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-   -   Stewart Greyhawk Beta - First Impressions (http://www.avsforum.com/forum/23-screens/19312-stewart-greyhawk-beta-first-impressions.html)

tommyboy2 12-20-2000 07:57 AM

Mr. Stewart was kind enough to let me share my thoughts on the greyhawk screen up here on the forum. I'm eager to hear how my fellow beta participants are doing as well and think constructive feedback will be taken quite seriously by Don and his folks. They are an impressive organization.

To begin with, I currently use a lowly Draper Targa 1.0 gain 80x45 electric dropdown. The Greyhawk arrived in kit form and from the moment I began to open the box I knew I was dealing with attention to detail in every conceivable way. It may seem silly, but they almost overpack this the screen...you get the sense that you are opening something special and worthy of the Stewart name.

Setup was painless. They sent me a wall hanging kit and the thing was put together in less than 10 minutes. So far so good. Before I hung it I placed it overlapping the Draper so that I had a split screen. I fired up the Sharp to compare the blacks and contrast side by side.

Overall the blacks were marginally better and the whites were barely affected. The amazing thing to me though was the amount of shadow detail I noticed on the Greyhawk. It was subtle, but quite evident. And to use an overused expression at times up here...it looked almost 3D. http://www.avsforum.com/ubb/smile.gif But really, the amount of shadow detail it revealed was rather striking. I had fully expected to have great blacks and grey-whites. But this was not the case at all.

I'm very impressed with the screen thus far. As many of you know I just bought a D-ILA G11 recently. I plan to evaluate the screen with it over the holiday. Thus far I've tested it with my Sharp DW100U as I told Stewart I would and find it to be a nice improvement for LCD. The D-ILA should look even better IMO.

I had asked if the gain could be lowered even more to say .82 or even .8 and was told that the screen would be too dark for many projectors on the market. Right now the screen offers a gain of 3 units of black per 1 unit of loss in white. The result is the increase in contrast by 22%.

The only real problem I saw, and it was minute, was that from approx 30 degree viewing angle I thought I could see glimmers (for lack of a better term) from the optical coating that is on the screen. It was only discernable in small extreme white areas and happened very quickly. Nonetheless, this was a bit disconcerting.

Surprisingly, the whites are dampened but not to the degree that I've seen with some make-shift grey screens or Da-Lite's poor attempt at a grey screen. Alan Gouger can tell you that I've not been a fan of the grey screens I've seen thus far. The Greyhawk has made me a believer. Or to steal a line from Chrysler..."this changes everything"!


Dean McManis 12-20-2000 11:40 AM

Since Tom posted first I'll just add my comments to his thread.

I got my screen and eagerly set it up last night, so these are initial impressions.

I agree with Tom's comments about packing. I used to work in the damage and rewrap section of UPS, and most of the damaged parcels were due to poor packing. My screen came in two boxes. One was a thick cardboard tube with the screen material rolled up, and the other was a long rectangular box with the frame.

Everything was wrapped internally with paper, plastic or foam, with packing between pieces. This was really nicely done, and most welcome because the worst thing would be having to return the screen even before starting installation because of shipping damage.

I made a mistake in my sizing dimensions, even though Don asked detailed questions as to screen size. I had made my last screen frame, and my two previous screens before that had the snaps and black screen edging about 1" thick and butted up against the outside edge of the screen frame.

The Stewart screen frame was a nice black velvet edged model, where the screen material snapped in from behind and there was a beveled "picture frame" edging on the frame face that extended about an inch on all sides beyond the screen material edge, and roughly 3" beyond the viewable image size.

Unfortunately, this made the frame about 2+" taller than my lowest ceiling beam, and I had to notch the beam to fit the screen in. Still, it's nice and snug now, and all of the frame pieces fit together perfectly. If you are considering a fixed frame and have tight area diminsions, remember to figure in the outside frame size (OD) when ordering the screen.

The screen already is smooth, where some of my past screens took a while to smooth out fully. Also it's important to mention that even though I can smell the vinyl screen material, my last DaLite screen had a unbearibly strong vinyl smell for at least a week, before it toned down to this level.
It was dizzying. The GrayHawk's smell is not noticable from my main seating (15' away) and will no doubt get better still with a couple days to air out.

