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Discussion Starter #1
There is a niche for simple off the shelf methods. Some people that come here and to other sites are looking for a DIY screen can quickly become inundated with so many methods ranging from advanced mixes to single sheet applications, to BOC, exotic fabrics and mirrors, and Acoustically Transparent materials. It stands to reason that most people just look and read, and the percentage of people that actually post or create threads is smaller than we tend to realize. I'm sure we lose some people because of the confusion and they end up going off and buying something commercial, which is a shame. Not that commercial screens are bad, it's a shame that DIY sometimes gets overlooked. Others are very interested, but still not sure which way to go

This is where the simple solutions are invaluable. They can get a new member up and running with an excellent screen for very little money while they research the different methods. Some people may never change their screen from a simple one can.

I try to keep the same format for all my threads. The first post is always an introduction and index, followed by posts that contain detailed information.

Here is the Neutral Gray and Simple Off The Shelf (OTS) index for this thread:

  1. Why Color Balance is Important
  2. The Whites
  3. The Grays
  4. Munsell Grays
  5. Selecting a Neutral Gray
  6. Gray Screen SW7071- Performance evaluation (Posts 7-10)
  7. Daylight Ambient Light Performance
  8. The Benefits of Neutral or a well Balanced Screen
  9. Lumen Chart
This thread isn't really a new topic, but it is a new way of looking at that topic. Before everyone went with the only thing they had available to evaluate something and that was their eyes. They would look at a color swatch and try to pick out the best looking gray. That's where the problem is though... it's not that we can't tell what is gray, rather since we were little kids we have been taught so see colors a little different than what the true color actually is. So when people were looking for a gray for a screen, they were looking at 'pleasing' colors, the ones they grew up being told were gray...

Take crayons for an example. That's one of the first way kids discover and learn colors. Gray is ugly... trust me on that one, from being in the military for over 13 years I learned to HATE gray and certain shades of green! Anyway, nobody would paint a room a real gray, it would look horrible. So the paint companies alter it some by adding blues or different pigments to get what everyone 'thinks' is gray and that way people will buy it.

We all know from shooting onto our walls that what looks nice on your wall doesn't mean it's going to make a good screen. Sometimes it may, but the odds are it won't.

So I started this research because people are always looking for a neutral gray, and saying there are none you can buy so 'we must make one'... well the GTI Munsell N8 IS neutral, and although some of the colors I will talk about are not completely neutral, they are very close (closer than any of the off the shelf grays I have been seeing people use and recommend) and will work for our purposes.

Now the problem is to get people to accept them. I actually told people about the GTI gray RP Imaging sells a long time ago, and after I found it, I discovered others had already run across it, but at $80 a gallon it was more than people wanted to spend. The paints I matched through the database are not $80 a gallon, so there are some very good options out there, and I even have some tips about the GTI N8!
 

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Discussion Starter #2
Why Color Balance is Important

This is going to be long, just a warning.

A Home Theater that is comprised of a front projector has many components and variables that ultimately determine the overall performance. Some items and elements we can control, like the projector's color balance, brightness, contrast, gama settings and so on... and then there are other items that are harder to control or in some cases impossible, such as sunlight, room layout, etc. We really shouldn't be using the screen as an 'adjustment', only if there is a reason to do that. The color balance of a screen may be one of the most critical items in an entire home theater setup. If the screen skews the colors of the projected image, it is not a very good screen. Ideally we want a screen that reflects the projected image the most accurately and efficiently- accuracy for the image color, and efficiency for the overall brightness.

White screens are the easiest and most forgiving, but even they need to have a good color balance or it can shift the projected image's color.

There always seems to be an ongoing debate about gray. Either about its ambient properties, or that it takes more than gray to make an ambient light screen, or it kills whites and makes images look muddy… to it is the best type of screen a person could have. So who’s right and who’s wrong? Everybody and nobody.

A lot depends on a person’s personal tastes and what they like. Gray undeniably helps with black levels and perceived contrast for projectors with less than stellar contrast ratios. It is also better with lighting in a room and can deal with ambient light better than a white screen can. I still do not feel this makes it a true ambient light screen, but as stated by others I agree it is better than a white screen and more appropriately should be called 'ambient light friendly'.

The debate about grays is still roaring on. I find it interesting that for the most part everyone is saying the same thing but arguing different points. To me the debate breaks down to not whether gray is good or bad, but what gray and shade should be used. Some have even said that grays are a passing thing and back in 2003 it was said by one person that
Grey screens as you may recall were introduced at least in a large part, to enhance the sorry CR most digital projectors suffer from. That's changing. The low CR high lumen projectors of yesterday are giving way to designs much more suited for home theater.

I feel a member of your talents is spending a great deal of time and effort on something that will be behind us in a year or two. Let's face it, no one would had ever given grey so much a thought if the blacks looked right on white screens. Ever been to a film cinema where they project on a grey screen?
What I'm saying in a nutshell: grey is a dying horse. I would enjoy seeing your talents focus elsewhere. Even I, one time defender of the grey, ME in particular, see the handwriting on the wall. Thanks for listening.
(This was not a quote towards me since my talents are limited ;))

Hence the saying ‘Never say never’, and dealing with absolutes is always a touchy area as well. It is now the middle of 2007; over three years after that statement and grays are still very much in demand. Commercial screen companies have not dropped them; in fact they have increased the number of gray screens as well as enhanced their performance. The big question though is WHICH gray?

