16:9 Screen Vs. 2.37:1 CIH Screen

[Prof.]

These drawings show how the two different systems work, when it comes to screen size, image size, and aspect ratio..

The first one is for 2.35:1 DVD's..

[Prof.]

This is for 1.85:1 DVD's..


When a 1.85:1 image is vertically stretched, you do lose a bit of the image top and bottom..
Some people prefer to use what's called the "Pass through mode"..That just means that the light path is no longer through the anamorphic lens..
So the corect AR is maintained..

[Prof.]

And this is 1.78:1 DVD's..



As you can see for this AR, the Scope screen will have black bars at the sides..These bars can be simply masked, or as some people do, just leave them as they are..

[Prof.]

Reserved 3

[Prof.]

Here are some screenshots showing the various stages of converting your standard 2.35:1 DVD image to a full cinemascope image.
The camera hasn't picked up the blank part of the screen in the first two sequences, but you can see how the image changes..

All the pics were taken from the same position with the camera mounted on a tripod, and all at the same zoom setting..

The first shot in each sequence shows the normal image without any zoom on the projector..and without the anamorphic lens in place.


Now the images are vertically stretched by the projector or DVD player to the full height of the screen.

.
And finally the lens is in place, optically stretching the image to the full width of the screen, and restoring the correct geometry.

[Mark Techer]

Well done Prof, they are very CIH demo shots.

The best description I ever got was from the RUNCO guys at CEDIA. They did their speil as if no-one else had it, and they made simple.
They said CIH is two parts - Sclaing + Optics.

I guess the most difficult part is understanding the scaling aspect of the process. This is the electrical manipulation of the signal to -
A. rid the black bars and
B. use the full panel for max rez and image brightness.

Optics are a science all by themselves, and the part that makes understanding the difference between an anamorphic lens and conventional zoom lens is that the anamorphic lens only magnifies in one direction - typically horizontally.

The exact amount of magnification must equal the amount of electical scaling applied to the image.

The amount applied to video is based on 1.33x because 1.33 x 1.33 = 1.78, so 1.78 x 1.33 = (when rounded) 2.37. It simply takes the next step as well as provides an extension for 1.33:1 displays - IE you can obtain 1.78:1 optically by using a 1.33x stretch lens with a 1.33:1 projector...

Mark

[Prof.]

Thanks Mark..

I hadn't been having much success at setting the correct white balance on the camera, until I came across your method of setting it...Worked a treat..

[Richard W. Haines]

While in theory this makes sense, the cost is so expensive for the lenses is it worth it?
I'll put it this way. When I zoom up and eliminate the slight black borders on my 10
foot wide screen while watching the HD DVD of "The Wild Bunch", it looks almost as a
35mm print shown on the same size with anamorphic lenses and at the same distance
of 15 feet from booth to screen. What size screen are you using for comparison and
is worth the cost of the lens to remove the black borders and use more of the pixel field.

One of the disadvantages of using any anamorphic lens is that you lose some resolution when you compress and expand the image which is why 70mm widescreen looks so much better than a 35mm
anamorphic print even when the 70mm print was optically enlarged from a 35mm negative.

[Mark Techer]

Hi Richard,

What projector are you using? Think of it this way - regardless of the rez, you will able to use the full rez of the projector all the time. If you take trueHD, you start with 1080 vertical pixels for 16:9 and progressively loose vertical pixels as the image gets wider. By the time you reach 2.35:1, you're down to about 810 vertical pixles.

One method is to zoom in the image. This is very much projector and placement dependent - some projectors just don't have enough zoom from a given throw. If your projector does have the range, what you end up with is enlargening of the pixels in both the horizontal and vertical directions. Seating distance pending, you may even see pixel structure.

The other method to to use an anamorphic lens. Yes some models are expensive, but there are also cost the effective approach that can work as well - see HERE. When you employ a 33% stretch lens, you are able to horizontally expand the image by 33%, but not affect the vertical rez. Researh has proven that we are more sensitive to vertcial rez than horizontal, so using an anamorphic lens keeps the pixels at the same height. And instead of throwing away about 270 pixels, you image is now made of the FULL 1080 vertical pixels. It is denser and more film like. I have seen systems that DO look as good (if not better) as 35mm film on a small screen (I define a small screen as anything less than 4.0m). It is like watching a brand new release print...

Mark

[Prof.]

Richard W. Haines wrote:

While in theory this makes sense, the cost is so expensive for the lenses is it worth it?.

Unfortunately this is how many people view anamorphic lenses, and something way beyond their reach.. As a consequence, they don't even consider it as a possibility and don't look any futher into it..

