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Q. How do I make a DIY Anamorphic Projection set up?

A. In reality, there are only three aspects to the DIY approach..The Lens..The lens Mount and the Screen..

LENSES:

You have two choices.
1. Buy a lens in kit form or partially assembled.
2. Buy the individual prisms, and make a box to hold them in position..

Lets start with the first option..

There are at least 2 individuals (no names given here) in the US and possibly more, and 1 in Australia, who will sell either a lens kit or a partially assembled lens..
They usually come with information on how to align the prisms and or the assembly of the unit..
The price you pay for this type of lens system, is far les than buying a commercial anamorphic lens..

The second option (and many have done this) is to buy your own prisms, make a box to hold them, and align the prisms yourself..

These prisms can be readily bought from Trophy Shops, sometimes online, or from individuals who will sell you a pair ready for mounting, but make sure that they are large enough..5"x7" being ideal..and that they don't have any engraving or other markings on them..

This is how easy it can be to set them up...

Several people have just placed their projector on a table or shelf, and just stand the prisms in front of the projector and angled them until they fill the 2.37:1 screen!..It's that easy..

Whilst they do get a Scope projected image, it's far from ideal, because the prisms will reflect light to the back and side walls..Also there is nothing to contain stray light fields, which will have a detrimental effect on the contrast of the projected image..

Like all lens systems, it's best to contain the optics in an enclosure that has a totally black, non reflective surface.

LENS MOUNTS:

There are numerous designs that have been made to hold the lens in place..
There are two types..FIXED and SLIDING..The latter may also be motorised with remote control..

Some have found (as I have) that they don't need a slide mount, and just rigidly mount the lens in front of the projector..
This means that all the aspect ratio's (with the exception of 1.33:1) are projected through the lens, and remain at virtually the same height for each..
On 1.78 and 1.85:1 images, you do lose a little definition, but barely noticeable, than if you had removed the lens and set the projector to the required format..But when you convert to an Anamorphic system, one tends to try and avoid these aspect ratio's as much as possible..
The other aspect of this is that if you watch all AR through the lens, you never have to reposition the lens..

If you do watch 1.33:1 movies, then a slide will be necessary to move the lens away..You may even have to re-position or use a higher screen with masking for the narrower AR's..which kind of defeats the purpose of CIH.. if your zoom control won't give you enough adjustment to reduce the height of the 1.33 image..

I actually have a slide mount, but I don't use it for the purpose it was intended..I have found it very useful for when I want to clean the lens..It's easier to clean it on a bench than up in the air, so I just slide it off the mount when cleaning is needed..

SCREENS:

Well I won't be going into all the various types of DIY screens that are out there...That's an individual choice..
Suffice to say that the screen aspect ratio should be 2.37- 2.40:1 for anamorphic projection..
The most common is 2.37, but some prefer to get the full width image when projecting 2.40:1 DVD's , but they generally are using some side masking for 2.35:1 movies..
Obviously, when you project 1.85 or 1.78 images, there are going to be black bars at the sides of the screen, but none top or bottom, so some prefer to have those bars masked anyway..

One very popular method of masking with CIH is the motorised, remote controlled curtain system, where you can stop the opening curtains at any point..
Others don't mind the black side bars, so they don't bother with any masking..

So, in a nutshell, this is all that's required to do your DIY side for Anamorphic Projection...
 

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Discussion Starter #2
Q. What equipment do I need for CIH Projection..

A. That will depend on whether you are planning to use SD DVD's or HD DVD's..

SD DVD..

For SD DVD you have two choices..to keep it simple..

Firstly, if you haven't bought any equipment yet, then the choice is very simple..You just buy a Projector that has inbuilt vertical stretch..That's all you need..You can buy any SD or upscaling DVD player you like..

If you are converting to CIH and already have equipment, then the choices are limited to a degree.
If your current projector already has vertical stretch, then the above applies..
If your projector doesn't have the vertical stretch facility, then you will need a DVD player that has that facility..
Some of the Upscaling HD players have adjustment for vertical stretch..

HD DVD..

HD DVD hasn't really caught up with CIH users as yet and choices of equipment are limited..
Again, the simplest way is to buy a projector that has vertical stretch built in..
There are several brands on the current market that can do this, so you're sure to find a suitable projector..
HD DVD players with vertical stretch on the other hand, don't exist at the moment, which makes it difficult if your projector doesn't have that facility..

The only other choice is to buy an external scaler..This will do the required stretch, but they can be expensive..
Some people have opted to buy a new projector, rather than spend more on an external scaler, which when they upgrade their projector, they will have no further use for the scaler..

So that's it..All the equipment you will need with the lens and the CIH screen, to get you started into the world of Cinemascope..
 
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