I find it interesting that neutral gray is viewed by some as the Holy Grail of gray screens. This has been debated for a long time now. Some have gone back and forth in this debate, stating neutral is the way to go and then later questioning why the importance of a neutral. I have questioned this myself since manufactured screens are not completely neutral. (All new readings are in the process of being done, but the discovery of the 'V' curve was deemed a valid by RIT and color scientists, so I feel confident with keeping the 'V' curve a valid option) If you look at the color curve once the spectrophotometer values are converted to RGB, most have a distinctive ‘V’ curve. So the question is why would they do this? Here are some explanations I got:

1. They did it on purpose- so the screen will look good even if the projector is off a little. A red or blue push doesn’t look too bad, but a green push kills skin tone- and this is how many people judge image quality.

2. They did it accidentally- when gray came into popularity, they just used the most common standard, which is illuminant C (6774K). Many commercial grays are almost exactly on for illuminant C, but there are some that are not…

3. They did it ‘cause their cheap- Variation is much less important this way and pigments aren’t as critical.

Here is what those pushes can look like as compared to the correct image.
Correct Color

Red Push

Green Push

Blue Push

Red is the most acceptable and forgiving to a point. Some people actually prefer a cooler image, so they may not mind a blue push, but green is definitely a bad thing to have any type of push in. Seeing that some Director's and Director's of Photography film with a blue tint (check out the Terminator movies sometime, especially T2, it has a distinct blue tone to it) a screen that already pushes blue would certainly take the movie image over the top and beyond what the Director intended it to look like. In some cases to a point that is unwatchable to some people.

Hopefully the reason why screen color balance is so crucial is starting to make sense.

So I asked the question if commercial screen companies aren’t concerned about their gray’s being neutral, should we? That’s like the opening statement about who’s right and who’s wrong… yes we should be concerned, yet no we shouldn’t… but both of those answers have a reason in my opinion.

If we look at what I call the ‘V’ curve for many commercial screens, we see they are green deficient, but usually the red and blue components are relatively balanced. There are instances where there is a slight blue push, or a slight red one, (or a slight deficiency). A ‘slight’ push in either of these colors can actually be beneficial in some instances. A slight red deficiency could help some with incandescent lighting since it leans in that direction, while a slight blue push can make whites appear ‘whiter’ (another color conditioning we all have had since we were born). The trick and key is knowing when the push is too much.
Note: The original readings were based on the C Illuminant, new readings based on D65 are currently being done. The 'V' curve concept is still a valid one though but as related to D65 not C.

A few years ago DIY was dealing with these questions and ideas, but for the most part there was no data. The spectrophotometer tests that have been done recently, as well as the converting of that data to RGB values has done a lot in the way of understanding commercial screens as well as now knowing the color composition of DIY methods. RGB is widely debated by some as being useless when discussing screens. I disagree. It’s hard for the average person to understand CIE data and looking at those numbers isn’t easy for someone not used to what they mean to determine if a color is pushing to hard one way or another. RGB makes it easy to quickly see the color curve. If the ‘V’ is in line with typical commercial screens, then yes that color would most likely make a nice screen- as long as the color itself isn’t some wild off the wall color. If it is a white or gray then I would have no problem using it as a screen.

So I just completely contradicted myself when it comes to neutral grays? Not really. Even though it was just stated and shown that commercial screens tend to have a slight green deficiency, that doesn’t mean a neutral color is bad… just that the commercial companies strive for the best image across the widest range of projectors AND consumers tastes. As stated earlier, green can push hard even with the slightest increase in RGB value. Most people only do basic calibrations. This way the commercial screen looks good out of the box to most users and projectors.

Seeing color is a sensation, like hearing, taste, or smell. Sensations are not felt the same way by every person. Food tastes differently to each person. In the same way, there is no absolute color that is inherently seen the same way by every person. Nor is every person’s vision the same. This is where neutrals come into play.

Neutral gray will eliminate/reduce color contamination from reflected light. Even though slight variances in screen composition and colors will work fine, a neutral palate is the best at reflecting the colors back the most accurately.

Also different light sources affect the colors that you see. For instance, a color viewed under fluorescent light will look radically different when viewed under incandescent light. Fluorescent light adds green to colors while incandescent light adds red. (This is why a slight red deficiency in screen color can be helpful with incandescent lighting)

[PIE]A front projection Home Theater system consists of several devices that all deal with color at some level, and in different ways. Projectors deal with colors being created by light, and the screen deals with colors being reflected by pigments. Because all of these components in the system handle color in different ways, color reproduction between them is not so obvious. They use different color models, have different color gamuts and different Gammas. Moreover their colors are influenced by calibration settings and environment. Again neutral colored screens reflect the light from the projector with the least amount of color skewing.[/PIE]

What really sold me was when I went from a bright white screen like Designer White to the SW 7071 Gray Screen. In the quick setup I did I found that the more neutral the gray, the less color adjustment is needed. In my case and with my quick setup I did not touch the color settings at all between the two screen colors, only the brightness and contrast levels. The picture was even better after a full calibration, but my point is with other grays I DID have to make some drastic adjustments to the color.

