[Barcoing Mad]

Ray Mears vs Bear Grylls.

Ray is currently squatting on the floor glowering at the screen with his three eyes. He has a few issues - big, heavy, a bit noisy, glycol in one retina needs changing, a bit of banding - but all in all his strengths are clear.

Bear is soon to be perched on a shelf behind him. Leaner, fitter, but maybe just a bit too full of himself and about to plucked away by the production team in a helicopter.

After a few weeks, one of them will be out in the cold. (Actually not, I'm a big enough nerd to keep them both installed).

[Barcoing Mad]

There are two types of problem - problems that can be solved, and ones that cannot.

As an enthusiastic amateur, I find that CRT projectors tend to exhibit a host of the former, which with time and effort can be eliminated. For example, a good 9" machine can resolve 1920x1080 corner to corner. In practice, getting the set-up spot on is time consuming. Similarly, geometry can be very good - but again it means going through careful positioning, mechanical alignment, magnetic set up, convergence and so on.

Then there are a few harder problems - for example electrical noise on the signal, which can be dealt with through modifying or replacing circuit components.

An example of an insovable problem with a CRT PJ is the fundamental limit on ANSI contrast, or scan rates and bandwidth - 1920x1080 is stuck at 50Hz refresh, so will always be a bit flickery. 75Hz is out of spec.


The JVC gets some things right with ease - obvious to any digital user - focus, geometry and white field uniformity corner to corner are spot on.

Full resolution of 1920x1080 is there - albeit with the slightly edgy appearance of a pixel structure as opposed to the gentler Guassian profile of a scanned beam.

But I hold the impression that digital problems tend to be insolvable - if black level isn't there, then you're stuffed. If the above black field is splotchy and not uniform - glowing corners - ditto. If the convergence is non-uniform, then tough and so on.

The JVC, however, has good, if not excellent convergence (i.e I'm going to have to walk up to the screen and start hunting for errors), and the above black field is uniform.

Black level is more interesting - out of box setting revealed dark grey, and I thought uh-oh. But with a little tweaking, blacks began to look like blacks and it became a case of juggling black level against crushing blacks. So this looks like a solvable problem for another day.

Other impressions: The 750 has a full CMS. Good - it needs it. And I'm not quite convinced about the quality of the internal video processing. In theory it should be more than a match for the Crystallio 2.
I like the lack of fan noise, and the fact that it weighs significantly less than 80kg!

It's far to early to draw any profound conclusions - but for fun - I still rate a good 9" LC CRT with excellent set up at the top of the heap. The JVC, however is just bubbling under.

In terms of image depth and shadow detail non-LC machines are clearly outpunched by their LC peers. The JVC outperforms a decent 8" AC crt.

[Chris Frost]

These sort of comparisons are always going to be tricky.

IMO, digitals are like modern mass-market motors. They do what most people want, to a reasonable standard, and they do so reliably. CRTs on the other hand are closer in spirit to yester-years sports cars. So just how do you compare a £20K Mondeo with a mid-80s Lotus Esprit?

When you talk about the bandwidth limitations (1920x1080 @ 50Hz) are you refering to the signal coming in via HDMI/DVI somewhere in the chain?

[Barcoing Mad]

Yes, absolutely - I think your analogy is pretty good. And arguably a CRT PJ and digital machine differ technologically far more than a couple of cars! And if you love your Lotus, stick with it, as it will perform beautifully and reliably - but make sure it's tended to from time to time by a skilled mechanic (there are some good ones around!)

I find it interesting that all the CRT replacement technologies - LCD, plasma, DLP, DiLA - have struggled to match CRT's abilities. True, CRT is an old technology and hence developed (or stagnated), but off hand, you'd think a totally new approach could be initially much worse, or a lot better. In reality, they've slowly crept to a similar standard.

Bandwidth limitations for 1920x1080x50(or 60)Hz are due in part to pixel clocks supported by VP, and HDMI, and also by my PJ's sweetspot. I've used 1920x 817p x 75 (72) Hz successfully for 2.35:1 aspect. Again, it's down to getting a good PJ set up right.

