People often use terms such as "ultra short throw" or "telephoto" to distinguish the type of projector. This term exists for a reason. Once you understand how the different types of projectors work and distinguish them, you can determine whether a telephoto, short throw or ultra-short throw model is right for your home.

What is a projector throw

The screen size of each projector is different, and the best projection screen size advertised by each brand of projector is also different. It needs to be set at a distance from the screen or wall according to the projection ratio of the projector. At a certain distance, the most suitable projection size can be obtained. This ideal projection distance, often referred to as "projection"

The projection ratio refers to the ratio of the projection distance to the width of the screen. It can also be understood as the ratio of the distance from the projector to the screen to the size of the projected screen. The calculation formula is the projection ratio = projection distance/screen width.

The smaller the projection ratio of the projector, the shorter the projection distance, the same projection distance, the greater the width of the projected image.

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The meaning of telephoto/short focus/ultra short focus

The throw ratio of ordinary projectors (telephoto projectors) is usually between 1.5-1.9. Most projectors use telephoto lenses, which means the projector needs to be farther away from the screen or wall. These projectors typically require a distance of at least seven to eight feet to project an 80-inch image, although longer distances can accommodate larger screens

When the throw ratio is less than 1, we usually call it a short-throw lens, which can project a larger image at a shorter distance than ordinary projectors. It is also an ideal choice for small-sized rooms or apartments.

When the throw ratio is below 0.4, we usually call it an ultra-short-throw lens. Ultra-short-throw projectors can minimize the distance between the projector and the screen and achieve the largest and largest picture

 Throw ratio of Dangbei Mars Pro 4K Throw Laser Projector

Factors to consider when choosing the type of projector that's right for you

Space

1. Due to the different projection ratios, different types of projectors can give full play to his role.
In smaller rooms, or for those who want to place the projector against a wall, ultra-short throw is the best option, and ultra-short throw projectors usually only need to project from a few feet away.

2.If the projector has a small space and there are children at home, the short-throw projector is the best choice. It is suitable for small rooms and can eliminate the interference of children's activities on the projection screen.

3.A telephoto projector is great for large, spacious rooms, and can be mounted near a wall, or placed on a coffee table, sofa, or stand to keep those cables nice and neat.Also, telephoto projectors are often the best option for outdoor viewing

 Cost

Most of the reason telephoto projectors are so common is that they are relatively cheap compared to other projectors, and they are also easier to install than short throw projectors, making them a great value for money

Moreover, the price of short-throw projection and ultra-short-throw projection will be much more expensive than ordinary projectors. Although short-throw projectors are not very expensive, the starting price is also around $2000. Although ultra-short-throw projectors have the highest price, they are the best in terms of brightness and effect, and they usually have built-in audio and built-in systems, which can also save space effectively. He is a true fan of home theater. is a good choice.

source:https://www.reviewgeek.com/113466/long-throw-vs-short-throw-which-projector-should-you-buy/