I am not abandoning any previous research and testing I have done. I think both can coexist… as long as the ‘V’ curve isn’t radically pushed by the red or blue components it will work just fine. Neutral grays however will allow us to go darker with fewer color problems than if the gray is not neutral and meant to be an aesthetically pleasing color as a wall paint. Also a neutral color reflects light the most efficently, therefore the image tends to be brighter even with darker shades of gray.

Many people have been searching for neutral grays for a long time now. It’s not that they didn’t know what they were looking for; it has more to do with technology and more readily available data. Now we can actually see spectro data and the RGB breakdown of colors where a couple of years ago that type of data didn’t exist in the DIY realm, at least not from what I have seen. Now that we found neutral grays, it’s kind of ironic that the discussion by some is pulling away from them and suggesting non-neutrals. Both will definitely work, and like I said earlier, everyone’s tastes are different. I think one benefit of a neutral gray besides allowing us to explore darker shades, is that since the color skew is at its minimum; once the screen is calibrated it stands a better chance of being pleasing to a wider group of people. I know when I finally found a ‘compromise’ with one gray paint I used, it still wasn’t optimal. Even though I probably could have gotten used to the color shift, anyone else walking in for the first time would most likely see it was off since they were not ‘adjusted’ to the screen themselves. To me that is a bad screen. People should not be told ‘Well you’ll get used to it…’ there should be no reason to.

I’d like to think what I just wrote will not be taken as anything personal by anyone since it was not meant that way. I have done a lot of research into colors and specifically grays. These are my findings and how I feel about gray for projector screens… I am by no means saying this thread is the definitive thread about neutral grays, or that everyone should drop what they have now in favor of them. I do however feel that neutrals have been found, and they do perform very well.
 

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Discussion Starter #3
The Whites

Whites
I know I said this thread is about grays, but white is important to some people too, and this will only be a small section of this thread.

Matte white is a benchmark... a matte surface with a gain of 1.0... You'll get a good picture, but also know it can be better in some situations. I am not just saying white is used as a benchmark and you are supposed to just believe me, I actually called the engineers at Mitsubishi, Panasonic, and Sharp. They all use a plain jane unity gain (1.0) white reference screen when they test and QA their projectors.

The best way to determine what screen will work and provide an optimal image is to get a baseline. Kilz2 is a very easy and nice unity gain white screen that anyone can put up quickly. Since this thread is dealing with painted options, most will want to use a primer first, so why not take some time to do an initial calibration? If you use Kilz2 as the primer coat, you already have a nice reference screen right there, so why not use it?

UPW
People have used a lot of different whites, the most common one everyone will see in here is Behr Ultra Pure White, called UPW for short. UPW is a very nice white with a RGB break down of 253 244 253 (numbers being reverified). To try and put that in a mental perspective, a StudioTek 130 breaks down to 250 241 249, so it's close to that shade of white. Is it as good as a ST130? Go back to what I said earlier about what to expect from a $10-12 can of paint... but it is a very excellent starter white screen.

UPW is used as a base for some advanced mixes too, so it's a nice starting point for some.

Rosco Off Broadway White, and Rosco White White
Rosco paints are a little blast from the past. I am unsure why it lost a following, perhaps because it's not as easy to find as UPW, but it can be ordered online, and Rosco also has a store locator. I was surprised to find a store 17 miles away that carried it.

True Value Luminous White
This is a new one added to the white screen list. It is a vinyl polymer as compared to latex. It also has Titanium Doixide as well as Calcium Carbonate and mica included. This is just as bright as UPW and may even exceed its performance. More testing is to come on this very unique and readily available white base.

Kilz2
Yes it is a primer, and me personally, I always prime first. (Unless you plan on an advanced paint mix application, if so follow their instructions)

When applied it has a smooth flat look that surprisingly does make for a very nice temporary screen! This could be a very good first step for someone unsure which way to go since you'll already have a primer coat down. If the advanced mix calls for a substrate or no primer, again follow their directions, but you certainly won't be out of the game. Keep in mind this is a primer and a flat paint, and as such flat paints do not like any kind of dirt, and are not very friendly to clean. The plus side is, you can always throw another coat on.

Unlike Rosco paints and UPW you can get Kilz2 almost anywhere. I picked up a gallon of it at Walmart for around $13. Why a gallon? I am remodeling a 143 year old Victorian house and like I mentioned, I always prime first, so I know I will be using it for other things as well. A lot of people may even have some at home already.

So there are three very nice whites to get people up and running with a nice matte white screen. Rosco's Off Broadway White White is not just a temporary screen, it is an outstanding white screen that many will be more than pleased with and will probably never change... unless they want a gray for ambient viewing and to bring out the black levels more.
 

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Discussion Starter #4
The Grays

Grays
So what’s the big deal with a gray screen anyway? Well they help boost perceived contrast for projectors with low contrast ratios, they make blacks appear ‘black’ or blacker, and they fair better in ambient light than white does.

Just because it’s gray though doesn’t mean it’s an ambient light screen and all your worries are gone. And not just any gray will do, too dark and a projected image can look dull and muddy, too light and the advantages with ambient light are reduced or negated. The advance DIY mixes and commercial gray screen paints literally have years of development and tweaking with the components. Many of them also employ a poly to the mix to add gain and depth to the image.

