaps a benefit of a non-reflective black pit), but did notice myself being lit up again during the film, so have crafted a bit of card covered in velvet to block the light spill.

It's easiest to see the spill when the projector is displaying a black field.  You can then move your hands around the non-screen region and see them light up as they enter the sphere of light spill.  During darker scenes in movies I became aware of the same, as well as my clothes being lit too, which is a distraction.

Will be interesting to watch the next movie with the spill barrier in place.

That "Halo" is there on the RS/X-series as well and it would probably be a very good idea to get rid of it! Wanna upload a pic of your custom made "light spill voider"??

[AVSCraig]

That "Halo" is there on the RS/X-series as well and it would probably be a very good idea to get rid of it! Wanna upload a pic of your custom made "light spill voider"??

Interesting - I never noticed that.

[lygren]

Interesting - I never noticed that.

Well, to be more spesific, I´ve only had a RS400 and a couple of X5000s at my private cinema (I replace them quite often, I like´em "young´n fresh"... ), where I noticed these halos, never did look for or notice it specifically at the RS600 running on my showroom though, so in theory it might not be there on RS500/600...

[mark_h]

That "Halo" is there on the RS/X-series as well and it would probably be a very good idea to get rid of it! Wanna upload a pic of your custom made "light spill voider"??

The filter is just a bit of card with a 16:9 hole cut in it   Covered it in black velvet, to match the hush box, and to avoid reflections backwards to the projector, and stapled it to the front of the box so that the hangs down in front of the lens without obstructing the vents.  Cheapest upgrade to my room yet!