AVS Forum banner

Status
Not open for further replies.
1 - 20 of 74 Posts

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #1 ·
Hi Everyone,


I realise this question may be best suited to the screen forum, but I wanted to address as many digital pj owners as possible in discussing this question.


On the face of it, reasons for purchasing the Firehawk are based on wringing out better blacks, shadow detail and vivid colour saturation from the current crop of HD1's and lower light output LCD's. Some owners have reported outstanding results with this type of screen.


However, I live in the UK and an electric tab tensioned Firehawk will cost the equivalent of $5500 US. This is a significant investment to say the least! Also, for how long will the Firehawk be of use? If the intention is to hang onto the pj 'Till death do us part' then Firehawk makes sense. However, if you are part of a community of enthusiasts dedicated to obtaining better and better images, then Firehawk begin to look like an expensive stopgap. My prediction is that in three to five years time we will start to see the introduction of hi-brightness true black digital projectors. Once these babies hit the dealers Firehawk will no longer be desirable. In fact it would hinder correct video reproduction. I mean, who on earth would use a Firehawk with that current true black projector, the CRT? Those of us dedicated to the upgrade path would probably have to ditch the Firehawk and purchase a brand new high quality white screen with a gain of unity. So why not just short circuit this expensive interlude? Go for a low gain white screen from the outset. It will provide sterling performance and will stand the pace of upgrade for alot longer than Firehawk.


As a postscript, the emphasis has been placed on obtaining better black level but little has been reported concerning compromised peek white. And compromise it must be. In spite of the gain on firehawk, the silvery gray quality of the screen will undoubtedly tone down and/or alter peek white compared to an equivalent white on a normal 1.3 gain. Is this an acceptable trade off especially when you factor in the questionable longevity of the Firehawk? Your thoughts on these perplexing matters would be greatly appreciated.


Best Wishes,


Paul H
 

·
Registered
Joined
·
755 Posts
The main advantage of the FireHawk is its ability to reject ambient and cross-reflected light, not the black level performance, so it should be well suited to high-contrast, high-brightness projectors.


The blacks look "darker" on a FireHawk because the image isn't washed out by ambient light. Even the best light controlled room with black floors, ceilings and walls will have some light from the screen bouncing around the room and washing out the image. The FireHawk is able to reject this off-axis light so the contrast ratio of the image more closely approachs the true contrast ratio of the projector.


Even if you had a digital projector with perfect blacks and an infinite contrast ratio, the FireHawk would still improve the image.


Cheers,

Dave.
 

·
Registered
Joined
·
4,718 Posts
Good point, but this begs the question, why buy anything now if you are going to have to replace it later?


Right now, the Firehawk allows me to have the largest possible screen with the current crop of DLP projectors. I am sure brightness will improve over time, but how long will it take, and how much will it improve?


I think it will be easier to turn down the brightness than it will be to increase it.


And yes, eventually I will probably have to upgrade my screen as I will have to upgrade all of my equipment. Such is the nature of this hobby :)
 

·
Registered
Joined
·
1,260 Posts
Wow, why so much? AVMall (sponsor link above) has a fixed 100" firehawk for $1299, and the electric greyhawk they have is just over $2000. [edit: so I'm drawing a conclusion from that that it shouldn't be THAT much more for an electric firehawk] Are they whacking you with that much tax??!!?
 

·
Registered
Joined
·
35 Posts
I have just put up my 92" Firehawk with my sharp 9000. I can't believe the picture. It is awesome!

I have a dedicated room with controlled light.

It was the best decision I made.

Be happy to discuss further with anyone.


Chris
 

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #6 ·
Hi David,


You make some excellent points and I know first hand the importance of minimising cross reflections to greatly improve contrast. However, I believe this screen compromises the purity of peak white because it is essentially still a 'gray' surface. Would not this also compromise the performance of a perfect black digital projector?