[Chris Frost]

I was going to post that the active scanning window method is the way to go, but I see you are already there

It's kind of ironic that digital signals have a restriction whereas "old fashioned" analogue theoretically doesn't. Oh well, that's progress I guess

What does excite me about digitals is the opportunity to do a constant height screen at close to 1920x1080 resolution for 2.40:1 movies.

[Barcoing Mad]

I suppose with a fixed panel, limited input resolutions aren't a surprise. But it surprised me that it shows film based material with 3:2 stutter at 60Hz, rather than going for a multiple of 24 Hz. At least 24Hz input is supported.

Analogue is also good at handling motion, almost by default. It doesn't care if the input signal differs frame to frame, whilst fixed panels generally have some kind of memory effect due to inability to react instantaneously for whatever reason.

With this in mind, I've been looking for dithering, blur, smearing on the HD750. And have seen the lot.
Except that I was at the movies, watching Public Enemies. Something has apaprently gone wrong with Michael Mann since he's started to shoot digitally - every form of defect seems to be included...mosquito noise, edge enhancement etc.

[draganm]

Originally Posted by Barcoing Mad

Then there are a few harder problems - for example electrical noise on the signal, which can be dealt with through modifying or replacing circuit components.

I can fix that

Marquee HD Mods by Draganm

Originally Posted by Barcoing Mad

An example of an insovable problem with a CRT PJ is the fundamental limit on ANSI contrast, or scan rates and bandwidth - 1920x1080 is stuck at 50Hz refresh, so will always be a bit flickery. 75Hz is out of spec.

You can certainly do better than 50Hz, but not with the 10 to 14 year old components in the machine. I remember seeing the RS1 and having that jaw dropping experience. I can honestly say that after re-building/upgrading my Marquee with over 130 new parts pretty much everything improved, including ANSI contrast. I have a normal 8500AC hanging for the time being and the pic I have now is in may ways on par with The RS1 pic I saw 2 years ago.
I focused on the parts of the Marquee that are responsible for thermal instability (drift) and noise in the circuitry. Even without trying to increase the inherent band-width of the circuits, just addressing these 2 key issues makes a huge difference. By removing the noise and stabilizing the analog waveforms higher scan rates become possible.
It's important to point out that the electronic parts available today are leaps head of the stuff from the mid 90's. IT's like comparing 2009 tire technology to the rubber on a 1995 sports car. While micro-processors have increased greatly in speed and processing power, the power to drive them , cleanly (capacitors) has also leaped forward. The same caps also power the coils in a CRT which control the tube, these 2 things is where a lot of improvement can be found.

[Paul D]

I still love reading these kinds of posts.
I jumped the CRT ship earlier than most, and it was a move i never regretted.

As Chris can verify, i still respected the benefits of a good CRT though.
I remember the absolute joy and frustrations that tweaking a CRT can bring.

As mentioned, tweaking the hell out of a top end CRT can produce stunning results. But it gets to a certain point that you seriously have to ask yourself if it is worth all the effort.

If you are into CRTs as the actual hobby, then fine tweak away.
If its about actual ultimate image quality, then you have to pick your poison.

Coming into the hobby as a novice, i was swayed by the "CRTs are perfect-digitals are crap" fraternity.
I quickly dumped my Sony digital, thinking a CRT would be the end of my picture troubles.
It didn't take me long to realise that although good, my AC 8" CRT wasn't going to cut it.
So started the 9" LC trail.
The Barco Cine 9 was my holy grail, with the Marquee 9500LC as a more realistic financial choice. (with maybe a 1209s as minimum!)

I travelled the country looking at countless CRT setups.
I eventually realised that certain aspects of a CRT are not perfect, and only the very best tweaked ones are truly stunning.

Then we have to get back to the original reason for having a cinema room...the movies!
I spent far more time tweaking my CRT than ever watching films, and even then i would be lucky to get through an entire film without adjusting something.

