|The two most popular screen aspect ratios used today are HDTV (16:9) and Cinemascope (21:9). Broadcast TV is displayed in the 16:9 aspect ratio as are cinemascope films by adding black bars top and bottom to fill out the shape of the HDTV format. This is also done with other formats such as 1.85:1 and 2.20:1, however these formats are quite rare and will not count for much of your movie collection. However it should be noted that 21:9 screens are gaining in popularity every week and are seen as the ‘bees knees’ projection format. This is because we can emulate what is done at the cinema by using an anamorphic lens to expand the image to fill the 21:9 screen. The other less popular format is the traditional 4:3 (1.33:1) format. This format is predominantly used in boardrooms for power point presentations etc.|
|SCREEN SIZES AND SEATING DISTANCES:|
|SCREEN GAIN and SURFACE FINISHES:|
Screen gain or ‘gain’ is a measurement of how bright a screen surface is. It has a reference standard by which gain it is measured, that being magnesium oxide (plaster). This is a zero gain diffuse material which measures 1.0, this means it has no gain at all. For Home Theatre applications, we have found a sweet zone for the gain of a material, being 1.1 to 1.3. Any higher than 1.3, the surface can glare or hot spot. See image simulation below to see what this means. Any lower than 1.1 means the image can appear quite dull and lifeless which can be likened to using a wall instead of a decent screen.
Reflective screens materials are the most commonly used in home theatre applications. This can also allow you to use a lower lamp setting on your projector. This of course can lengthen the life of your lamp and save you some dollars.
|Back in the day when projectors lacked lumens, high gain screens were all the rage. Today they are used less in home cinema because projectors are sufficiently bright enough. Some folks will still use them of course.|
|Reflective or diffuse screens materials are the most commonly used in today's applications.|
|The problem with textured materials in today's world of 1080P and beyond is seeing the texture during movies. The above photo shows the textured material and on the left side is a simulated image of what you can and will notice, particularly in camera panning moments or times where the image on screen is a light colour, such as sky or snow etc. The image 2nd from left is what you should be getting when using a good quality screen surface.|
The idea of the screen disappearing when being used is really what it's all about. You don't want to see the screen material, the frame or have any other distractions.
Our projection materials were designed with this in mind.
|VELVET & OVERSCANNING:|
Often overlooked and disregarded is the frame surround. The blacker the frame, the crisper and neater the image will appear. When using your projector, you will notice the edges of the image are quite undefined and soft, they seem to have some noise and grain, particularly on HDTV sources. Given the fact that you won’t want any gap between the image and the frame, the idea of pushing that soft edge onto the black velvet is a must. This also helps to isolate the image so it’s more enjoyable, immersive and cleaner. It helps the screen itself disappear when in use, which is
ultimately what you want to achieve.
Other screen manufacturers use what is called economy flocking, this is a much cheaper dark grey imitation velvet and does not compare to our Fidelio velvet. We only use black fidelio velvet on our frames and you truly need to see this to appreciate how black it really is. Call for a sample and we’ll happily post some to you. The black Fidelio velvet soaks up overscan with ease. It is the blackest material on the planet bar none. There is simply nothing this black anywhere. It is a true velvet with a 2mm pile. A truly luxurious material, made in the USA by JB Martin. Fidelio velvet is exclusive to Oz Theatre Screens and comes standard on all Majestic screens.
Black Fidelio velvet is on the right hand side. It is simply blacker than
anything else on the market. The other materials are flockings that some of our local competitors use.. they don't even come close to the black level of Fidelio, which is the blackest material known to mankind. $1,000 cash goes to anyone who can find and supply a blacker velvet than Fidelio black. Call for details.
These are the two most important factors in a projection screen besides colour temperature of the material.
1. The velvet should be jet black.
2. The material should be smooth.
3. The screen should vanish when being used.
4. The material must be non opaque, which means no light should be lost to the back of the material where possible.
Calibrating your projector is something that can yield stunning results. Movies are filmed at a colour temperature of D6500K (Kelvin). By calibrating your setup, you are attempting to get your image as close to the colour temperature of D6500K.
Professional Calibration is an art form of sorts and must be learned. The Imaging Science Foundation run certified courses on monitor calibration. Sure, you can go and buy a calibration unit like the Spyder3 below and learn it yourself. It will involve lots of trial and error and careful adjustments, re testing, pulling out your hair etc. It’s all about getting the colour settings correct when laid out on the shark fin colour gamut. Red, Green and Blue are the 3 primary colours and Cyan, Magenta and Yellow are the 3 secondary colours that sit between RGB.
Here is a link to the ISF for certified calibrators in Australia. http://www.imagingscience.com/dealers.php?search=Australia
|AMBIENT LIGHT, ROOM COLOURS AND PAINT:|
The darker your projection room the better the image will appear. Rosco’s black velvet paint is the matte black paint of all paints. See here for details on where to buy this. Black however is not the colour of choice for everyone. Many media rooms are dual purpose, lounge room, family rooms etc. Choose dark colours where possible and listen to your beautiful Wife! It’s her room too. Visit your local hardware store and ask for some advice. Try and avoid gloss paints
Some basic tips on getting the room dark:
>> Block out windows with either 3 pass blockout curtains or panels.
>> Treat the ceiling in a dark colour, even if only the front half. You would be surprised how much of a difference this can make.
>> Treat the screen wall in a dark colour - if you have limited choices as to how dark you can go and maybe want a feature wall, try and settle on a dark colour - maroon, navy, dark greys, browns etc.
>> If you’re screen is close to the side walls, consider making these a dark colour also.
>> Get matte paints where possible.
For those who want to order this paint, here are his details. It's $90 for a gallon, which is 3.78 litres.
It is called Supersaturated Roscopaint and the colour is Black Velvet #6003.
Adam P. Smith
Rosco Australia Pty Limited
42 Sawyer Lane, Artarmon NSW 2064
+61 (0) 2 9906-6262