Phil, I can see you are a realist and I agree with you about the inevitablility of upgrading. I also think we are approaching the top of the calculus curve in terms of performance with these projectors. Imminent developments are likely to produce significantly smaller improvements than we have been used to: the law of diminishing returns. I suspect it will take a number of years before upgrading from HD1 to HD? will be worthwhile.


Best Wishes,


Paul H
 

·
Registered
Joined
·
2,099 Posts
Quote:
Originally posted by Paul Hayward
However, I live in the UK and an electric tab tensioned Firehawk will cost the equivalent of $5500 US.
Even if the firehawk gives you only three years of use, the electric tab tensioned frame could be used with any Stewart screen material. Your lose for throwing away the firehawk material is probably in the neighborhood of $1000, although I don't think the dream projector you describe will be around anytime soon.
 

·
Registered
Joined
·
2,091 Posts
I look at the screen as a longer term investment than the projector. I'm not sure that future projectors will be that much brighter than the current crop although I do believe contrast ratios will improve.
 

·
Registered
Joined
·
315 Posts
There is soooo much talk about how great the FireHawk screen is, and yet I am having a pickle of a time finding actual published data on the performance of the FireHawk screen. Stewart Screen puts a lot of effort in their marketing, but even they don't publish actual data. They just say "Its better".... hmmm This sounds awfully subjective, and I guess I'm not convinced subjective analysis is worth paying a premium for.


If I sound pessimistic, its because after hearing all these "glowing" reports on how wonderful the FireHawk screen is and how it is a must for DLP owners, I rushed over to High Fidelity in Austin, Texas to demo this "wonder drug" and frankly I left scratching my head. I didn't see any improvement in the picture between it, and the standard 1.3 gain screen they had on an adjacent wall.


If there has been, or will be any non-subjective analysis comparing the performance of the FireHawk to other types of screen material, could someone please let me know.


In the meantime, I am hoping Will, the owner of High Fidelity, wont mind me bringing in a sample of the Parkland PLAS-TEX to compare side-by-side it and the FireHawk. I would hope and pray (for Stewart's sake) that it would do a far better job with image quality than the $15 Parkland sheet, but if not, or the difference is nominal, then why would anyone even consider paying even $100 for one? I mean, at least with the Parkland, if you have kids and they do as my nephews do and hit the screen while trying to swat at the "carnivores" from the Disney DVD "Dinosaur", at least I'm not in fear of them scratching or getting dirty hands on a $2,000 screen. Instead, I just spray with 409 and wipe clean. Because of that, if fact, I hope the FireHawk doesn't blow away the Parkland because this will mean I'll have to either come up with a way of protecting the screen from idle hands, or constantly monitor the nephews when they are visiting and watching movies.
 

·
Registered
Joined
·
755 Posts
Paul, if the gray screen is a pure gray then it shouldn't affect the peak whites. Gray isn't a colour so it only reduces the brightness without changing the colour. The peak whites on a 1.35 gain screen should look identical regardless if the screen is white or gray.


That said, it's difficult to produce pure gray and the FireHawk has a very slight off-axis colour shift to blue. It's barely noticable.


Cheers,

Dave.
 

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #11 ·
Hallo David,


Many thanks for your information, its extremely helpful.


Hi Jonmx,


I didnt realise this was possible. Hmmmm. Looks like I'm really on course for a Firehawk demo.


Best Wishes,


Paul H
 

·
Registered
Joined
·
11,020 Posts
Paul Hayward:


Just to make sure you are aware of this, the price for all of the GENERALLY available Stewart screen materials is the same (at least here in the US). In the case of an electric screen you are usually paying more for the mechanicals than the screen material. As another member pointed out, you can always swap the screen material at a later date.


AustinTexas:


What specifications are you looking for that Stewart does not have on their web site?
 