I've seen a bright D-ILA projector on a gray painted wall, so I figured that the whites would "look" relatively white, which they do.

My expectation was that the GrayHawk screen would be grayer than it is.
On it's own it looks slightly off-white unless you set it next to a white screen.

I just set it up last night, so I haven't put the screen up side-by side with my previous screen yet for comparison, so my initial impressions are of the GrayHawk itself with my JVC G15 D-ILA FPTV with an ISCO lens.

I expected the blacks to look blacker, and they do, but not to the extent that I had thought. My FPTV is calibrated, so it already has pretty good blacks, and the measured contrast was 500:1 (not checkerboard).

My brightness was previously set to -7 with the 180" 16:9 1.0 gain DaLite perforated screen, and it is now set to -1 with the GrayHawk screen.

The biggest improvement so far was in picture detail, both in shadows and with textures. This improvement alone would be worth getting the screen for a fervent videophile.

My last projector was a Sony 1292Q which had 9" CRTs, and the added gray scale range and picture detail remind me of the better qualities of the CRT FPTV. The GrayHawk adds an exra level of picture depth that I could easily see. The impression was like wearing polarized sunglasses.

My friends that I had over to help me install the screen said it looked great, but I'm not sure if they saw a difference that I did.
I have certain demo clips like The Fifth Element, Lost in Space, A Bug's Life, and some HD demo recordings etched into my mind as far as picture detail, color goes. Everything was visually improved, and I could spot extra depth and detail in all of the clips.

My friends were stunned with the HD football footage that I had recorded, and said that I should charge admission. http://www.avsforum.com/ubb/smile.gif

The audio was clear sounding, but I still have to add the THX filter for the center channel and specifically test some DTS movies and music later.

The other improvement that I noticed was the screen perforations, which were smaller and more dense than on my DaLite screen. Previously, I could see the perforations from abot 13' away, but not from my main seating (at 15'), but now they are hardly noticable from my close seating at 8' away, which is great. There was no visible moire effect at all.

Anyway, I was up until 3AM this morning watching demo material, and I'll do more specific testing later, especially audio testing and side-by-side comparisons with my other screen, using torture material like Dark City.

I'm looking forward to seeing the DirectTV HD demo (especially the Discovery HD material) with this screen later tonight.


Ron H 12-20-2000 01:05 PM

To All:

I had stared another thread on my Beta test. My question is would everyone prefer sepeate threads from each Beta Tester or all of them under one thread?

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

tommyboy2 12-20-2000 02:14 PM

No offense Ron. I must have missed your earlier post. I say we put 'em all in one place.


Ron H 12-20-2000 02:40 PM


No problem. I will move mine over here.


Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

Ron H 12-20-2000 02:44 PM

The GrayHawk screen arrived at my office on 12/19 at 10:00AM. The box weighed 58 lbs., was about 9 feet long and 10†wide top to bottom and front to back. The box was a little banged up. The staples at the ends had been pulled out and the box has a few dents. This did raise a concern as to what the condition of the material inside may be. The Fed Ex guys need to be more careful

Upon opening the box my concerns about the possible damage to the material inside was relieved. Everything was packed in an extraordinary manner. Lots of bubble wrap with everything was secure
and tight. The time and care that put into the packaging heightened my expectations to the quality of the screen.

Inside the box was a Snapper Deluxe Screen 54â€X 96†with a felt covered frame. I decided to tackle the assembly and install on my own with no assistance. If anyone wonders why Stewart screens are considered the top of the line they need to see how even the small things are done. From the packing to the workmanship of the frame, it speaks quality. The difference in the care and finish between the Stewart and my other screens is quite noticeable. Even the three wooden frame braces that run vertical on the inside of the frame, which will not show once the screen is inserted, have a very light gloss black finish. The black finish on these braces is as good as that I have seen on many subs.