People are always looking for a simple gray though. The same reasons apply… maybe they don’t have a lot of money right now to spend on advanced formulas, or maybe they haven’t decided which way they want to go, but they do know they like some lights on from time to time and they want a gray.

Same disclaimer as before…there are already several off the shelf grays being used. This thread isn’t to cover topics that have already been discussed or have ample information already.

The main drive and goal with grays has always been to find one as neutral as possible. In fact a lot of the advanced mixes have this as one of their primary goals. Why neutral? That way the painted screen will not have a color shift one way or another.

A little background
Alfred Munsell was a color theorist who published a book called "A Grammar of Color" back in the 1920’s. Munsell's system was based on color as it relates to light; this was different because it dealt with how we perceive colors and not how they are physically made with paints. If anyone is interested, here is a link to a nice article on the Munsell system.

So what Munsell came up with was a system that has been used for over 80 years now. The grays in the Munsell system are neutral grays, so I decided that was the place to start.

What is so special about Munsell Gray? Well to start, Munsell isn’t paint, it’s a color system. Below is the Munsell gray scale.


Since there are already grays being used, and mixes trying to develop a true neutral gray, I decided to look for off the shelf grays that also had data as to how neutral they really are. That turned out to be no small task, but I did find a company called RP Imaging that sells a neutral gray paint Munsell N8/ gray as specified by ISO 3664:2000.

I believe the reason why there hasn’t been much written on as a DIY screen is because at $68 a gallon plus $12 shipping that is more than most people want to spend. Plus most of the people working on mixes and one can solutions strive to find something that is easy for the average person to find.

Well here is a neutral gray. It may be a little dark, but not much darker than SS or some of the other mixes I've seen, and the testing coming up will show neutrals perform exceptionally well.

Munsell N8


Munsell N9




Addtion by cynical2 (12/31/2007):
This thread seems to be a good place to post the scale with the respective RGB values and shades. The color swatches were captured after calibrating my monitor, but keep in mind the exact shade you see is going to be monitor dependent. However, this should give a good idea of the gradations. It becomes fairly obvious why, for pj screens, you never hear us talking about anything below about Munsell N7. Below that and things are getting quite dark.


 

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Discussion Starter #5
Munsell Grays

Munsell Paint Matches

I couldn't find anyone that sells the GTI Munsell N8 paint other than RP Imaging... however I did find out that GTI is located in Newburgh NY which is around an hour and a half away... I have a military buddy that lives down there so sounds like a visit and field trip!

Here is how I approached this as far as neutral grays. A lot of time and money has been spent by people trying to develop a neutral gray. GTI has one already, but it also may be more than what some want to pay, although I still feel it's not that much. I went through the database of all cataloged brands of paints and did comparisons to Munsell N8 and N9 and I found some matches that are very close... as close as we're going to get from a premix.

The following color matches have the Munsell color in the center and it is surrounded by the closest matches. To the left is a quick color summary of the Munsell color, then at the bottom is the closest matching color from that manufacturer along with a quick color summary of that color. If anyone wants to see more detailed spectrophotometer data on any of the colors let me know and I can post that.

Here we go...

Munsell N8 will be first since we know RP Imaging sells paint in this color and we now know who makes it.

Munsell N8/Dunn Edwards


Munsell N8/Martin Senour


Munsell N8/Sherwin Williams


Munsell N8/True Value



Next are some close matches to Munsell N9

Munsell N9/Brunning Paint


Munsell N9/Caparol


Munsell N9/Colortrend (Take a close look at this one... this needs some further data for certain)


Munsell N9/Dunn Edwards


Munsell N9/McCormick (Here is another one that deserves a closer look)


Munsell N9/Sherwin Williams


So as we see, there are numerous grays that are very close to our D65 neutral reference point. Next we need to narrow things down to a more manageable list of manufacturers and colors. I provided all known matches though because you never know if someone has a local store that sells a particular brand of paint. For instance I don't have any stores that sell Martin Senior paints near me, but someone else may have one in their home town... and there is a very nice looking N8 match that Martin Senior has, so I didn't want to make this a one brand or company specfic list.

There are two other companies but one looks like it is automotive paint, and I couldn't find anything on the other... they are Sikkens, and Sico. If anyone is familiar with either of these brands let me know and we can get some color analysis to cross check the above values.
 

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Discussion Starter #6
Narrowing the Playing Field

A while back I had a thread going elsewhere about screen color matching with a very interesting discussion about colors. Here is a chart gives a nice visual representation of what the colors look like and how they compare to each other and also has the RGB values.


I took the RGB values and plotted them on a graph. I like the graph in addition to the swatch chart because I can see the order from light to dark, plus when graphed you can see the color curve better. We always look for a neutral color, but it is interesting to see a lot of commercial screens are slightly green deficient.


What I did next was look at the local paint stores that were close to me. There are a couple of Lowes and Home Depots, but unfortunately Behr, Glidden, or Valspar are not included in the database so I didn't have any matches for what Lowes or Home Depot sells. There is a True Value right in my home town, and over in Bennington VT (a short 9 miles away!) there is a Sherwin Williams store.