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #13 ·
Thanks QQQ, I will bear it in mind when I demo the screen. There is one question that is still nagging away in back of my mind. If the Firehawk effect is to minimise cross reflections, then why arn't CRT owners flocking to take advantage of this valuable property as well?


Regards,


Paul H
 

·
Registered
Joined
·
2,091 Posts
There was a thread on the CRT forum asking exactly that question. What came out was that the Firehawk was designed for a single lens projector and a 3 gun would suffer from color shifting.
 

·
Registered
Joined
·
3,209 Posts
Projectors will get brighter in the future, but I don't think that having a screen with some gain will ever be a bad idea. As previously discussed, higher gain screens reject ambient light better than matte screens at the expense of viewing angle. Add a neutral density filter if you find the image to bright with your next projector. This will reduce the on-screen brightness and darken the blacks as well. When the lamp in your projector ages and dims you can remove the neutral density filter and enjoy a brighter image again.
 

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #16 ·
Hi John,


Yes I remember that thread and contributed to it. Didnt the three gun issue relate to high gain screens and the problem of the three colours being reflected back, a bit like a mirror. I thought the Firehawk was only about 1.35 which is in line with the recommendations of a 1.3 gain white screen for CRT. Maybe I'll go back and look closely at that thread. Thanks for bringing it up John.


Best Wishes,


Paul H
 

·
Registered
Joined
·
1,247 Posts
Discussion Starter · #17 ·
Hi, I've just been over to 'the other side' and checked out the 'Anyone using a Firehawk with their CRT' thread. The current wisdom seems to be that Firehawk was designed for all three colours to hit the screen surface at once from the same angle ie with a single lens projector. With CRT's they have three sources of light all at different angles and so the result is quite possibly a bit of a mess! Also, there may still be reflection problems because the Firehawk has an intrinsic gain of about 2 which is reduced to 1.35 because the gray quality of the screen eats light. Its reflective surface presumably still accentuates the colour shifting problem.


Regards,


Paul H
 

·
Registered
Joined
·
234 Posts
We made the product because people (many here), demanded it. It's a bit of a challenge to quantify the performance and we are working on this. When all we made was versions of white, we had to calculate available lumens distributed over a given square footage, express this in foot lamberts, take a look at the needed viewing cone, encourage a commitment to light control, and make a pretty straightforward call on the material. It's a new world now. There is a lot more available lumens on the average (CRT purists, quit reading here), and in the professional environment, folks are working, videoconferencing, what have you in a plethora of levels of ambient light. So there is a need for analysis of this ambient or incidental light. Beyond "how much" we need to look at "from what angle is it hitting the imaging surface". That is really important. Also really important is the contrast ratio of the imaging engine. We are trying to create a formula which will yield a shaded curve, or Venn diagram which would act as a guide for the applicability of the gray products. We are looking at the overall level of ambient light, it's angular distribution with reference to the screen plane, contrast ratio of the projector, brightness of the projector. We would like to distill this down to a simple go/no go, application chart. It's a difficult thing to do.

As many here have noted, ambient light has much more catastrophic impact on rendition of blacks and shadow detail, than the impact of a neutral gray tint on peak white. We would of course, like to provide a clear numerical rationale for those who are most comfortable in that realm. We are not there yet.

Mark Rejhon posted a lucid explanation a while back.
http://www.avsforum.com/avs-vb/showt...hreadid=131456

The addition of gray tint to screen fabrics used in certain ambient light conditions, will give us a measured contrast improvement of at least 25% in f.p. , and sometimes as much as 70% in rear screen applications. But at this time, the best I can do is encourage you to observe, using your chosen software, projector, and level of ambient light, and vote with your feet. Lots of people are quite satisfied with the cost/benefit of the decision for the time being.

People are using these fabrics to improve their daily enjoyment of the home theater experience, this week and probably for years to come. Of course there are better projectors coming down the pike, better meals, wines, cars, nothing new about that. Most people, however, don't change projectors like a revolving door. Bon Appetito!


