Cine8 Onyx, BG808s, conversions and blending ?

Well neither of my vanilla PG sets can get near as small spot-size as the Barcos even after having replaced every single dying capacitor in them.

Yeah the point convergence in the PG has a lot of points, but whereas on the Barco, I have +/-50 range of the adjustments and every single 'notch' makes a slight change, the PG also has +/-50, but visible change only occurs every 2 or 3 notches. It has more points to adjust, but often you can only overshoot or undershoot your target position with it. It's like less adjustments that are more accurate, VS more adjustments that are less accurate. Depends on the size of your screen how much you will notice that.

On the other hand, the "non-point" geometry and convergence settings of the Barco are much nicer. It's easier to do a good basic setup on a Barco.

Overall, I have to say they're evenly matched. The NEC has better colour out of the box, and more point convergence points, but due to the lack of precision in the adjustment that is only an advantage on smaller screens, plus it was never meant to use the tube-face completely, which means you'll either run your chassis extra crispy (it's not cool to begin with) or loose from the machine's ability to physically resolve higher resolutions. The 808s has the Sony tubes which are definitely sharper (even with misaligned magnetics), it has the 'twisty knob' focus rings that I much prefer over the rotating tabs of the NEC, With a HD6/HD145 you can get pretty much the same image as an NEC, but better tubeface use ergo better resolution of the image. The basic convergence and geometry setup is definitely better, the downside is the 'zone' convergence which admittedly gives too few zones of adjustments, but at least the adjustment itself is precise enough for my 3 metre wide screen where I don't have over-/under-shooting problems. My solution to the zone convergence thing is to do the best possible basic setup with the test pattern slightly larger than the screen, so I don't have to care about the very edges, then use an active image that's just that slight bit smaller (which still gives me near full tubeface use).

Onto the topic, got my blending units yesterday, and my HD18 set. It's the metal encased version to boot! They're going to make my projector weigh a few kilos more Now if only the COG and contrast mod boards would finally arrive...

That gives me a rough idea of what order to do things in, thanks! I'm waiting on my COG and Contrast mod board as we speak... Italian post guys are taking their time

Currently I'm experimenting a bit with lenses.

To clarify for those who might be looking for info on replacing HD215 on their barco (because there's a ton of contradicting information floating out there). Physically, you can mount a HD18 in place of a HD215 without any modification or the addition of a mounting plate (though there will be minimal light leakage between the lens and the LC chamber rim). But unfortunately the C-element would require the lens to be closer to the C element than allowed by the mounting ring on the LC chamber. So HD-215 C-elements will not work with HD-18 lenses, unless you are willing to have a few milimeters machined off of the rim of the C-element retaining ring, or mill the focus-bolt slot longer in the side of the lens. Since I don't want to have to mill anything, time to replace C-elements with the ones for the HD18.

I would love to get my hands on a set of HD117-24 to see if it'll work with the same C-elements as the HD215.

Addenda:

During my googling, I found Decibel's posts about his play with the LC hardware, thing is, the LC chamber+plate seems different from what I have in the Onyx!

Okay so I dismantled my extra LC chambers and checked this and that and how they're supposed to go together, and I have a few questions I'd really appreciate some help with.

1) It would be nice if someone with a G70 or XG could chime in on lens-C element distance. I would like to know how much distance there is supposed to be between the flat outer plane of the C element , and the metallic (or plastic?) rim of the rearmost lens element, when the main focus knob is all the way to the back. I think they're not supposed to meet, but I'd like to be as precise as possible. I am simply going to have someone with a lathe mill off a few milimeters from the rim of the C-element retaining ring so the lens moves closer, and that should solve all my problems, but I don't want to mill off more then I'll need so as not to weaken the ring too much.

Case in point, if I mill off 5mm, with the focus knob fully back, the rim of the C-element and the rim of the rearmost lens element will just touch. I am pretty certain that is unnecessary, and it will only leave 2.5mm of material left for the lens bolts. Even with washers or nuts I kinda think that's too thin.

If noone can give me info regarding this, I will have 4mm milled down. That'll leave 1mm between the C-element and lens. If it turns out that that is still too far back, I can always add washers for spacing the lens further. That will also leave 3.5mm of material left for the lens bolts, which, with a nut and a washer added from behind, should be enough to support the lenses safely I think.

2) Light leak between lens and C-element. Does this actually have an effect on projection (aside from possibly allowing dust inbetween)?

