Fixed Movie Projector Lens
A fixed movie projector lens will project an image from your projector onto a screen.
There are two main types of projector lenses. Lenses that can zoom and have a variable focal length mean you can place the projector where you wish and then focus the image to match the distance.
The other type is a fixed lens. Fixed projector lenses will only focus when they are placed at a specified distance from the screen that you are projecting onto. Rather than focusing the lens, you would move the projector backwards or forwards in order to project a properly focused image onto the screen.
Brands to look out for
A number of manufacturers make fixed projector lenses including Angenieux, Bell & Howell, Eumig, NOMO and S-ROSONAR. Different lenses fit different projectors so it is important to check that the lens you are considering purchasing is compatible with your projector.
Setting up a home cinema
Projectors are ideal for home cinemas, especially if you can spare the space to have a room dedicated to watching films or TV.
When choosing where to use your projector, you need to consider the distance between the screen and the projector; this is known as the 'throw'. As fixed distance lenses can only focus at one distance, a place with the right throw is especially important.
You also need to decide what kind of screen you're going to use. A blank wall is ideal, but a pull-down screen may be preferable if you're watching in the main room of your house.
Seating and how you move around the room is important too, as projected images are obscured if someone walks between the projector lens and the screen.
Another thing to consider is how to block out the light when you're watching projected images. Unlike with a TV , you'll need to completely darken the room when you're using your projector. A room with no windows is best, but one with small windows that can easily be darkened with blackout blinds would also be suitable.