CurtPalme.com Home Theater Forum

[mhalsan]

Hi everyone!

I've been reading around on this site, both the forums and the setup tips/manuals. Curt mentiones several times that the manufacturer's rated maximum resolution (2500x2000 for the higher end) might be higher than what can actually be displayed. I realize that a lot of this has to do with the set's video bandwidth, signal source, refresh rate, CRT spot size, optical setup, convergence, etc.

I'd like to know some opinions on what's practical for high-res computer graphics, which is somewhat more demanding than video or even 1080p. Assuming one of the high end models with a DVI input (9500LC Ultra) and a lot of patience in setup, what's reasonable to expect?

2560x1600 (through DVI) is readily supported by modern video cards, but you could always set up a custom resolution with fewer pixels...........

Thanks, mhalsan

[WanMan]

Trying to get the spot sharp and small enough to create a useful high-resolution image is difficult. Just because it can accept and display a resolution doesn't mean its sharp--or otherwise worth a dang.

[mhalsan]

How much improvement will the mods make- like the higher resolution CRTs, and Mike Parker's neck boards?
I'm open to suggestions- I'm upgrading from my Toshiba this winter and I'd like to make sure I make a good decision.

Most of this forum deals with hi-def video sources, so----- with a good video card set to 1920x1080 resolution, will a CRT or a digital projector look better for graphics & data? (with careful, detailed setup on one of the higher-end models)


Thanks, mhalsan

[Spanky Ham]

Scott could probably answer this better than most, since he has to work with high resolutions. I would guess 1920x1440 would be easily achieved.

[r.bauer]

[mhalsan]

OK, so on DVI Single link / HDMI we're limited to about 165MHz pixel clock. (This number from the information on Moome's HDMI input module for the Marquee series)

How about this: Nvidia's video cards support custom resolutions, timings, etc. I check their technical documentation, and there's an interlaced mode available, which would cut the required bandwidth in half.

This probably isn't a common way to do it, but why not ask?

Thanks, Mark

[cmjohnson]

I've achieved 2048x1536 in 16:9 mode, which is equivalent to 2048x2048 in 4:3 mode, on a slightly modified 8500 test bed machine with a good nVidia graphics card. The modifications consisted of some capacitor changes to the focus board, neck boards, and
the use of FrankenYokes as well, which are focus yokes from Sony 1292s adapted for use on a Marquee. At that resolution, it was
"count the pixels" sharp on the CRT face, but this was slightly beyond the resolving ability of the HD-8B lenses. So I could never
get the image quite as sharp on the screen as it was on the CRT faces.

A 9500 should give 20 percent greater resolution capacity from the better HD10 series lenses ALONE, plus with the larger CRT faces,
another improvement in MTF at a given resolution, or an improvement in available resolution due to the larger writing surface, can
be expected as well.

I think Scott would agree with me when I say that a 9500 should be able to beat an 8500's resolution capacity by 30 percent if both
machines are dead stock. Start throwing in performance-enhancing mods and you'll rapidly find yourself in search of better lenses,
which is what's driving the cost of HFQ900s and HD10Fs up high on the used market.

In factory configuration, Marquees can deliver resolutions high enough to push the limits of their lenses, if the machines are in good
condition and well setup.

CJ

[mhalsan]

This all looks good- thanks to everyone!

From what I've read here, a top-end CRT unit will be superior to a digital model.

Thanks, Mark

[AnalogRocks]

[AnalogRocks]

[Mark_A_W]

[Zebu Fellenz]

I have to agree with Mark on this one, while I love my CRT's and wouldn't give them up for any digital you really have to have the right tools for the job. if you are running high resolution graphics and really need the resolution get a 4K digital or a few 1080p units and a blend processor.

Besides you wouldn't want to waste such a nice machine on "computer graphics"

Get a CRT for the theater and a stack of digitals with extra lamps for the "computer graphics"

what exactally are you doing where you need such high resolution.

BR

Erik

[mhalsan]

I didn't plan on doing CAD or anything like that- just games and movies.

A friend of mine has a modern Sharp DLP projector that has pixel-perfect resolution but there are no blacks, the colors are wrong and the bulb gets dim in a much shorter length of time than the sales literature would suggest. Whenever it gets an input signal with a non-native resolution the scaling fuzzes out the details. <<< All of this is well known >>> the LCD projector at work has similar problems.

From my own experiences with older analog chassis and from what I'm reading here, modern CRT projectors are superior in every way except full-white lumen output. I can deal with that- my room is 100% sealed with non-reflective black carpet, walls, ceiling and furniture. All it needs is a worthwhile projector.

thanks, Mark

[Zebu Fellenz]

Oh,

Well if all you will be doing is movies and games I would highly reccomend a CRT for you. A good 9" machine will give you all the resolution you should need. If you have the money to spend I would go for a 9500LC ultra with full MP mods

Erik

[mhalsan]

I noticed Curt has a 9500LC Ultra "on the way"
I wonder if he takes deposits.....

thanks, Mark

[Stonefool]

I don't know if I remember this right, but old workstation monitors could always get the highest resolution, shrapness wise, from "wire-frame graphics" for the specified bandwidth, however, displaying full-screen (DVD) video was another thing though, it all boilded down to the actuall amount of data sent to the screen. Hence the difference in sharpness (but important the "displaying" speed) when you displayed wire-frame vs solid textured models.

[mhalsan]

So, everything counts- source and the machine it's being played on, the quality of the video interconnect, and the specs of the entire video chain in the projector.

You mentioned 'wire-frame graphics-' were you thinking of vector graphics? I wonder if anyone has tried to do this with a CRT projector. Hmmmmm. There's an arcade emulator called MAME and a vector driver card from Zektor that support traditional vector monitors. The card is addressable to 1200x944. On a CRT projector, you'd need X and Y inputs to both deflection circuits. There would be a risk of ruining the tubes....best to try it on an old analog unit.

thanks, Mark

[AnalogRocks]

Vectrex x 3 (RGB)

[AnalogRocks]

Vectrex x 3 (RGB)

[Stonefool]

[David_Web]

I am confused here.
Are you talking about wire-frame as in showing polygons (lines between the dots) then plotting it out on a raster.
Or plotting a vector on a lithographic(?) display like a laser or scope?

Barco has a few lithographic(?) projectors made for simulators, HUD etc.

[mhalsan]

Well, in a vector monitor (as opposed to a raster display) the signal source directly controls X and Y deflection, with the Z signal being fed to the control grid of the CRT. Some classic video games like Asteroids used this method. The monitors typically included a spotkiller feature that shut off the beam if the input signals stalled- otherwise there'd be a spotburn in the center of the screen.

>>> Isn't it true that modern CRT projectors have a similar spotkiller circuit that cuts off the high voltage?

As you mentioned above, this is how an oscilloscope works in X-Y input mode- there's no horizontal sweep generated internally. Because of the vector display, apparent resolution was higher- there were no scan lines as such, and the analog output of the vector generator didn't have "jaggies" on horizontal lines.

This display method is useful for games such as this, or specialized displays in industrial settings. For movies and contemporary PC displays, we need a raster-stype display.

thanks, Mark