Mark Robinson

Director of Operations

Stewart Filmscreen Corp
 

·
Registered
Joined
·
234 Posts
Here is a windows cut and paste of Mark's post which I just clumsily referenced. Mark R.

Originally posted by Mark Rejhon [/i]
This is right -- Stewart has a good split-screen demo on this. Left half and right half different screens, on the same projector. The contrast difference was quite obvious when there was ambient light!


This was also showcased at the AVSCIENCE party at CES 2002. So high-gain gray screens do enhance contrast by rejecting some ambient light while focussing reflected light outwards to the human eyes rather than evenly in all directions (as a matte screen would). This reduces reflections from the side walls as well.


Ambient light is fixed, regardless of whether the screen is displaying black or white. For example, turning on one small dimmable lamp in a room, ambient light could end up brightening a black by 1,000% while brightening white by only 1% for a 1000:1 contrast ratio projector. That kills a lot of contrast ratio -- about one order of magnitude loss of contrast ratio. Big impact on blacks and marginal impact on whites. Now, if the screen can reject some ambient light, the black would be brightened significantly less. Still marginal impact on whites. Thus, true measurable increased contrast ratio due to the screen material!


A gray screen with gain is ideal when some ambient light must exist or white walls ends up being used in a home theater. (Reflections on a bright image to the rooms' walls and back on the screen)


The gray makes the blacks appear darker in ambient light conditions. This equally darkens the whites, however. That's true.


The gain rejects off-axis light, and directs the light towards the viewer eyes, and reduces side reflections. This is what actually enhances contrast ratio. That's true too.


Aka high-gain gray, where gain would really be 0.4 or 0.5 if it was matte, but that the gain forces it to 0.8, or even 1.0 .... Pictured another way, the gray in the screen darkens the image (and the blacks, killing the effects of the ambient light) .... while the gain in the screen re-brightens the image while EXCLUDING the ambient light. Because the projector light is focussed towards the viewing area (a characteristic of gain -- retroreflectivity or mirror reflectivity property, depending on the screen). Ambient light or side reflections reflecting back to the screen itself, is rejected. (Typically, more than 50% ambient light is rejected in a high-gain gray screen) As a result -- contrast has improved on the same projector.


What is important is the whole picture -- the ambient light situation or the white walls situation. This is the type of situation where a high-gain gray screen performs wonders in truly actually enhancing sensor-measurable contrast ratio very noticeably closer to the projectors' specs. (AND perceived contrast ratios)


Of course, too much ambient light will always kill a screen, and a dark home theater is always better. But the bar is certainly raised...


The brighter the projector & the darker the gray screen (to compensate for the excess brightness), the better the contrast ratio will be during brighter ambient light situations.
[/quote]
 

·
Registered
Joined
·
196 Posts
I think it would be marvelous to have a Firehawk. But it is not worth it to me.


I bought a 5'x10' sheet of Formica from Home Depot (Special order - $78 - IceWhite) and trimmed about 3" off of one edge for a 120" 16x9 screen which absolutely ROCKS. I have white whites (not overdriven), and pretty black blacks. All colors are excellent.


Formica has a slight sheen, which on displays of one color give a hotspot in the center. I thought I might use an orbital sander, but then I realized that this would scatter the light, and therefore reflect more ambient to us. Not only that but it would be harder to clean, if sanded. (You know what I mean if you have kids) All official vendor screens have special coatings, which can NEVER be cleaned if you throw your beer at it.


My border is 3" baseboard with black felt glued on. I added wing and head curtains of navy blue velvet ($5.99/yd) for a total all-in cost for the screen and curtains of ~$250. Curtains are on a rod, so I can pull them in for 4:3. Rather professional looking.


I can view the picture from ANY angle, and it's not so affected by incident light due to the curtains. I have a room with light control.
 
1 - 20 of 74 Posts
Status
Not open for further replies.
Top