Commercial lenses are very expensive, sometimes thousands more than some projectors..

I was of this belief about a year ago, and for me an anamorphic lens was just a dream..Something that I would never be able to afford, unless I won Lotto..

Then I came across Mark's Aussiemorphic lens, and for the first time it looked liked it would be possible to have an anamorphic lens..
I read everything I could find about it, and other peoples views on the lens who had purchased one..
and looked at a number of screenshots with the lens fitted..

I finally decided to buy one, still a bit hesitant as to whether I was going to get a quality lens or not, particularly when compared to lenses costing thousands of dollars..

Well to say that I was thrilled with the results would be an understatement..
I won't say what it cost me, except it was a fraction of the price of a commercial lens..

My point is this...You don't have to pay an arm and a leg to have an anamorphic lens..There are other ways of obtaining a lens that will perform almost as good as very expensive ones..
You can just buy the prisms, and put the lens together yourself..Or you can buy a lens kit (like mark's) and set it up yourself...

Believe me...If I can afford it...anyone can..

[Mark Techer]

Thanks Prof and why I posted that link...

Mark

[tonyvdb]

Prof. wrote:

Then I came across Mark's Aussiemorphic lens, and for the first time it looked liked it would be possible to have an anamorphic lens..


Believe me...If I can afford it...anyone can..

Hi Prof, Im interested in looking into doing this sometime down the road but have a few questions. Where do you get this lens you speak of, I went to the link but dont see a price or place to buy it.
Also will it work on any projector? I just have a Sanyo Z2.

When you say affordable what do you mean by this as thats a relative word when dealing with little to no budget.

[Prof.]

tonyvdb wrote:

Hi Prof, Im interested in looking into doing this sometime down the road but have a few questions. Where do you get this lens you speak of, I went to the link but dont see a price or place to buy it.

Tony, I bought my lens from Mark Techer, who is the maker of the Aussiemorphic lens..this link should give you all the info. you need
http://cavx.blogspot.com/2007/04/4-prism-lens.html

Also will it work on any projector? I just have a Sanyo Z2.

Shouldn't be a problem..Mark's lens works on just about all projectors..

When you say affordable what do you mean by this as thats a relative word when dealing with little to no budget.

Well I bought the Mk.1 lens and it cost less than $400AUD...the Mk.11 is a little dearer, but it now comes with coated optics and a slide mount..

BUT...you can even do it for a lot less if you're prepared to make up your own lens, by just buying a couple of prisms and assembling them into a case..

I would suggest sending a pm to Mark and ask him about how to get hold of some prisms...
You might like to click on this link as well...http://cavx.blogspot.com/2008/01/b-s...-for-sale.html..

When you are ready to set up for CIH projection and assembling the lens, Mark will give you all the help you need to correctly set up the lens...

[Mike P.]

Prof, I'm not familiar with the Sanyo Z2, but if it doesn't do the vertical stretch to the image, then a scaler would also be needed, correct?

[Prof.]

Mike, the Z2 probably doesn't have vertical stretch, in which case he will need an external scaler if he's playing HD DVD's..
If it's ony SD DVD's, then just an upscaling player with a VS facility is all that's needed..

[Mark Techer]

I'm sure that the Z2 does work for SD, but may not work for HD. I have started a thread on using a HTPC with a program called YXY, which is how I got around the VS issues for HD on my system...

Mark

[John Simpson]

I just wanted to add my recommendation for Mark's product. By all reports it's fabulous for the price, and I think he needs to be congratulated for providing us with a cheaper option to those other ridiculous prices.

Aussie Aussie Aussie!

[Mark Techer]

Thankyou John. I only hope that I can continue in the future with the upcoming developments to Aussiemorphic Lens including the MKIII by keeping the pricing real...

Mark

[Prof.]

Mark..How is the progress going on the Mk.111..Do we have a release date yet?
Also can you tell us what the difference will be over the MK.11.?

[Prof.]

John..How is your CIH setup going?
I think the last I heard, you were about to get the screen set up..Any further progress?

[Mark Techer]

Prof. wrote:

Mark..How is the progress going on the Mk.111..Do we have a release date yet?
Also can you tell us what the difference will be over the MK.11.?

Unfortunately, no set date. The MKIII will be released in stages –
1. Injection Molded Plastic case that allows both future upgrades as well as backwards compatibility.

2. Focal correction or “astigmatism correction” element

3. CA correction where the new prisms will be made from two different types of glass that have been bonded together.

All of this takes time and money, and so a slow process when developing and funding a project like this yourself...

Mark

[Prof.]

Mark Techer wrote: