CurtPalme.com Home Theater Forum

[fuchs]

okay, so I got this ISF-calibrated Epson TW-620 for free, but with a broken lamp.
So for the fun of it, I've ordered a new lamp. So far, so good.

After the initial 3LCD, native 16:9 ratio, no-convergence, 15-minute alignment, 1600 ANSI lumen output joys, it was movietime!
God, 2 meters wide, 1600 lumens of output brightness!

... then I noticed something was odd.
Dirty Harry's face was purple. The movie looked like it was shot on Super8.
Captain Picard's face was greenish. The Enterprise was floating in fog, not in space.
And this feeling that those 1600 lumens didn't really look like 1600 actually.
It felt even more dim than my NEC 9PG, which seems rated at only 800 lm.

As my projection surface is limited in height but not width, I'm now planning on setting up the NEC in 16:9.
The extra width was about the only thing I really liked about the LCD-projector

.. I actually expected more of this.

[CasetheCorvetteman]

Yeah mate, 1600 lumens, but 400:1 contrast ratio... Compared to your PG 15,000:1 contrast ratio...

[PeeGee9er]

That 9PG looks quite familiar

[fuchs]

[fuchs]

Okay, so I liked the extra width but not the LCD projector.
During christmas sale, I got me a 7' (2m) electric screen
Projecting on the wall was nice to begin with, but I didn't really have any space to go any wider.

It was a good time to try and re-set CPC/Astig, and re-set the image on the centers of the tubes.
I think I understand the importance of the CPCs better now. It seems related to focus at higher light intensities, kinda determining the 'landing zone' of the higher intensity signals.
I don't like working so close to high-voltage, but it was worth it. Less pixel smear when turning up the contrast.

I've now set it up in 720p @ 72Hz. I've reduced the H-porch settings by about 100 pixels, so I can use about the maximum width the projector will allow on the tubes. I figured that the extra heat generated on the sides would be compensated with the lower height of the (widescreen) picture compared to 4:3.

I haven't finished point convergence yet, but I'm pretty happy with the results so far.

[gjaky]

Hey, that looks pretty good! How is your syncing problem?

I have to adjust focus and astigmatism on my boss' 9PG, now it is soft like an ES machine, but it has been recently recapped and the whole unit has about 800hrs in it... I have a 6PG xtra and I really like it, but never saw a good PG plain in action, and am really curious about it.

[CasetheCorvetteman]

Bleed those tubes Onkel!!

[fuchs]

[Jeremy112]

[gjaky]

[CasetheCorvetteman]

You should bleed if there is no bubbles and you dont know when it was last bled, a few years ago by previous owner doesnt mean anything if there is no bubbles.

In terms of sharpness, the 9PG i have is very sharp, on 1080i the middle is almost as sharp as my XG, however the edges are not. For 2 reasons, its not as sophisticated electronics wize ( although still more so than almost any other projector in its day ), and its got HD-6 lenses instead of HD-144s. If yours isnt ultra sharp, you need to work on the focus, which youre going to get a chance to do after you bleed.

When doing alignment, make sure all images are centered and line up in the center of the screen WITH THE LID SHUT!!! Dont use static to get them lined up, its really not that hard to do this right.

To get the lens focus perfect, display a white screen, totally defocus electronically with focus pots on DEF board, then use binoculars to see the screen and turn lens barrel til you see the phosphor grain snap into view. Do the outer the same way, and make sure youve got the flapping rings the right way up, there is a little arrow on them, hopefully youve got a full set of the right ones

Set all focus settings to zero before doing astig, then before you do focus pots, turn off blue defocus, set center focus to -10 on all 3, focus with pot til razor sharp in the center group of Hs. Do the outers using the menus, but the center should stay on minus 10, cause that is where you set it before. Last thing you do is turn blue defocus back on.

I have not touched the convergence on my 9PG in over 12 months now and its pretty much right where i left it, no good reason it should move if you do this right

[fuchs]

oh ... wait a minute ... focus ...
I've completely forgotten about Center and Edge focus after adjusting the magnets.

[fast forward 30 minutes]
Well the Edge focus went from -18 to +80 but the edge-sharpness has improved a lot, wow.
Especially in the green and blue. I'll be back!

[CasetheCorvetteman]

Sounds like you jumped the gun abit here

Dont play around too much, the tubes have to come out yet!!

[fuchs]

Yes, well ... I did, indeed. I just had to watch something to check out the extra sharpness.
Reading the "Bleeding CRT" pages and watching the videos now.
I plead err ... innocent...

I just figured out that swapping cracked tubes would be even more work than bleeding them.
Thanks Case/Jeremy for pointing out the consequences.

As for the electronics... I'll just leave it for now, maybe some DEF/SYS boards turn up somewhere soon.

[fuchs]

I really, really, hate you guys
I'd rather have had the illusion that everything was just fine.

There are indeed no bubbles in any of the tubes.
Thanks for the extensive how-to, Curt.
You've probably heard that before.

[CasetheCorvetteman]

Bet youd have hated us even more if no one told you to bleed them and one broke, spilling glycol into the guts of your fine machine!!

[fuchs]

Well, I can't hate you for telling the truth, of course.

It felt more like a rite of passage, unscrewing tight phillips-screws at the end of a thin glass tube neck.
And again, almost stripping the tight red tube's bleed screws.
And buying a syringe without trying to look like a junkie

The bleeding was not spectacular, the glycol just slowly came out a bit.
I've found some new screws to put back in. Do I clean with alcohol or something like that?

[gjaky]

The screws must made from some stainless material, as glycol is highly corrosive.
I found it easier to leave all the magnetics where they are, and pull the plugs instead.

[fuchs]

oh. Two more things I didn't think of. Thanks.
As a matter of fact, I just may try to put on the magnetics before putting the tubes back in, sounds like a good idea
Are the magnetics under high voltage? I'd have to probably turn them with the set on to get the picture lined up mechanically.

[CasetheCorvetteman]

Just dont touch the conductors and youll be fine. Its pretty easy

Make sure you null all settings before you adjust magnetics. I always leave them in the set with a plain PG, personal preference.

I havent ever replaced screws that hold in the coolant before