So I narrowed things for a nice Munsell N8 match to either Winter Mountain from True Value with an RGB value of 200 201 201, or Sherwin Williams Gray Screen which comes it at 199 203 203.

I ended up going with Gray Screen SW7071 for my first test. The reason why is it comes in a very durable matte finish, and Winter Mountain only comes in the flat finish. Flat paints are okay, but they are not very easy to clean, and flat paint can get dirty or smudge very easily. Also matte is the same surface that commercial screens have, so I was intrigued with Sherwin Williams.

When I walked through the door, there was a display for the Duration brand in the matte finish. One panel was painted with a flat white, the other with the Duration matte white. There were markers there and the display encouraged you to draw on both panels... which I did :) Then I took the spray bottle and sprayed water on each panel... the marker drawing on the Duration matte finish actual started to come off just by being hit with the water. A quick whip with a paper towel they had there and it came completely off while the flat paint panel remained marked up. I was sold! Anyone that knows me and the extensive torture testing I did with the laminates knows I like a tough and durable screen, and for a painted screen this is pretty durable stuff.
 

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Discussion Starter #7
Sherwin Williams Gray Screen- SW7071

I got some Gray Screen-- SW 7071 in the matte finish.

I have found out that Sherwin Williams has two matte bases. For anyone that wants to go this route, the one to get is Duration Home, Extra White Matte Base, 6403-63925. The BAC code should be
BAC Colorant 02 32 64 128
B1-Black - 20 1 -
Y3-Deep Gold - 5 - 1

Insist they use the base and BAC listed above. Someone went to Sherwin William and they used a different base (cashmere) and it had a different BAC. The colors were pretty close, but they did not perform anything alike, so I wanted to bring this up to prevent anyone else from running into the same problem.

The container is actually pretty cool. It's a plastic container with a screw off top and a built in handle. There is also a pouring 'spout' that helps keep everything nice and clean when pouring it into the roller tray. Sherwin William is open Sundays for people that tend to work six days a week like I often end up doing...

Now for the bad news, well maybe not bad but not so good... First it only comes by the gallon. That's enough for at least four screens, so there is always the option of splitting the cost with someone, or a few someone's. Price-- It's $40 a gallon. Not really bad considering it's the only neutral matte gray paint I have found that you can clean very easily. So that still only comes out to $10 a quart, which isn't bad. I couldn't help thinking though that for a little bit more I could have ordered the GTI Munsell N8, but I wanted to give this a try since it is something everyone should be able to get very easily.

I have some polyacrylic as well as a clear matte finish that I am going to test a few things out.

As far as I know I was the first person to try this as a screen. With a name like Gray Screen, I am sure it has been used by people just as Silver Screen has a catchy name and caught people's attention.

Here are the first shots. Now, keep in mind the paint is still wet and looks blotchy because it's starting to dry and some areas are still wet. Also this is the first coat. After it dries I may hit it lightly with a 3M sanding sponge, I'll have to see if there is any imperfections when it's fully dry.

This is a shot with the first coat on, still drying as I mentioned. The paint looks pretty light in the container, but when I started putting it up it is the darkest gray I have used to date.


The next shot isn't anything fancy as far as a screen image or test pattern or anything like that. It's just the HD931's welcome screen. This is at 2:45 PM and I have tons of light issues during the day as anyone that knows me is aware.


Just for comparisons, I pulled the picture of the initial screen size test on just the liner paper.


This one is from the doorway to the room. You can see the one window to the right of the screen, and to the left is a bay window that is around 6' wide and the windows themselves are a little over 6' high... lots of windows and light problems. I put the menu up to see if I could even read it during the day...​


This one is from the doorway with the welcome screen up.

Here is a comparison shot on just the liner paper from the same angle. Both of these shots were around the same time of day so they are similar settings.

Like I said and I want to emphasize... this is the first coat and the screen is still wet so these are not going to be very good representations of what it will look like when it has a couple of good coats up and it's totally dry. (If anyone is curious, my temporary border is nothing more than 3M painter's tape... I looked for black hockey tape but couldn't find any...)

I did a real quick basic calibration. These initial screen images where taken with the camera set to auto and no tripod was used, so if some look a little out of focus it was me moving and I can assure everyone that the image on the screen was perfectly in focus and clear.

What looks like distortion in the bottom right blue square is a watermark THX calibration statement.
Quick note: One of the calibrations in the above screen is to make sure that the blue boxes in the lower left of the screen are two distinct shades of blue. When I was using SS, I could not get the boxes to look different shades. This time before I even started the quick calibration the blues were different shades. Actually, I didn't have to make many adjustments at all from my previous setting, but again this was a real quick 3-5 minute rough calibration.



Straight on


From the door
... nothing was edited in any of the pictures, not even to resize them.
 

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Discussion Starter #8
After three coats and a week of curing...

Okay here are some more pictures now that the screen has had a solid week to dry. I made a quick border for it as well (my DW screen was just tacked up, I am working on a frame where I can load test panels and am still designing that one). The border actually turned out very nice for a total cost of $21.

To start here are a couple of shots with the screen now 'dressed' with a temp. border. I started taking pictures around 2:30PM. I took this from the doorway to my second living room looking in from the hallway, that way I could include a window to give an idea of what time of day it is and the brightness in the room.

