Upgrading from Sony KP-51HW40 (1080i CRTRP)

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

Hi Brian - Here's a rundown of your sources:

Upconverting DVD: 720p/1080i
Xbox: 480p
Xbox 360: 720p/1080i
Nintendo Wii: 480p

Bottom line is that none of your sources will be able to display at 1920x1080p. So unless you plan on purchasing an HD-DVD, Blu-Ray or PS3 in the next few years, I'd definately lean towards the HL-S6186W 61" model.

Keep in mind though that the HL-S5087W 50" model features much higher contrast, so I'd recommend you review both models carefully as you might prefer the PQ on this model!

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

'I'm currently becoming more and more disappointed with the PQ of my current set and am looking to upgrade'

What dissappoints you about the display?
Is your display calibrated?

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

When was the last time you had your CRTs and mirror cleaned? In addition, as Chris mentioned, tell me what was calibrated.

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

I would clean as suggested. If possible, I would also check beam focus while you're in there to see if that needs work. Also check optical focus after checking beam focus. The image at the screen is the product of two independant focus systems, so a blurry picture at the screen could be either.

When cleaning the lenses be careful not to let any cleaning fluid get into the lens.

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

Calibrate with PRO mode - it has the least amount of artificial settings - although you need to enter the service menu to turn them all off.

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

Brian: The wingnuts on the CRT lenses are for optical focus. By beam focus I mean the focusing of the electron beam itself. A projection CRT projects the image of the CRT tubeface onto a screen, in the case of an RPTV, onto the rear of a rear-projection screen surface. Oftern forgotten or misunderstood, is that there are TWO distinct projections, because the CRT tube itself is a sort of projection. The image at the tubeface is created by a scanning electron beam which must be properly focused onto the tubeface. When you view the screen, you are thus seeing the PRODUCT of two distinct projections, either of which may be out of focus. By looking at the screen and observing a blurry picture, you cannot tell which is at fault.

By looking at the tubeface itself through the lenses (careful!!! use sunglasses and/or drastically reduce white level) you can observe directly how well focused the electron beam is at the tubeface itself. If things are out of focus, beam setup and focus needs to be addressed. Note that your eyes cannot see the color blue very well, so it may always appear more out of focus than G or R. Blue beam focus is best achieved by adjusting beam focus and observing the brightness of blue which diminishes slightly when the beam is most tightly focused. Some blue defocus is often used for better light output/grayscale linearity.

Once you've established that beam setup is good (or rectified that if beam setup is poor), then you should check optical focus with the lenses and make sure things are well focused. You can also isolate optical focus by observing the inherent phosphor grain of the CRT tube on a white card, which can be done on a defocused white field that does not rely on beam setup being correct whatsoever. Using a sharpness pattern or a grid pattern at the screen while adjusting optical focus is limiting because it hinges on beam setup being as sharp as possible and as even as possible across the tubeface (unlikely).

Re: Upgrading from Sony KP-51HW40 (1080i CRTRP)

Hey Brian, no problem with the questions, it's a complicated field!

As to your first paragraph, yes, practice a little body contorsions! Or use a hand mirror or something.

For optical focus, I apologieze I was ambiguous when I said a 'defocused' white field. I meant electronically (beam) defocused so that the beam is a giant blobby blur on the tubeface. This eliminates any visible scanlines, you have a completely smooth white square or field. You isolate each gun and look for phosphor grain. This is difficult to describe, but once you see it you'll know. It's kind of a grainy pattern inherent to the phosphor itself from when it was applied to the tubeface. The best comparison I've found that someone may be familiar with is the structure of a piece of paper. Take a regular piece of printer paper and hold it up to light, and you can see if you look closely that the pulp that goes into making the paper is slightly thicker in some parts and thinner in others which with light behind it looks like it has this grainy kind of structure that you don't normally notice when you pick up a piece of paper. The kind of grainy structure of the phosphor is very similar. With a 3x5 card or something you can move the card through the focus plane while observing a white field with the beam defocused and somewhere in there you can see this grain come into focus. It's probably easiest to see on the green tube. The beam does need to be defocused enough to see an even field, if you're seeing scanlines and the like it will make it nearly impossible to distinguish the grain because you have scanlines 'in the way' so to speak.

Anyway, if you enjoy tinkering and learning about these things, it might be interesting to explore this.

If you are interested, this is written primarily for FP displays, however an RPTV is basically the same thing but with a mirror, a box, and a different kind of screen. It is by far the best setup guide for CRT projection I've ever come across. You may enjoy reading it now as you figure out what's going on with your display, or tuck it away for later:

http://www.keohi.com/keohihdtv/exper...ykuo_tips.html

see: Front Projector Focus
and CRT Astigmatism Adjustment, and the cleaning part too.