Each piece of the frame is color coded and numbered. Assembly is almost goof proof. The frame itself has a wide velvet covered border. Once the frame is assembled, the screen is mounted using snaps. One caution is that the screen itself is marked top and bottom so be sure you have it oriented correctly before you start snapping it into the frame. This should be mentioned in the directions.

Snapping the screen into the frame was not near as difficult as the Dalite screen was. With the Dalite, I had to resort to pliers to pull the screen over the last few snaps. When completed the screen is quite taut with no wrinkles. Total mounting and assembly time was one and half-hours. This is the third screen I have mounted in my home theater room so I am aware of some of the pitfalls that arise when you mount a projector screen.

The screen material itself seems to be made of some type of vinyl material that appears to be quite durable. It has a light gray cast, maybe about a 20% tint and appears to be somewhat reflective. Once mounted in the black felt wrapped frame and placed on the wall it appears to be white. My wife did not notice a difference in color.

A review of the Sony 10HT image projected on the GrayHawk will follow shortly.

Ron Hastings

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

Ron H 12-20-2000 02:47 PM

Part 2

Now on to my first impressions of the image. This test is being done in a dedicated home theater room with total light control that has quite dark blue/gray walls and ceiling. . My first look will be with the projector setup as it had been with the Dalite High Power Screen. The Sony 10HT is mounted on a 8 foot high ceiling and is about fourteen feet from the screen. My viewing position is about 13 feet from the screen. The room measures 17.5†long by 14.5 feet wide. The screen is on the 14.5-foot wall.

The first DVD I reviewed was The Fifth Element. My first impression is that the colors seem to jump out a little more. The colors seem to be more CRT looking and there seems to be, the best I can describe, a smoothness in the colors that was not there before. There definitely seems to be an improvement in the black level with no loss in the white level.

The picture itself may be a little darker than before but no enough to be a issue. In fact, it seems obvious that the settings I used for my previous screen will need adjusting. The one change I need to make is the brightness level. The blacks are so much better that it appears I will have to increase the brightness to regain the shadow detail. The picture seems to have taken on a more 3-D look to it.

There definitely seems to be a increased depth of image. I left the Cinema Black turned on and see no need to turn it off. One little side note is that I have a stuck on blue pixel that shows up when it is in a black part of the picture. Its brightness seems to be reduced about 50% and is not a issue any longer. The color of the screen seems to help hide the pixel structure. I can walk up much closer to the screen before the pixels become noticeable. I am not quite certain of the reason for this effect.

I was able to turn the wall sconces and the lights in the rear of the room and still maintain a viewable picture. One of the large differences I noticed with the GrayHawk Vs the High Power, is how little the picture changes when viewed off center. The colors and brightness remained quite strong and consistent at an angle well beyond one would use for viewing. One of the problems I ran into is the movies so much better that I become involved watching then instead of jumping to different scenes to review.

I had used the Avia disc to set up the Sony for the High Power screen and have now done the same for the GrayHawk.

My settings are:

High Power GrayHawk

Contrast 92 99
Brightness 42 52
Color 54 53
Hue 50 50
Sharpness 50 54
Cinema Black On On

More to follow.

Ron Hastings

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

Phil Olson 12-20-2000 08:45 PM

I got mine yesterday but only had time to open the box. I concur that the packing is first rate. Definitely a class act.

I currently have a StudioTek 130 so this should be an interesting comparison. I'll hopefully get to it on Saturday.


propeller_beach 12-21-2000 05:32 AM

Hi Tom,

Since you started the thread, I'll ask you:

Are comments/questions for you testers allowed here by other members?

Thanks for the reviews. They are invaluable for those of us who are sitting on the fence and are not as lucky to test prior to purchase.


Ron H 12-21-2000 05:41 AM


We are free to answer any questions or comments you may have.

Ron Hastings

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

alm 12-21-2000 07:03 AM

For Ron H.

I have the Sony ceiling mounted and I am currently using the wall as a screen. I had been considering the Dalite screen you are currently using, but wanted to see how the Gray Hawk would perform. Can you give me an idea on the perceived relative brightness between the two screens. I know the Dalite is rated above the GH, but since the projector is ceiling mounted all the brightness is not reflected back to the viewer.