The first set of pictures are some color bars and gradient bars. It is still the same time of day, but the camera is making it look darker in the room. These pictures were taken within minutes of the first one, so there has been no change in the light from outside coming into the room. In fact I actually opened the blinds to try and make it brighter in the room.


Same color bar, but from the doorway leading to the second living room. I intentionally included the window to show how much light is coming in.


This is from the second living room at approximately a 45 degree angle and around 22 feet away.


Here is a gradient scale, same time of day.


From the doorway with showing the window.

...and from the second living room... in this shot you can see one of the far right windows of the bay window. This is really the angle that kills my screen. The light coming in is very close to the screen and 'glances' off the screen at a 50-70 degree angle. As it can be seen from this picture, there are no problems with brightness from this screen at this time of day.

The good ole Dolby Digital logo (it's off center because I didn't wait and paused too soon). I actually turned on my 36" CRT set for this picture to try to give an idea of brightness as compared to a normal TV.

Before taking any movie shots, this time I am going to change my gamma setting ON THE PROJECTOR. I do not see in anyway how that can be manipulating the screen image since it falls more in line with projector calibration.
 

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Discussion Starter #9
Performance shots

I did a recalibration and reshot some scenes. My camera is set to Auto with the exception of white balance, I set that to the natural light setting. Auto White balance made everything come out blue and the screen definitely did not have a blue hue to it.

First is the Columbia Logo, I just like the colors and how rich they look.


Sin City... I loved the way Rodriguez filmed this movie.


...Goldie (Keep in mind this is a darker gray-- you can still make out details like wisps of hair.)


Charlies Angles Full Throttle. This is a horrible movie, but when McG didn't over saturate everything there was some nice eye candy. I got this as part of a double disc along with Into the Blue... I'll be taking some shots from that movie this afternoon.


Conan






Akira
 

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Discussion Starter #10
Additional Performance Shots

The Fifth Element has become a staple of screen shots, so I took a few from that movie.

The Fifth Element




The Jump scene


Jump scene from the door to the hallway


Jump scene approximately 45 degrees off angle from the adjacent living room. There is no major viewing drop off that I can tell.


One more classic shot...

Next will be a different variety of movies to get a feel for different scenes and colors as well as some animated shots. In an earlier post I did a couple shots from T2 and one from a low quality $4.88 DVD called Chances Are, so I am trying to put up a mixture of things.
 

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Discussion Starter #11 (Edited)
Keep in mind my projector is a 6 and 1/2 year old factor refurbished business projector, not a projector specifically made for HT. I have issues with it, like jaggies with text, and things like that... but if my pj can look this nice with this screen, then I am slobbering over the idea of when I upgrade to a full 1080p HT projector.

I spent six hours in this next round going through various DVDs and taking screen shots. It is a lot more work doing screenies than people think ;) Sometimes I think it's faster and easy to make the screen than backing up its performance.

I honestly think that within the next two years we will be seeing live video screenies instead of still shots. Then people will be able to see the actual performance of the screens. I see so many things that just do not come out on picture the way they look on the screen. I tend to compare my projector to my 36 inch Toshiba (you can tell this was archived and transposed from elsewhere since I now have a 55" 1080p SXRD set), and right now I like the projector better for movies. It is bright and vibrant, but it is more film like, and to me as a movie buff I love that. I have to give the edge to the CRT, the colors are better and much more vivid, but compared to film and my current screen, to me they look over saturated and loud. HT means different things to different people. Some want a HUGE TV... super bright, over saturated... me... I love movies. I do want to see my colors right and the images bright, but I also want them to look like a movie and not a video. Does that make sense and hit home with anyone else?

Who knows though, they are playing with laser projector technology now, and when that comes out we could project an image on a cinder block and it would look good. I don't shun those days though, I look forward to them. Think of the exciting things that we can do when that day comes... as well as the people that have older projectors, DIY keeps getting better and better and is a long cry from the days of bed sheets and window blinds. We've actually reached the performance of mid to high end screen with the advanced options, and the data is showing that the simple methods are far exceeding some of the entry to mid level commercial screens.
 

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Discussion Starter #12
Daylight Ambient Light Performance

Ambient light has always been a problem with front projectors. Room lighting is bad enough to wash out the image on some screens, but sun light is the ultimate screen killer. I am cautious about calling this an 'ambient light' screen since I think that term is thrown around way too much by some people. The companies like Planar, DNP, and HoloVega all spend millions on research and development for their ambient light screens, and they pass that expense on by way of the price we have to pay for those screens. So DIY screens and other screen paints certainly are not true ambient light screens in the sense of a SuperNova, but at a fraction of the cost they perform very respectably. I like to use the term 'ambient light friendly'. :)

Okay here are some more day shots. I started taking these around 1:30PM. It was winter when I took these and I lose daylight early during the winter and that time of day has the same amount of light in the room that I normally have during the summer around 3:00PM.

The room is very bright right now, and with sunlight not incandescent lighting. This is where most screens really bite the dust, and performance for Gray Screen did take a huge hit with this amount of sun pouring in.

Here is the Warner Brother's logo showing the window next to the screen and how bright it is right when this was taken.


