CurtPalme.com Home Theater Forum

[CRT_Ben]

[draganm]

[perisoft]

[ecrabb]

Or, Gary could avoid all that dinking around and just hook it up with the DVI cable and have perfect 1:1 pixel mapping automagically.

Gary, if you have an LCD monitor and a video card that have DVI, but you're using VGA, run, don't walk, run the computer and order a DVI cable from Monoprice.

SC

[perisoft]

[ecrabb]

That's a poor assumption. Most everybody here likes dinking around; but depending the individual in question, there's quite an array of things we like or do not like dinking around with.

For instance, I love dinking with CRT projectors, but DETEST dinking with Windows hardware device drivers.

SC

[garyfritz]

SC, my laptop doesn't have DVI out, or I'd have switched to DVI long ago.

[ecrabb]

[garyfritz]

Aha. Right you are, Steve. It looks significantly worse with ClearType turned off, especially italic fonts. But the Windows ClearType "tuner" you linked me to lets you improve it. Supposedly it doesn't work in Vista but it sure looks better to me.

Thanks for the pointer! Even if it's embarrassing that I have to get Windows advice from a Mac bigot.

[ecrabb]

Hey, I'm no Mac bigot, man! I just have my preferences - just like everybody else! I just don't understand why the Windows sufferers keep coming back for more like it's going to get any better! Like Vista Service Pac... er, I mean Windows 7 is going to suck any less! I guess it's a form of Stockholm syndrome... OK, maybe I'm a bigot... I digress...

Seriously, though... The only reason I knew about the ClearType issue is because I do screen caps all the time as part of courseware development, and way back when we switched from Windows 2000 to XP, I had to find the solution. I've had to help a dozen other people resolve the issue the last 5 or 6 years, too - so it stays fresh.

Mac OS X has a nearly identical feature called "font smoothing" that like Windows, you can tweak in 5 or 6 steps. I turn it off on both OS'es when I'm doing captures.

SC

[garyfritz]

Honestly I am NO fan of Windoze or Microshaft. I'd MUCH rather run on a Unix base like OS X, and I'd MUCH rather support Apple than the Evil Empire. But my clients use Windows and require me to use Windows. I know I could run Windows on top of a Mac -- so I could buy more-expensive hardware and pay for two OS's and two sets of apps? No thanks.

I frequently do screen caps for courseware development too, and I should have figured this out on my own. I guess I never thought to connect the fringing I see on the screen and the fringing I sometimes see in the screen-cap program, assuming it was an artifact of the program's magnifier. Duh.

[skippyar]

[garyfritz]

I don't know about the capabilities of the HD6CML lenses, but I suspect those aren't your weak link. You've got an ES projector. ES tubes are inherently less sharp than EM tubes. And they lose sharpness with age. If you have a lot of hours on your tubes, they're not even capable of what they used to do -- which was never as good as what an EM projector can do.

I've run 720p on an ES projector (Dwin HD700) and it looks good, but it's clearly past the limits of the projector. ES tubes are just not as sharp as EM.

[skippyar]

[garyfritz]

The "green tint on dark images" is just a calibration issue. See what I told dturco in this thread.

Blue SHOULD NOT be as sharp as R/G. Your eye can't focus well on blue so it doesn't matter if it's not sharp -- and CRTs need to defocus blue so the blue doesn't crap out in bright areas. See this post for an explanation.

I dunno what controls you have with the Barco, but the first thing that comes to mind with your "defocus in the corners" issue -- especially if you've already tried to resolve it with convergence &etc -- is optical. Most lenses have two focus knobs -- one for center, one for corners. Have you adjusted yours? There's also Scheimpflug adjustment, but if you're sharp in the center and out of focus in ALL corners, that's more likely the corner-focus adjustment.

First time I've seen the Spice Girls used as a test pattern BTW.

[skippyar]

[Kiev Savoie]

http://www.flickr.com/photos/skipster/3566591323/sizes/o/in/set-72157618825049144/

I did something similar to this for a rear projection system. With the rear jacked up above the front end like that it allowed me to fold the light beam in the most compact way i could figure out. The great thing about this is that you can get a pretty much perfectly square raster on the tube face and utilize every last bit of phospher (Assuming the lenses are dead even with the center of the screen and level on the zero axis). The not so great thing about it is that I can't get the bottom of the image to focus very well, it's pretty soft and i have not figured out what to do about it (if anything can be done about it!).
Your situation would be much better served by a standard ceiling mount. If the unistrut is too expensive for you a couple of boards laying on top of your rafters with treaded rod coming down off them through your sheet rock works very well, just be advised to get your beam geometry right because this setup is not adjustable.

[garyfritz]

Well, it's a little tough to see from your picture, but yes, it might be Scheimpflug issues. Especially where you have the projector mounted at an angle like that -- most projectors are designed to run "flat" and they have a built-in offset to display the image above the projector (with the PJ base flat on a table mount) or below the projector (with the PJ base flat on the ceiling for an upside-down ceiling mount). See e.g. p. 16 of the BG800 manual. If your focus is sharp in a band across the middle of the screen, but fuzzy at top & bottom, you've got a Scheimpflug problem.

Your projector is right-side-up but on the ceiling. If it was mounted "flat" it would be projecting up above the ceiling. By tilting up the rear to center the image onto your screen with the PJ "right-side-up" on the ceiling, you're working against the built-in vertical offset, and that WILL cause major Scheimpflug problems. The projector is designed to project to a flat vertical surface above the right-side-up PJ. The optics are aligned so the vertical screen is in the proper focal plane. By tilting the projector you've tilted the entire focal plane, and now it's focusing on a plane that is behind the screen for the top half, and in front of the screen on the bottom half. See the attached pic -- I took the setup image from the BG800 manual and rotated it the way you've rotated your projector.

It's easy to verify this. Get your center focus as sharp as possible. Now take an index card or other rigid piece of white paper. Hold it at the center of the screen, then move it out toward the projector. The image on the card should get blurrier as you move away from the sharp-focus point at the screen.

Now move the card down onto the bottom half of the screen. The image should be blurrier there. Now move the card out toward the screen again -- toward the proper focal plane as shown in the picture -- and see if the image on the card gets sharper as you move it out. If it does, then you definitely have a Scheimpflug problem.

The solution is "easy." "All" you have to do is flip your projector so it's upside down with its base parallel to the ceiling. Then your setup will be more like the picture on p. 16 of the manual, and you should have good focus across your vertical screen.

Honestly, though, if you're going to go to the trouble of pulling the projector off the ceiling, you really ought to consider replacing it while you have it down. Good EM-focus projectors are getting stupidly cheap. You'll be astonished at how much sharper and clearer the picture will be with a BG808 or Marquee 8500 or similar. It's not subtle. It's a night-and-day difference.

[skippyar]

[skippyar]