3) Glycol... Is the stuff used in LC the same as used in the coolant chamber with AC projectors? How 'white' is this stuff supposed to be? What I got out of my extra LC chambers is completely clear (no haze or fungus or floating things inside) but it does seem yellowed. What I got out of my AC chambers previously was always very nice and colourless. (And yes I do have all that AC coolant stashed safely

The glycol should be water clear, otherwise it will affect color fidelity.

Light leakage degrade the contrast ratio, it should be avoided.

I think the thickness of the fluid between the tube and C-element only shifts the focal point so I would say it is quite forgiving in that regard since the lenses have more focusing range than what is advised to them.

Yes the glycol is the same.

I found the step sizes on every NEC ive ever adjusted to be very fine and very accurate. But if you have not set astig perfectly, it wont really matter what else you do. I ran my 9PG at full tube face rasters for over 5 years with no issues at all, it was boarder line in the corners getting them aligned, but geometry was perfect and so was convergence. It was also bullet-proof stable, and never really drifted at all.

Based on what you have said about your NEC sets, i would say you have an older version of the software, where as i had the latest version, and it had more menus and more accurate adjustments. The earlier versions did not even have phase adjustment for the test patterns, which will cause the exact same over/under adjustment steps you describe.

Ive never set up an earlier Barco than a Cine 9, and knowing they have less points of adjustment than my Panasonic 51" rear projection TV, i struggle to see how it could ever really be perfect.

You can easily find in any earlier threads around forums discussing the Cine 9 and 909 where people that have set one up rave on about how great the convergence and geometry is and how easy it is to set. And theyre not completely wrong either, it is very easy to set, and it is very basic and straight forward. But it is also horribly inaccurate too.

I had to laugh at one forum thread i read with people boasting about the number of adjustments on the Cine 9 and i think it was Mark AW that mensioned it took them 9 years to get their system to a standard that was about half of what NEC had back in 1992. So very very true.

No matter how perfect you set the mechanicals, it does not change the fact that the horizontal centre bow adjustment is wayyyy too coarse, and sometimes setting it dead perfect means the top and bottom are near impossible to get right without using coarse and fine zone adjustments on green to get it somewhat close, which has an effect on linearity, and further knock on effect on red and blue convergence.

Another silly thing on Barcos is adjusting anything on green automatically does the same thing to red and blue, where as NEC give you the option to adjust only green or all three. Where the NEC has full and very comprehensive independent geometry adjustments for all three colours, Barco has reasonably basic rudimentry coarse geometry adjustments on green only, and absolutely nothing on red and blue apart from two levels of point/zone convergence, being coarse and very coarse.

When it comes to vertical lines on a Cine 9, you have to compromise between dead accurate vertical centre and the best you can get the right hand edge, because for some reason they seem to think the keystone adjustment needs to be quite coarse, and have only added a fine adjustment setting for left side ( which works well, you can always get the left perfectly vertical regardless of centre line, but it is always a trade off when it comes to the right, and it must align perfectly at all screen edges, as this is where it really stands out when lines are not straight or parallel to screen boarders )

Horizontal centre/top/bottom interaction is even worse, and also even more coarse. And to top it off, the sheer range of some of these adjustments is lunacy, its like as if they thought someone might want to project onto a beach ball, halving the range of adjustment by halving step sizes would be a huge step forward.

NECs are a complex machine to align for the less skilled person, but when you know what to adjust to get things right, it can very easily be 100% perfect. The Barco system is so basic anyone can align it reasonably well in no time flat, but to the skilled person, it is very lacking.

I think the plan you have to try aligning two Barcos of differing models is going to be very difficult to get looking good, if it were two Cine 9s i think you could easily be happy, but from all i have read about lesser models, the Cine 9 is streets ahead of the Cine 8, and you only have one of those to start with, the 808s is not going to compare to the Cine 8 overly well, and itll be made much worse by the very limited adjustability of those sets.

Not to say you cant make it work, but the end result is going to be pretty obvious youre looking at two different images on one screen, colour uniformity alone will be almost impossible to get right.

Mounting rings are at the machine shop, should be ready by tomorrow noon. If so, by tomorrow evening the Onyx will be on my ceiling.

Not really, the two PJs have the exact same boardset in them, once I have the same software and the same tube/LC setup, the only thing different will be the case colour (Okay the Onyx supposedly has a scaler too but that's not going to get any use anyways.)

I have the reworked mounting rings fresh off the lathe, time to do some screwing (Right after some RGB cable and RGB switcher repair...)