Homemade projector screen - Principle & how to DIY

Written by Jacklyn Chen

Projector screens are generally divided into two types base on their functionalities: reflection projector screen and transmission projector screen. It can be also divided into soft and hard screen base onrepparttar materials they are made from.

Home theater generally uses soft reflection screen. My brother-in-law originally wanted to buy a 1000 (~$150) so-called "import screen", but a friend of his who sells projector screens told him that it is hard nowadays (in China) to distinguishrepparttar 149052 genuineness of an import screen, it is hard even for himself. Some of them that are labeled with 'import' or 'joint capital' were actually manufactured somewhere inrepparttar 149053 south of China. He felt that he'd rather to buy a 300 domestically manufactured screen with good feelings than buy this kind of "import screen". What this friend said makes perfect sense. But after doing some research, my brother-in-law found that all screens onrepparttar 149054 local market are made from high gain Bolivian bead that is used for projecting newspaper clips, they are simply not suitable for video frequency.

Theoretically speaking, a white wall with one smooth side actually isrepparttar 149055 best "screen". Because its gain is 1, meaning thatrepparttar 149056 light projected can be completely reflected out, which is an ideal state of being "no absorption, no gain". Unfortunately, forrepparttar 149057 purpose of absorbing and proliferatingrepparttar 149058 sound wave, he already maderepparttar 149059 wall a background wall with sound-absorbing material and plywood installed. making it impossible to serve as a "projector screen', he had to find another solution.

You might be wondering at this point: why do people still bother purchasing expensive screens if we can all use white walls?

Well, there are always benefits and advantages of using a professional screen: convenient, artistically beautiful and dignified, good screen can also make uprepparttar 149060 insufficiency of a projector and improve visual effect. Amongrepparttar 149061 expensive screens, one type is "gray screen" (cost about 15,000, roughly $2000). This kind of screen probably was originally designed for liquid crystal projectors. The biggest problem with liquid crystal projector is thatrepparttar 149062 color appears dark and grey, insufficiently calm. This is its "congenital defect" that is caused by its liquid crystal board and path of rays.

Regarding gray screen, we all know that gray is merely a lighter black, and black absorbs all visible light. Gray can only partially absorb visible light, it is like brightness ofrepparttar 149063 picture is reduced. If you have used any picture processing software's "brightness / contrast gradient" option, you should certainly have noticed such phenomenon that reducing brightness is equivalent to increasing contrast gradient? Same concept, sincerepparttar 149064 brightness has been reduced, it in turn increased its contrast gradient. The black effect gets improved due torepparttar 149065 bigger contrast. We can also experiencerepparttar 149066 same effect when we look out throughrepparttar 149067 sunshade glass of our car. In fact, there are many ways to just reducerepparttar 149068 brightness, you don't have to use gray screen. There are magazines recommending puttingrepparttar 149069 light gray filter of a photographic camera torepparttar 149070 projection lens,repparttar 149071 principle isrepparttar 149072 same. You can even use more simpler method, namely you need to adjustrepparttar 149073 projector's output brightness or increaserepparttar 149074 contrast gradient. No need to spend a cent, you may achieverepparttar 149075 similar effect, butrepparttar 149076 premise is that showroom must be dark enough.

Try some new music!

Written by Emily Sigers

Stuck in a music rut?

It happens. After listening to your favorite song 1,379,614 times, you will, eventually, get sick of it.

So you find a new favorite song, all too aware that you'll soon grow as tired of it as your previous pick.

This is even more likely to happen when you only listen to one type of music, a habit I've never subscribed to and have a very hard time wrapping my mind around (my mind's not big enough to stretch that far). With all ofrepparttar wonderful types of music available, why limit yourself to one or two genres?

Do yourself a favor and start branching out.

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