turn a regular video projector in short-throw model for ~40$

As a video artist, I like to do video projection directly from the stage.
I appreciate this approach because it\'s easier and faster to install than hanging a video projector on a grill --
More complicated than other installations.
The technology does a good job, especially in the case of retro, the effect is good
But efficiency is often limited by the depth of the stage.
In order to solve this problem, the simplest solution is to use shortthrow video-
Projector, but it can be expensive, especially when you are looking for highlightspower (e. g.
3000 lumens almost $5000).
So I \'ve been looking for a cheaper solution to put my 6000lumens-video-
The projector is short in power-
Throw Projector
I did a lot of research and testing with the mirror;
It\'s fun to use, but not practical, and it\'s too fragile to adjust to transport.
Finally, one day, when I took pictures, I just thought about how the light went through the wide angle object. That\'s it !
I\'m looking at the same principle. . . . .
But from another perspective
This is for the story.
The solution is easier: just find a way to fix and adjust a wide angle lens in the same way as the light field of my video projector.
To do this, you need to: because there are so many types of videos --
Projector, it is not possible to propose general support that matches all projectors.
In my case, I showed you the technology I used to repair aluminum tubes and I\'m sure your creativity and ability will help you find the same way (or a better)result.
I use wooden boards to support under the projector.
I use it to hang the projector and use this support to fix it on the counter
The pipe of the aluminum pipe will be received.
I think it should be easy to create an equivalent with wood or hardware components.
It is important to be careful: the pipe must be online and align as much as possible with the projector\'s target.
To achieve a fully adjustable installation, I used three different parts.
As you may see, these sections look quite large.
At first I put too much torque on the screws and the clamping part broke;
So I added the size.
It also explains the fact that in order to use it, the system must be strong enough to resist rapid operation and rigid enough (
No action)
Long installation is allowed (
In my case, up to 8 hours).
Base bracket: make contact between aluminum pipe and bracket.
It allows the lens to move away and adjust the vertical position of the projector lens.
Gasket: allows to adjust the height of the lens on the vertical axis lens holder: clamp the lens and allow to adjust the tilt of the lens. All screws and bolts are made of m m6.
In order to have a more compact system, please feel free to modify it.
I chose a plastic handle for quick adjustment (
But not needed).
As you can see on the picture, commercial screws may not have the right length to fit the system perfectly (
Or like me, you don\'t want to buy a new one.
So, you can adjust with some washers, see the screws, adjust the size of the bracket to fit. . .
If you want to use multiple lenses, you can pre-
Install the lens on the holder to get a faster switch.
The model of the lens holder can be easily identified using different plastic colors.
After installing the system, place the lens in the center of the projector\'s light using different adjustments.
Displays images of the entire surface of the lighting using a projector (
Like Test mode)
, Take a look from the side, adjust the lens to display all the rectangular images (
When there is a little dust on the lens, it is easier ^).
Don\'t try to fit the rectangle exactly on the frame of the lens, it\'s better to have a small gap to use the center of the lens more (see picture).
From Optics (Or professional)
This system cannot replace a real short.
Video projector;
But it has saved my \"life \". . . :)Result: (with a 0. 43x lens)
Especially when considering the price and working hours, the result is acceptable (~10 hours).
This lens system can obtain an additional surface of almost 125%. Without lens (
Left projector)
51x38 is displayed.
5 cm image and system, it jumps to 76. 5x58 cm.
It adds size 1.
5x, the entire displayed image is in 2. 2x.
Experience feedback after a few years: the weakness of this system is the distortion and color difference generated by the lens (see pictures).
The wider the lens angle (or ratio)
The bigger these problems will be.
X0 is a good compromise for me. 5 (I use the x0.
47 lens 90% time).
In my opinion, the color difference is usually negligible, because the color difference is particularly obvious when projecting pure white.
You can fix the distortion in different ways: with mapping software, you can fix the distortion by modifying the projected surface, modifying the image, or the video source. . .
It should also be interesting to try different lens quality or suppliers.
In any case, it seems to me that this solution is reliable with unbeatable quality/price ratio and opens up interesting possibilities in terms of video projection (
Through prisme, light transposition, specific lens effects ,. . . )
Thank you for your attention.
I look forward to reading your feedback! ! !