From the adjacent living room showing one window of the bay window to the other side of the screen.


The DVD main menu


The boys on their way to Vegas...


From the hall showing the window again and the amount of room light.


The boys all dressed up and ready to roll.


Same shot but from the adjacent living room.

I ended up getting called for a work problem and had to stop taking screen shots for about an hour. It was probably a little after 3:00PM when I resumed. The room was starting to get dark, more the gray over cast look of early evening. The sun had moved and wasn't lighting the room as brightly as before. The screen started performing much better.

Costner in action.


Costner's 45s

Same shot but from the adjacent living room. These are the windows I have the window film on and they do help, but this will give an idea of the light level. I am thinking about putting some film on the outside of the window too. That should cut the light down so that around noon it will be this level.

I think these shots show full daylight performance (or lack of) very well. Like I said, this isn't an ambient light screen, and I never said it was, but it does perform respectfully for such a simple method. It is definitely watchable with the light levels when I first started, but honestly even after I resumed screen shots, to me I would never watch a movie in that bright of conditions. On weekends during the day, if I watch a movie I normally watch it on the 27" LCD HDTV in the bedroom. With a little light control and using BOC as actual drape liners and not as a screen this would be quite usable during the day for anyone interested in a simple and relatively inexpensive screen application.
 

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Discussion Starter #13
Evening Performance Shots

Earlier were some daytime shots, here are some evening shots. These were taken around 4:30-5:00 PM.

Top Gun


Top Gun the VBall game... my wife loves this scene so I figured why not take a few shots for any of the gals out there, they like eye candy too =]


Incase anyone wants to know, this is Rick Rossovich. He's probably wondering what happened to his career too! But at least he's immortalized in a scene I think every women back in '86 saw over and over again...


...and his Vball partner and pilot, a little know actor at the time by the name of Val Kilmer...


Top Gun Graduation... I will get around to some comparison shots with other material, but I saw these and wanted to put them up. White is definitely white which is still amazing me seeing this is a darker gray.


From the hall...


Off center from the adjacent living room...
 

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Discussion Starter #14
The reason I took so many was so I can try to show a wide variety of material. I'm trying to show light scenes as well as dark scenes along with scenes with a lot of color.

The Columbia logo shot I put up earlier still makes me smile. For a business projector I was very pleased with its performance. The logo really is that deep and rich in its colors.

Here's a couple from Star Wars, a James Bond flick (from the opening scene in Tomorrow Never Dies, the best Bond opening teaser ever), and one from Into the Blue.
I started getting tired so I only grabbed a few shots even though there are so many good ones to choose from. Star Wars and Into the Blue are definitely full of eye candy and colorful scenes. My brother suggested some Bond ones so I threw in TND.


Star Wars Revenge of the Sith:
The star cruiser is dark on the screen too, but I can make out much more detail than what is picked up by the camera.




One from Into the Blue


Same scene but off center and from the adjacent living room.


The name is Bond, James Bond... Like I said, these are from the best opening sequence of any Bond flick to date.

Brosnan as Bond and getting ready to take out the weapons bazaar.


Bond doing what Bond does best, well maybe second best...


England's Top Gun...
 

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The benefits of neutrals and a well balanced screen are very important factors. The more accurate the screen is at reproducing the image being projected the easier it is all around.

As we have seen and has been demonstrated and proven in other threads (and I also have seen first hand) there are benefits to the classic 'V' curve that the commercial screens have. Green pushes the hardest of the three color components. I would say that projectors can be calibrated and adjusted for a rather large divergence from a perfectly neutral screen but we certainly aren't wrong for starting with something that reflects color as accurately as possible. If anything I would go with a slight green deficiency, but keep in mind-- when we say a certain screen or color is deficient one color, it is not just that color alone. The whole screen's color spectrum is shifted somewhat. For the most part it's not that much, but it does have an overall impact on the image.

The same thing applies when we change the temperature setting on the projector from warm to cool. Warm is adding red to the overall image, cool adds blue. It's the same thing with a deficiency or push. Green is the worse because we may be able to adjust the color setting, but unlike red and blue, there is no overall 'temperature' control for green.

Here are the examples again of what the various color pushes can look like. From left to right are: The correct image, a Red Push, a Green Push, and last what a Blue Push looks like. These are pretty extreme, but they get the point across nicely.


I have never felt that the screen should be where the image gets adjusted. The only exception would be for extreme videophiles that want to perfectly mate a screen to their particular projector to get the absolute best image conceivably possible-- for that specific projector/screen combination... I'm sure most have heard people mention diminishing gains, doing tweaks at this extreme level is eeking out 1%, maybe even less. Most people probably won't notice, or want to go to this level of work... but for some it is well worth it to them. This isn't as easy as it sounds though. You would have to have measurements of your exact projector output levels, and then very precise measurements as far as screen construction.

This is very different than the tweaks people are doing in the advanced mixes for making a well balanced screen color that works well across a wide range of projectors, and I don't want it to sound like that is what I was talking about. I see the previous statement like the audiophiles that put drop mikes throughout the room and take sound pressure readings, use signal generators, and other high end tweaks.
 

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Lumens

Here is a good lumen guide. As with anything, it is just a guide and different setups and projectors may have slightly different capabilities.