Thanks for the great review.


Jeffrey 12-21-2000 10:52 AM

Hi Guys

I received my Greyhawk yesterday, but have not had time to open it. Reading your comments has me very excited. Stewart Filmscreen, and specifically Joaquin Rivera, has been a pleasure to deal with. Their professionalism is first rate. I will be using a Dukane 9000D (jvc G10) and the 49"x87" Greyhawk. I have on hand a Dalite H.P., a Dalite G.B., and a piece of DaMat.

Jeff Streitz

[This message has been edited by Jeffrey (edited 12-21-2000).]

propeller_beach 12-21-2000 12:16 PM

Hi, and thanks Ron.

Dean McManis said:
"The other improvement that I noticed was the screen perforations, which were smaller and more dense than on my DaLite screen. Previously, I could see the perforations from abot 13' away, but not from my main seating (at 15'), but now they are hardly noticable from my close seating at 8' away, which is great. There was no visible moire effect at all."


I have been holding off on a microperf screen purchase for my DILA G-11 since this summer. My main seating position is at 11 feet from the screen plane. Though I had exchanged emails with Dean a number of times, and I was reassured that the Dalite was performing great in his setup, I was still a bit concerned (ok...a lot concerned, or otherwise I would have just given in and purchased) over the size of the perfs. I could not afford to make this mistake, not with the 11 short feet that separate my eyes from the picture.

I am thankful I am now able to read that the perfs will not be a problem at all with the Stewart I plan on purchasing! I am grateful to Dean. He always seems to be there with what people are in need of knowing; always in a timely and informative manner. He has always come through for me, and I thought after praising him through email in the past, I would just add a word or two here for everyone to know what a helping hand of a great guy he really is!

Now, if I could only get my hands on one of these Stewarts. Anybody know where I could get one? I have been in contact with Dennis Erskine all this time during the construction of my theater, but I have not heard from him in a long while ( I understand he is a Stewart dealer). I am trying to reach him to no avail. I need to have this screen by mid january or as soon as it comes out. Can anybody point me in the direction of someplace I can purchase this screen from, in case I do not hear from Dennis in the next few weeks?


Carey P 12-21-2000 02:24 PM

Just got the screen today at 2:30pm. It was delayed because they had the wrong phone number, but now it's here and I'm a happy camper. Thanks to Joaquin for sorting that out! It came by an air freight company in one 9' 3" box weighing in at 56 lbs!

I must add to the rest of the glowing comments about the packing. I've never seen such a professional job. Everything in its place. Nothing left to chance. Even the instructions didn't have crease anywhere! I was so impressed I had to take a break before starting assembly. But it won't be a long one!

It's a 54"x96" and I'll be testing it against the Draper M2500 and the famous black-out material screen (which is what I've been using lately instead of the Draper). The projector is a Sharp XV-DW100U at 15' back, ceiling mounted. More to follow.


Ron H 12-21-2000 03:52 PM


I am looking forward to read your comments.

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

Dave T 12-21-2000 04:39 PM

Originally posted by propeller_beach:
Can anybody point me in the direction of someplace I can purchase this screen from, in case I do not hear from Dennis in the next few weeks?
On Stewart's site, they have instructions for ordering directly from them, at http://www.stewartfilm.com/pricing/default.htm . Or, I'm sure they could put you in touch with dealers in your area.

And, echo your comments on Dean. He's been very helpful to me, too.

- Dave

Carey P 12-21-2000 09:33 PM

Update: Spent an hour or so setting up the screen. The hardest part has to be those snaps. Wow - tough on the fingers and the vocal cords, but once their in that baby is smoooooth! Nice finish.

Spent the rest of the night viewing various DVD's and doing AVIA setups. Also did some A/Bing (horizontal split) comparing the GrayHawk with the Blackout and M2500 screens. Jotted down many numbers which I'm still sorting out.

My initial impression seems to be on par with most others. It was a more 3D-like appearance than what I was used to. Much more filmlike. I started to get involved with the movie very quickly.

