CurtPalme.com Home Theater Forum

CasetheCorvetteman · Joined: 09 Nov 2008 Posts: 6326 Location: Australia

Yeah watching 3D movies i didnt care about the scaling.

tanwn · Joined: 26 Dec 2006 Posts: 104

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

ElTopo · Joined: 07 Nov 2006 Posts: 1640

Hey man,

is the Cine9 still up and running.

ElTopo

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

The beauty (CineMax) has been replaced by The Beast Very Happy

I tried to make nice pictures but well, you just have to watch a movie on this one Smile

This is a splitpack with the mainunit on the attick. All cables that end on the neckboards have been replaced. The coax video was soldered on the main board (below). Result was very low noise and perfect gamma.

The unit is positioned as low as possible to have very little keystone correction.

ElTopo · Joined: 07 Nov 2006 Posts: 1640

Have you put all Cine9 boards (incl. fan boards) in the SplitPack ?

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

garyfritz · Joined: 08 Apr 2006 Posts: 12088 Location: Fort Collins, CO

Blue light is bad, no question. But if you are careful to get what is called "warm white" here in the US (2800-3500K or so), they have very low blue emissions:

I also strongly recommend using f.lux (https://justgetflux.com/) to cut way back on blue emissions from your computer/phone after sunset.

I would not worry about too much blue emission from LCD projectors. The bulb may possibly have strong blue emissions (it almost has to, in order to have properly-calibrated D6500 colors), but the projector is only going to transmit the colors it's supposed to.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

I do know that Samsung has some displays they put in retail stores which are blue LED backlit and they're hard to even look at. And they look different to each eye!

I love blue, it's my favorite color, but something about blue LEDs is just NOT what our eyes were meant to see.

Blue LEDs as power indicators? OK. But as part of a light source? I'd rather avoid that.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

Hi some short notes and measurements here. I am still working on the big picture.

This picture is about how our human vision is both scotopic and photopic. Day and night vision for short.

"Years ago it was thought that the cones were responsible for daytime vision and rods for nighttime vision. Because of this, light meters that measure lighting levels such as footcandles, lumens, lux, etc. are weighted to the cone activated part of the eye ignoring the effect of rod-activated vision. But according to a study by Dr. Sam Berman and Dr. Don Jewett the roles of rods and cones are not exclusive but actually share responsibility depending on lighting conditions. Their experiments, sponsored by the US Dept. of Energy, show that rods do play a role in typical workplace lighting conditions. Thus the devices we use to measure light are not consistent with our human perception of lighting conditions. This has led to a movement among some lighting professionals to modify our criteria to include for rod sensitivity."
http://www.jacomb.net/pdf/photopic_scotopic.pdf

Now to get photopic white the blue led is far more stimulating the scotopic region than sunlight does with a normal spectrum blue. This results in wider pupils (less sharp vision), sleeping problems and possible eye damage on frequent exposure.

Is this a hazard? There is a body of evidence that young and old people are at danger. Animal studies show simple blindness after long exposure of these animals.
people also sleep worse because this scotopic region also regulates sleep.
Recent alarming messages from optician are that they have to put glasses on young people much more often. What will be in the papers in 20 years from now?

My personal experience with a qled Sony uhd (samsung has these now) it made my eyes very tired and I could not watch more than one hour a day or so. With my kuro/crt I can watch much longer before getting tired.

But it is not just your television. It is also you lightning, ipad your phone your computer and they are even replacing street lightning with led.

Now just for fun I did some measurements with my i1pro spectrometer.

The first is a fullspectrum light
The second is a white led
The third is a warm white led (the spectrum Gary presented but this one is real, still some blue Smile

)
The fourth is a candescent light and the fifth a carbon wire lamp.

Now the final picture, this is a CRT. The blue light is not showing any dips so the blue you see with your photopic vison is the blue you get with your scotopic vision just like daylight Very Happy

garyfritz · Joined: 08 Apr 2006 Posts: 12088 Location: Fort Collins, CO

Fascinating stuff! I never believed the idea of a day/night "switch" between rods and cones. We didn't evolve only in full daylight and full dark. It only makes sense that there would be a transitional region where both mechanisms are in play.

But I've never heard of the photopic / scotopic perceptions. I'm confused by the concern about blue light stimulating the scotopic vision more than sunlight. There is a lot of blue-light energy in sunlight. I assume the rods are not "shuttered" during the day, so they're getting massive amounts of blue-light energy. Why would a blue LED projector or even a blue-emitting phone/pad screen cause more damage than the blue energy of the massively-brighter sun?

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

It never made sense to me that the parts of the eye that work in the dark stop working when there's plenty of light.

I always questioned that once I stopped to think about it.

El Duderino · Joined: 23 Jan 2011 Posts: 4653 Location: Portland, OR

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

ElTopo · Joined: 07 Nov 2006 Posts: 1640

Is it possible to have the same fan curcuit chain inside the 909 Split Pack ?

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

ElTopo · Joined: 07 Nov 2006 Posts: 1640

Well it should only put the two boards from the Cine9 into the SplitPack and also the Cine9 controller.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

dummyload · Joined: 06 Apr 2006 Posts: 38 Location: belgium

And I think it is best to reverse mounting the fan in front of the focus board ,it has to blow air towards the focus board in order to make this extra fan board work correctly temperature wise , because al trays I have seen with this fan board installed have the focus fan reversed .

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

The spectral distribution of blue is very important for potential eye damage, good sleep and my guess is that it is also important for good dark scenes. What you need is blue light from 460nm to 490nm. That is the positive blue. Blue of 440nm is potential damaging.

Especially kids I advise to limit the amount of time with blue light because because only after 16 years eyes develop some protection against these blue frequencies.

"One of the world’s leading opticians, Specsavers, has noticed a worrying trend in increasing eye problems, particularly myopia (short-sightedness), in children and are advising parents to limit screen time, make sure that kids get plenty of time outside..."
http://www.theleader.info/2017/09/01/increasing-eye-problems-children-observed-optical-group/#_

Here the spectral distribution of my CRT splitpack that I recorded myself. Notice the blue at the right frequencies of 460nm till 490nm.

CRT nice broad blue Smile

UHP lamp from a digital JVC HD350 somewhat less nice, but still... Sad

Spectrum distribution of the Samsung D7000 led television. Notice the damaging frequencies and the lack of good blue. Tiresome blue and potential damaging. Notice the higher intensity because it is a television. Look at the relative intensity of blue.

Xenon lamp of a Sony VW100 digital. Very nice lamp!