In theory - Anamorphic extender?

[Christoffer Glans]

Is it possible to create an anamorphic extender for EF lenses? I mean a mount extender that squeeze the image and is placed between the lens and the camera.
Most EF lenses cover full frame 35mm stills, which is larger than on the Epic. So with the anamorphic extender we could get anamorphics with usual spherical lenses.

This is because of the look and feel of anamorphics, sometimes you want that even though you loose resolution.

 

[Martin Schneider]

You wouldn't get the "anamorphic feel" just the 2x (or whatever ratio) squeeze because the anamorphic element sits at the rear not in the front or middle. So no horizontal flares (because that happens in the anamorphic front element) or oval bokeh (because the iris is in front of the anamorphic element and gets squeezed along with the rest of the image).

Most anamorphic zooms are rearconverted btw. even the new Angenieux 2x. The newer Panavision and Hawk Zooms are purpose designed front-anamorphic.

 

[Christoffer Glans]

What about this?

http://www.reduser.net/forum/showthread.php?108766-Letus-AnamorphX-Adapter


I don't think it gives you enough of the anamorphic feel that you want, but it seems to work. Why wouldn't there be horizontal flares if it was positioned in the rear end of the lens? If the image is squeezed on the sensor the flare will become horizontal when unsqueezed.
But the main part is that I want the bokeh and most important, being able to increase the width of the image for certain lenses.

 

[Martin Schneider]

The Letus would work just fine for getting the anamorphic Look (Flares and bokeh), albeit with a 1.33 Squeeze. The only downside is, not being able to rack Focus between close and infinite - you have to select near-mid-far on the Adapter as well (which is probably fine for most shots).

AFAIK The horizontal flare has nothing to do with the squeeze-desqueeze per se, it is a horizontal line in the squeezed image to begin with. It happens because of the curvature of the anamorphic element, which is not "round" like normal lenses but straight in the vertical and curved in the horizontal - light needs to hit there for the horizontal flare to appear. Good luck getting stray light right down to the lens mount . BTW because of this curvature the anamorphic has to be perfectly alligned, otherwise your squeeze is slightly diagonal.

I could be off concerning the bokeh but :
In a front (or middle) anamorphic lens only whats in focus has perfect 2:1 (or whatever) squeeze and the out of focus areas have slightly more squeeze and are oval (even in the squeezed image - it has more squeeze than whats in focus) this image gets projected onto the sensor/filmplane. That only happens when the anamorphic element is part of the optical path of the light until it leaves the backelement.

But when using an extender like you describe, you project a "finished" spherical image (with round highlights) onto the first element of the extender (where the backfocus of the lens projects correctly) then this whole image gets squeezed by the anamorphic element and another element backfocuses onto the sensor/filmplane. So you don't change anything about how that image is created within the lens, you just grab it and squeeze it, kinda like squeezing the image digitally in Post. BTW you would easily loose 2 stops or more with an extender like that...

Rearadapted Panavision Zooms might do something funky to avoid that, but these are not extenders you can take off.

It all comes down to the wacky design and inherent flaws of incorporating the anamorphic element into the lens design

Anamorphics are fun...