After my switch back to digital, it took a long while before i could finally just sit back and relax.
I didn't enjoy the grey blacks, and i saw the odd DLP rainbow but overall i was still happy.

Digitals have finally started to produce an image that makes it very very hard to justify a CRT.
Yes it "seems" to have taken a long time for them to "catch up" to CRT, but most early digitals where nothing more than re-badged corporate machines.
And it does seems strange that they most of the digitals still haven't cracked total black.
I believe you can get a digital that has perfect blacks, but at a price that would rule it out for most people.
Having said that, high end CRTs weren't exactly cheap when new.

I do chuckle when people compare projectors to cars, because it usually shows their previous dream car(s). (mine was always the Lotus Esprit)
Most modern cars would out handle all but the very best sports cars from the past. However, horsepower always matters so you have to match them on BHP per ton.
I get nostalgic about (the old style) Minis every now and again, and go ahead and buy one.
After about six months, i realise why i also get rid of them!
This cycle continued for many years before the price of second hand Minis went through the roof.
So yes i love my Minis, but they had a time and a place. There was lots of things to love and lots of things to hate. I will always have fond memories, but it was time to move on.
Maybe this is also true of CRT...

I will read your views with interest.

[draganm]

Originally Posted by Paul D

I spent far more time tweaking my CRT than ever watching films, and even then i would be lucky to get through an entire film without adjusting something. .

your not alone here, a lot of people who posted in the past both here and other forums are exactly the same way. They just just can't stop fiddling and adjusting things. I think anyone who is prone to this habit is really better off with a plug and play device like 1080LCD. I don't touch my Marquee from months on end and never really understood the need to do so.
At this point the people left are mostly hobbyists and those who would like a $6K picture for $2K in exchange for the hassle of CRT. IT's not a large crowd but it's still fun hobby for me and other die-hards. Funny thing is while the market for a CRT is smaller than ever I do more with them now than I ever did back when they were king of the hill.

[Mad Mr H]

Originally Posted by Barcoing Mad

The JVC gets some things right with ease.......white field uniformity corner to corner are spot on.

The JVC.......black field is uniform.

I would like to hear if you feel the same in 50,100,200,500 hours....

MOST digitals suffer non uniformity at a very young age.


Although I use CRT myself I do vast amounts of work with digital PJ's. There is a place and market for both.....

I just did not expect that place to be your living room !!!

[Mad Mr H]

PS - If you want the very best mods for your Marquee then forum member "Swiss Steve" is the way to go .

He does a modular option, this gives an affordable path to follow if all in one go is beyond budget.

STEVE also offers repairs - Well worth knowing.


Link to above mods is a very reasonable price .

[Barcoing Mad]

Yes, I've heard only good things about Swiss Steve.

[draganm]

Originally Posted by Mad Mr H

PS - If you want the very best mods for your Marquee then forum member "Swiss Steve" is the way to go .

cool, I didn't know anyone else was working on these besides one other guy here in the states. Does Steve have a webs-site talking about his work or?

[Barcoing Mad]

Swiss-Steve is a member here. Drop him a PM to see if he's around.

[Nashou66]

Originally Posted by draganm

cool, I didn't know anyone else was working on these besides one other guy here in the states. Does Steve have a webs-site talking about his work or?

Steve and I have chatted a few times and he has given me lots of advice Dragan. the stuff your doing is along what he does but he takes it to the SMD level, kinda what I did with my mods on the CLM. I am going to implement some of his ideas once i finish the blend Set up of my longbow Ultras. Then I'll mod away one of my other 4 marquees and keep one stock to do comparisons with.

Athanasios

[Barcoing Mad]

It's a week and roughly thirty hours on the lamp later (100 hours total from new)

I prefer the way a CRT PJ handles motion (subject to it being fed by a decent video-processor). The 750 has a tendency to smear and colour step (loss of bit depth) in some instances. The effects are very hard to pin down and to distinguish from similar artefacts present in the source material (following play-back with CRT PJ for comparison), and I have the tendency to start searching for things which aren't there as opposed to enjoying the movie!