There were no artifacts from the screen itself, and in fact it seemed to eliminate or smooth out those that I remembered seeing before. The blacks were definitely blacker. Compared with the flat diffuse blackout material, it was not as washed out and there were richer colors with no color shifting at all. The contrast was certainly better. There was no pressing need to adjust the projector at first, from the settings I had with the Blackout material screen. However, as I'll post later, I ended up with a much higher brightness setting, but less Contrast. Color and Tint didn't really get affected.

Compared to the M2500, it was a much smoother picture, with no hotspotting. However, with a high white field on AVIA I could see a sheen that would follow me from side to side. But this was not annoying at all. Nothing like the M2500 hot spotting and color shifting. The artifacts or screen texture contributed by the M2500 outway any benefits of brightness. The smoother picture from the GrayHawk was much more appealing.

Alright. I have to end this now. Will continue tomorrow with numbers. My wife's getting her Lasik eye surgery in the morning so she'll be able to watch the movies without glasses. Lucky her. Hopefully all will go well and I'll get back to the review sometime after.

Overall, I'm very impressed!


Ron H 12-21-2000 09:48 PM


There is a small difference in brightness between the two screens. The GrayHawk does not seem as bright. As I do not have a devise to measure this I can not determine the amount or even be sure if the perception is due to the blacks looking deeper.

I did not feel any need to turn off the Cinema Black to increase the brightness. Even with lights turned on the picture was pretty solid. One of the big differences is how little the brightness falls off on the GrayHawk screen when you move off center. Once off center the brightness of the High Power screen starts to drop off rather rapidly.

I also noticed that the light reflecting back from the High Power tended to really light up my ceiling. My ceiling is painted fairly dark but it still tended to reflect light back into the room. With the GrayHawk this problem has disappeared with minimal light wash on the side walls.

Lex/MC1, Cinepro, SL3, Logo, Tripoles, Sony 10HT

[This message has been edited by Ron H (edited 12-21-2000).]

DanHouck 12-22-2000 06:13 AM

What projector are you using, what is screen size?



propeller_beach 12-22-2000 06:21 AM

Thanks very much, Dave!

Don Stewart, looks like you have a winner here! http://www.avsforum.com/ubb/smile.gif


Carey P 12-22-2000 11:20 AM

The screen size is 54" x 96" and the Projector is a Sharp XV-DW100U (LCD 1024x768 spec'd @ 1000 AL). Now for the rest of the story:

Projector at 15' back from screen ceiling mounted even with top of screen. Sitting position approx. 13' back. Screen mounted roughly center within 22' wall. 8' ceiling. White walls, no ambient light at all during tests. I'm using the Cygnus processor (plastic edition).

I am using a Toshiba 6200 DVD in Progressive scan mode to 480p input. The Edge enhance is ON but only at first of 3 levels available. This is mainly to improve the softness I get in Progressive mode. Also, there is the fact I don't have a Sharpness setting on the Projector in 480p mode.

I will list some comparison numbers here but this was really after calibrating with AVIA and double checking with some reference DVD's. Note that the Color and Hue settings are not affected. There is a wide range on the Hue (Tint) and Color on this projector, so it doesn't say much if they are off by several numbers.

Blackout Mat'l Draper M2500 BlackHawk
Cont: +8 +24 +8
Bright: +1 -3 +2
Color: +1 (-6) +1 +1
Hue: -2 -2 -2

The -7 was how I had it set before making the AVIA adjustments, and then decided to leave it with the higher setting for better saturation and help with comparison.

My initial impressions of the screen with lights on, projector off, was that it looked gray (against the surrounding white walls and ceiling). But no where near as gray as the HC DaLite sample I had. I also notice the little "sparklies" in the coating and I was hoping they would not be noticeable in the image. One thing I didn't like about the Draper, was the texture being very noticeable in bright scenes. I don't like to notice that there is a screen there at all. Without looking very closely at it (and I stress very) it looked very smooth with no variations or streaking.

I was amazed the first time I saw an image, that there was no structure visible and the whites really looked white, at least to my eye. The blacks were much deeper and the screen was less diffuse. It really looked 3 dimensional and I don't even have a D-ILA!