In the past there were few actual Home Theater projectors, at least in the price range that the common person could afford, so many people went with used, refurbished, or less expensive presentation projectors. They do tend to be brighter, but don't go solely on the lumen ratings. They were made and used for data presentations such as Power Point and other typical conference room software. When used for video the lumen output does drop, but they are still bright units (most of them).

Like my conversation with the projector manufacturers mentioned in an earlier post, we have to keep a few things in mind when looking at charts and things like this, like what was the reference being used? In this case it was again a unity gain white screen rating. Based on that, there is room for some improvements with a screen that is more ambient light friendly, but the chart is still a good guide line.

I plan on reworking the chart and adding shade recommendations based on the lumen levels and screen sizes.

To make things even more confusing, some manufacturers are now listing lumen ratings based on optimized video output, while other manufacturers are still listing total (not video optimized) light output. So there could be two projectors rated at 1000 lumens and one is actually much brighter than the other. I think this may have been mentioned before by someone else, but it is something to note and ask when buying a projector.
 

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I will be doing some screen testing with Winter Mountain soon as well as some other grays.

From here on out the thread is open for questions and comments. Neutral grays certainly are not the only and definitive solution, but they do work extremely well. I actually conferred with some color scientists and college professors that teach color and light theory at some major universities, and I am taking college courses in color/light theory myself... so I would like to think what was presented is a well rounded and very valid option to at least take into consideration.

Without any further adieu, any questions? :)
 
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my experiences w/ GTI N8 and Glidden Gripper

wbassett mentioned GTI N8 and I guess I'm the only person who has tried this, so I thought I'd document this.

Files I've included:
Cin1* - Cinema 1 Dark mode on the Panny AX100
Cin2* - Cinema 2 Dark mode on the AX100
DVE* - calibrated w/ lights off using DVD Essentials (I thought it was too red and preferred the Cinema2 preset)
Glidden* - can't remember which projector mode this was, but the background was Glidden Gripper primer...washed out and unusable during the day...the GTI N8 is still usable w/ the AX100 in daylight dynamic mode

Glidden Gripper is also slightly reflective, so it showed *every* defect on my imperfect 200yr old horsehair plaster wall. GTI N8 is flat and hid everything. This is very important for those of you who are wondering why you don't use satin paint for a projector screen...don't unless your wall is perfectly flat...
 

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Discussion Starter #19
Nice shots and people say simple grays crush and muddy whites.

You said it was still unusable during the day, can you throw some shots with ambient light up and maybe a daytime shot when you have time?

What I found is lumens are essential for viewing with sunlight. Your projector is better and more powerful than mine, so I know you can get images as bright as I have shown. What I had to do though was use different gamma modes for daytime viewing and night time viewing. That's not all that bad though since my projector stores those settings. All I have to do is hit a button depending on when I am watching.

Silver Screen looks kind of close, but I was never able to get true whites with it. That has to do with the color shifting and when the screen shade goes darker it affects colors harder. Hence the reason for the research in neutrals. I'm not trying to bash SS, just let people know it does produce a color shift to some extent. Some projectors can compensate for most of it but there will still be some there. Some people (like me) just could not get past reds leaning towards purple. A D65 neutral or close to neutral gray will be the easiest screen to calibrate any projector to that is for certain. Also the 'V' curve will be the most accomodating for out of the box performance, but don't sell it short, a 'V' screen based on and rooted to D65 is a very good screen too.

As far as Silver Screen, even Behr acknowledges its blue lineage. Silver Screen is considered a neutral blue-gray hue. People can and will debate whether it is the ultimate find, but in the end it does go blue, even the company agrees with that.

Thankfully you didn't spend the $80 on a gallon of GTI (price plus shipping). I was really surprised at the CIE L*ab values that GTI sent me for the N8 paint. It wasn't as neutral as I thought it would be. It was close, but it didn't nail the D65 target dead center. Winter Mountain was within the D65 circle though.

Kenyee pointed a few things out elsewhere about this paint too that I didn't see him mention and I'll take the liberty of bringing them up and since he is the GTI expert now :) he can elaborate on them.

First this isn't a regular latex paint. It has an absolutely awful smell to it and shouldn't be painted without ventilation. It is also the flattest finish of anything out there and Kenya said it hides imperfections unbelievable well... probably why this is used by professionals in the photo and video industry. Amazingly, he only needed a pint to paint his screen, so it sounds like it covers extremely well, is that a fair statement Kenyee?
 
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Actually, Glidden Gripper was unusable during the day :)
GTI N8 is actually very usable during the day. I'll try to get some pics of it. It's enough for sports, but if you're watching a dark movie like the Matrix, I don't think it does that well either (but doubt any screen would in ambient light).
The Panny AX100 has 3 presets for dark and 3 presets for light conditions.

Yes, the GTI N8 covers well. It can actually be thinned a bit because I thought it was a bit too thick. A pint covered a 98" screen area w/ no problems. And I was dumb enough to do it in the winter (luckily it was a warmish winter in Boston so I could open the windows a crack)...the stuff reeeeeeked. The apartment stunk for over a day :p

Overall though, I'm still happy with it. I really wonder if Panasonic tested using it because Cinema2 matches with it so well...
 
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