The exercise has also shown how badly my Marquees need professional set-up or a lot more effort from me - the colour temps and grey scale tracking leave a lot to be desired. I also have the opportunity to touch up the geometry as I can run the Quee and 750 as a stack.

It'll be interesting to see how the lamp ages. At the moment the image brightness coupled with its ANSI contrast give a punch and depth to the image that the Quee struggles to match.

[Boris Blank]

Any more updates on the 9500 verses the JVC?

[Nashou66]

Originally Posted by PaulB

Any more updates on the 9500 verses the JVC?

Paul dont you even think of it!!!

nashou

[Barcoing Mad]

There's a few hundred hours on the lamp and in truth I have nothing to add to my earlier impessions. It's a horrible admission to make, but I settle down and happily watch the thing. I've lost the nervous twitch to adjust convergence and geometry. I no longer hunt for poor corner focus. Adjusting astigmatism is a thing of the past. Thoughts of building a hush-box to reduce fan noise have deserted me...I'm no longer worthy of this forum.

[Nashou66]

Originally Posted by Barcoing Mad

There's a few hundred hours on the lamp and in truth I have nothing to add to my earlier impessions. It's a horrible admission to make, but I settle down and happily watch the thing. I've lost the nervous twitch to adjust convergence and geometry. I no longer hunt for poor corner focus. Adjusting astigmatism is a thing of the past. Thoughts of building a hush-box to reduce fan noise have deserted me...I'm no longer worthy of this forum.

See YA!!!!!!!!!

Athanasios

[Boris Blank]

Originally Posted by Nashou66

Paul dont you even think of it!!!

nashou

Of passing interest only Nash. If the price for the JVC drops to £2k or below I'd jump but until then its the Marquee for me

Thanks for the update John,

Paul

[crteaman]

C'mon barcoing, when are we having that Marquee sorting session?

We need to make it a fair comparsion.

James

[Nashou66]

Originally Posted by PaulB

Of passing interest only Nash. If the price for the JVC drops to £2k or below I'd jump but until then its the Marquee for me

Thanks for the update John,

Paul

Screw that for 2kL you can get another marquee and blenders !

well almost

nashou

[Barcoing Mad]

And now the gentle peer pressure to return to the fold, with the gentle but menacing insinuation that I can't set up a CRT-PJ properly (true).

It was like this in the last sect I escaped from - the Women's Institute Undersurface Iceskating Society...I had to wear drag with my aqualung - anyway, just the sort of thing my psychiatrist told me to avoid after I went on that crazed spree of factory resetting people's Quees with my remote from outside their sitting-room windows during the last world-cup. (Oh yes, I know the key strokes. And you should see the things I can do to the G2...)

[crteaman]

You escaped the last sect but the hounds have your scent (channel No 5 I believe?).

Got your Marquee parts here, you will be able to play with a 990 soon..if it takes yer fancy me ol china


James

[crteaman]

Ah ha! there you are,

I can see your little green on-line light (not colour filtered) flickering away.

J

[Barcoing Mad]

Is that a 750 without motion blur?

[crteaman]

I wish I could tell you what it's going to be, other than 'hand selected parts' and it's quoted contrast ratio and light output being a little different, that's the sum total of my knowledge on it...at the moment.

So are you 'STILL' trying to decide if Raquel Welch or Ursula Andress is the best?

Ho hum, back to the workshop for me,(gotta put this 700 in Birmingham tomorrow) I hope I make it to the door before the hounds smell your No 5 on my slippers.

J

[Boris Blank]

Originally Posted by Barcoing Mad

I've lost the nervous twitch to adjust convergence and geometry. I no longer hunt for poor corner focus. Adjusting astigmatism is a thing of the past. Thoughts of building a hush-box to reduce fan noise have deserted me...I'm no longer worthy of this forum.

You've not modded your 'Quee then?

[Barcoing Mad]

The Quee has a modded fan. Quiet by CRT PJ standards, bloody noisy by hi-fi standards.