I did split-screen tests with the black-out mat'l and the Draper using the AVIA. I noticed some interesting things:
Comparing to the blackout mat'l: The brightness test bar chart showed equal brightness at the 50% bar, but down at the .8% level it was darker on the GrayHawk. On the tests where you have the ire black bars moving back and forth, I somehow expected to see a difference here, but I did not. There was a somewhat grayer cast on the GrayHawk when splitting the white field tests at most levels, but this was expected. Without a comparison like this, you would think it was as white as could be. The brightest white fields show a small level of reflecting "sheen" on the GrayHawk that would follow you out to maybe 70°. Nothing that I noticed in bright scenes of movies.

The Draper has such structure in the screen (and I'm not even talking about the streaking problem) and is so bright at center, that it makes the effect even worse. It is actually almost blinding in comparison to the GrayHawk. However, with supposedly a 1000 lumens, The picture is far better on the GrayHawk without the specular reflectance. The smoother picture is far more pleasant to watch and still retains most of the contrast of the Draper.

I believe that the Draper (all its other faults aside), has more contrast range to work with than the GrayHawk. And the Grayhawk has more than the Blackout mat'l. One reason I say this is because I had been using the Gamma 2 setting of the Projector when using the Blackout mat'l to improve contrast and shadows. With the Draper I always had it set to Standard. The Gamma 2 was a bit too much (though my wife seemed to like that CRT effect). With the BlackHawk, I find I can use the Standard setting again on most DVD's but occasionally want the Gamma 2 depending on the transfer. I think this is more a projector limitation (or necessity) and subjective more than anything else, but it tells me the BlackHawk has the contrast and brightness needed, but not quite the dynamic range of the 2.5 gain Draper, if that makes any sense. Maybe it's just me or the Sharp. But this could explain why I was able to get away with a +24 Contrast setting on the Draper. Still I would take the BlackHawk any day over the Draper.

Another point I want to make is that the Draper has a subtle but noticeable color shift in bright scenes. I saw no color shift with the BlackHawk. As well, the Blackout Mat'l screen had a yellowish cast and a washed out diffuse image as compared to the BlackHawk.

I did not notice any drop off in image brightness to the sides, or any sparkly effects of any kind at off-angles (except during the white field test above - and really had to look for it) during normal viewing. I tried some ambient lighting and the image held up nicely.

I need to do more testing. Anxious to try with the Panamorph http://www.avsforum.com/ubb/biggrin.gif and an HTPC, hopefully early January. That's it for now.


Carey P 12-22-2000 06:04 PM

Woops sorry!!! Just realized I've been saying BlackHawk instead of GreyHawk! I most humbly apologize. However, I'm not sure we are spelling Grey correctly either.


Dennis Erskine 12-23-2000 09:46 PM

There's not a lot I can add to the comments above. All my experiences with the GreyHawk have been with a JVC G11 (a G15 coming up). I am happy to see others noting the benefits of the THX microperf style screen I use in my designs. Some have also noted the care in packaging ... I'd have to add you'll be very hard pressed to find any company in any field that takes more care and pride in the production of their product and care of the customer following delivery.

I have found in subjective testing (inviting other dealers to view the results..one is a Stewart/Runco dealer, the other a DaLite/Seleco dealer) the following:

1) The greyness of the screen is not apparent until pointed out;
2) The shadow detail in films including the Messenger and Fifth Dimension are significantly improved. Frankly, unless one is very attuned to black level detail, I'd doubt one could perceive the differences in shadow details without seeing a CRT/StudioTek vs DILA/GreyHawk side by side.
3) There is no apparent loss of "white", or perceived shading of "white" as one would expect or fear when suggesting a "grey" screen.
4) There was no hot spotting nor color shifting. (Some slight impact at about 150 degrees).
5) Color reproduction is surprisingly vibrant (three dimensional may be an apt description.
6) Color uniformity is dead on across the entire screen surface (with the projectors noted above).

My own theater will be using a GreyHawk MicroPerf screen come January!

D. Erskine
DEsign Cinema Privee
Imagine what you could do, if you could do all you imagine.

[This message has been edited by Dennis Erskine (edited 12-23-2000).]

