CurtPalme.com Home Theater Forum

kschmit2 · Posted: Mon Jan 19, 2009 9:29 am Post subject:

ohh, and here's a screenshot of my AVSforumTestPic I took in late May 2008:

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

So 1080i/96 is the same bandwidth as 1080p/48? I would never have thought that would display on a PG+...Does it make the projector run hotter?

kschmit2 · Posted: Mon Jan 19, 2009 6:45 pm Post subject:

Yes, same bandwidth and scanrate.

Scan rate is just 59.7 kHz, and the PJ does not run hotter at all (at least in my case). My PJ is not in a hushbox, and I use a Sony PSS-10 to have it lowered about 10" from the ceiling so that there is enough clearance for hot air just flow away.
I have also minimally modified the 2 fans on the bottom of the PJ using Noisemagic NMT-2 thermo controllers on the stock fans. More info here: http://www.noisemagic.de/info/nmt-2/info.htm#english and here: http://www.noisemagic.de/pdf/thermocontrol/nmt-2/ver2/an_loet_de-eng_screen.pdf
These controllers will spin up the fans at 12V, and will already run at full speed once the temps reach 50°C.

My exhaust temps are much lower though. Usually just slightly above ambient temperature.

Kai

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

How do these things control fan noise? I don't get it...

kschmit2 · Posted: Mon Jan 19, 2009 7:18 pm Post subject:

It makes the fans run at lower voltage as long as temps are below 50°C.

The 12V I mentioned is just during spin-up to ensure that the fan starts. It then drops the voltage, and raises it again as temperature increases.

It's not much of a difference, and definitely not a must-have item. I just happened to have a couple of them around Smile

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

I see...when I had an NEC, I installed a manual switch which lowered fan voltage. This was with a PGXtra...and was definitely required!

km987654 · Posted: Wed Jan 21, 2009 9:28 am Post subject:

Its just great to see people hooked on a "hobby" prepared to experiment and produce fantastic results!!!!

Jesse S · Joined: 12 May 2007 Posts: 209 Location: Etobicoke

I setup 1080i 96hz today on my XGLC1352.

Impressions-

I can see scanlines even at 10' away, and I wasn't even wearing my glasses (light astigmatism). That takes away from
the film-like appearance.

Motion seems blurred, more so than 720p setups. In motion, 1080i is more like 540p as the frames never complete drawing
before the scene changes.

Good detail and depth on static shots. The problem is that movies usually have some motion.

I could defocus the green and red a little (electronically) to help the scanlines blend together.

I'm going to have to swap back and forth to 720p to see if it has more resolution in motion. This problem is similar to LCD tv's
that drop from 1080p static to 330-660 lines in motion (depending on model).

Mark_A_W · Posted: Wed Jan 21, 2009 11:54 pm Post subject:

If you have huge scanlines, change your position adjustment from WIDE to NARROW.

I think it is in INFO menu, not certain.

I had an issue with one interlaced res when it wasn't syncing properly, and this helped.

The scanlines (fieldlines really) for 1080i 96hz on my system are no worse than 1920x804p at 72hz. They basically look identical, apart from the aspect ratio.

Jesse S · Joined: 12 May 2007 Posts: 209 Location: Etobicoke

The scanlines are visible because 1080i is just very easy to resolve. Even my 6PG had visible scanlines at 1080i. I'll try the setting though.

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

even your 6pg can't resolve 1080 lines...I don't know what you're talking about here. I looked at 1080i 96 and indeed, it looks like 1080p to me. But I'll try 720P/48 and see how that looks ( I used to love this res as I liked the flicker)

Mark_A_W · Posted: Thu Jan 22, 2009 4:12 am Post subject:

Jesse S · Joined: 12 May 2007 Posts: 209 Location: Etobicoke

Tried narrow, was on wide. Same image. For 540p I'm referring to the apparent resolution with motion, nothing to do with the source.

I've seen countless times where people say that 1080i and 1080p are indistinguishable and that is absolutely false. I've seen 1080p on a G90 and a Marquee 9500 and it looks nothing like 1080i. I'm not convinced of this 1080i@96hz idea yet. It has as many drawbacks as benefits.

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

I saw 1080i on a Marquee...when then switched it to 1080p...and 1080p was slightly better. Certainly not twice the bandwidth worth of improvement.

radar · Joined: 05 Dec 2007 Posts: 72 Location: Sydney, Australia

Hi,

"ohh, and here's a screenshot of my AVSforumTestPic I took..."

Do you have an exact web address for that test pic? I couldn't find it.

Thanks,
Kevin.

kschmit2 · Posted: Fri Jan 23, 2009 12:31 pm Post subject:

amt_austin · Joined: 23 Jan 2008 Posts: 38 Location: Austin, TX,

VideoGrabber · Joined: 09 Apr 2006 Posts: 933 Location: Michigan

Austin inquired:
> How is this even mathematically possible? <

It's not... for precisely the reasons you mentioned. Jesse's concerns only come into play on video-sourced material, not film. With video, vertical pans on 1080i material can devolve into an effective 540p vertical resolution, as he points out. However, this has already happened, at the point of capture, and is unaffected by later displaying it at 1080i or 1080p. I.e., the extra vertical rez is already gone.

Now if the original source was captured at 1080p (or 720p), then rendering it at 1080i could expose the kind of vertical loss that Jesse described. So the number of situations where this could be an issue are fairly limited.

However, when someone reports they're seeing something, as Jesse has, I tend to believe them, even if I can't immediately explain it. If he's not using 24p sources, or performing IVTC correctly to extract that rate from film material, he could observe the same effect, even with movies. Or possibly if he's not frame-locked, he could be essentially dropping fields, with a resultant blurring. He'd have to describe his scenario in more detail, to be sure.

Jesse S · Joined: 12 May 2007 Posts: 209 Location: Etobicoke

My source is all x264 at 1080p 24fps. I haven't had a chance to compare 720p 72hz to this 1080i 96hz. But, I'm seeing a lot more blurring in motion than what I'm used to with 720p 72hz (videocard setup not source resolution).

Jesse S · Joined: 12 May 2007 Posts: 209 Location: Etobicoke

I flipped back and forth from 1280x720p 72hz and 1920x1080i 96hz.

The scan lines drive me nuts on 1080i. I can see them anywhere onscreen that is medium to fully lit. It's much finer than the 480i that you'd get from hooking up a dvd player to s-video, but it is very apparent even at 10' away. I saw the same thing 5 years back when I had the Rogers HD cable box, which output 1080i 60hz and that was on my 6PG. Lettering in movies has scan lines and artifacts from the interlacing. It seems like there is more detail on 1080p source but the artifacts and scan lines negate much of the benefit.

I thought about defocusing electronically and that won't work either. It might blend the lines vertically but then you are blurring adjacent pixels. You would have to create oval dots using the astig controls.

Perhaps 1920x1440i?