Phil Olson 12-26-2000 12:31 AM

I finally got my Grayhawk up for testing on Saturday and it does what you all have been saying, better black detail, great saturation, no hot spotting, etc. Definitely a winner! http://www.avsforum.com/ubb/smile.gif

However, I have a very different problem. My 100 X 54 micro-perf screen shows severe moire patterns from my G-11 D-ILA. http://www.avsforum.com/ubb/frown.gif

At 80" wide the interference lines are at ~1/2".
At 90" wide the interference lines are at ~1-3/4".
At 95" wide there is a null.
At 100" wide the interference lines are at ~1-1/4".
At 110" wide the interference lines are at ~1/2".
At 115" wide and up to full zoom there seems to be a null again.

Curiously, the interference lines only seem to be vertical, not horizontal. They are quite visible on light blue such as broad sky lines. Watching U-571 was really a great experience until the surface scenes where the sky had vertical light dark bands.

I know that defocusing slightly will negate the effect, but then one is stuck with a soft picture.

Can anyone else confirm this? I haven't received my ISCO II from AV Science yet, (any day now I hope), so that may be a factor. Also If you are all using a screen size above 115" wide it may not show. A 96" wide screen is close enough to a null that it also may not be apparent.

If I am doing something wrong please let me know, (though I really don't think so). May I have gotten the wrong perf type? The pattern seems to be a diamond shaped grid of .020" holes stagered .140" horizontally by .080 vertically, (perhaps why the moire is only prevalent on the vertical plane).

TIA, Phil

Edited to upgrade the hole pattern measurements.

[This message has been edited by Phil Olson (edited 12-26-2000).]

Dennis Erskine 12-26-2000 04:42 AM

That's a new one Phil. I've never seen that effect with the G11 on a MicroPerf...GreyHawk or otherwise. Have you tried to rotate the G11 a few tenths left or right?

D. Erskine
DEsign Cinema Privee
Imagine what you could do, if you could do all you imagine.

Mark Hunter 12-26-2000 07:52 AM

Tommy, Dean, Phil, Jeffrey, Carey & Dennis:

Without actually seeing the GreyHawk, it sounds from your reviews like it might not be quite grey enough.

Did any of you feel that you would have preferred even a slightly darker screen? Especially those of you with very bright projectors (>1000 lumens). Does Stewart offer a choice of "greyness" on the screens?


Mark Hunter

propeller_beach 12-26-2000 10:37 AM


In the end, you may not be the only one that sees it. It just may mean that no one else has had a chance to experiment with it because very few people have seen it yet. I don't think there have been too many GreyHawk perfs distributed yet. I thought I saw just a couple on the beta list that were getting perfs.

I am 150% interested in what transpires, as I am placing an order for a 96"Wx 54"H perf Greyhawk. I would be so depressing to have to deal with moire effects.


tommyboy2 12-26-2000 10:56 AM

No perf screen here so I can't comment on the moire probelm.

Mark, I really like the shade of gray (OK..can we settle on the spelling here...is it grey or gray?) they are using. My biggest gripe with other gray screens is that they are too dark. This one strikes the best balance in that you really don't lose much in whites and you gain a ton in shadow detail.


Dean McManis 12-26-2000 04:02 PM


I'm actually fine with the darkness of the screen now. I'm sure that you could go a bit darker with the screen material color, but it will start to give a poorer picture with larger or perforated screens, and older, less bright projectors which would limit the market more than the slight additional benefit in black level.


I have a larger screen, and I have the ISCO lens, so I'm probably much less likely to have potential problems with moire. The ISCO makes it very difficult to make out any pixel gap over 6 feet away, and the gray screen seems to hide it more than a flat white screen as well. But I'm not even getting any hints of moire, even varying the screen image size.

I'll remove the 16:9 lens and work with it tonight using varying screen sizes.

Did you try playing around with image positioning, tracking and phase controls yet?


propeller_beach 12-26-2000 04:48 PM

Dean, I am curious to find out. Please do tell. As always, you're my saveline.. http://www.avsforum.com/ubb/rolleyes.gif


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