2/3rd Inch relay for Brevis available

philip bloom

philip bloom

Veteran
From a company in Greece

http://www.motionfx.gr/ggrelay.htm

Looks very interesting but suffers the same problem that the old relays for the Letus HD and Letus XL had 2.5x magnification...I expect the one Dennis himself is making won't have that problem!

They will make versions for all the other adaptors later.
 
Looks like it'll work for Letus as well. However magnification is pretty large number as stated.

Must wait for Letus Relay. :D I smell success.
 
I understand how this works, but I'm a little confused when you guys say 2.5x mag is a concern? Does this mean it's loss of resolution? But in any case, the stills and video looked great.
 
They seem like a really nice bunch of guys. They have finished the product, but the product run is very small. They have said they will try and let me try one out for a few days.

The 2.5x is such a shame though, I love my wides so much and as England is so small we don't have much space. It's ok for you guys in the states, you can just step back a bit. If I did that I would be in the English Channel and end up getting wet. I don't like getting wet, especially with a camera.
 
P Jamal sent me the original link. I know Letus are working on a 2/3rd inch. Not sure what cinevate plans to do, i know they have 1/3rd inch in the works but are they planning on taking on the pro 35. Be cool if they did!
 
Evangelos the maker emailed me this...

"The relay takes an image size of 24mm X 13.5mm (Super 35) and project it to a size of 9.59mm X 5.35mm (2/3 3ccd HD 16:9). So 24mm divided by 9.59mm equals 2.5 magnification factor. I can build a version for standard 35 or for photographic image size but it’s a different construction in CNC."
 
Hello to all forum members

A relay lens it just takes an image from the ground glass and projects it to the sensor. The ground glass adaptor is doing the depth of field conversion, so there is no loss of field of view unless the ground glass adaptor is a bad design. With Brevis35 the image is exceptional with no loss in DoF or field of view.

A super 35 lens of 50mm with the use of that system it retains all his characteristics and behaves as a normal 50mm…

The relay lens has to be as transparent as possible with no light loss, apo chromatic and with the highest MTF, in order, the system (GG adaptor and relay lens) to maintain the character of the lens that’s being used.

I’m open to any questions regarding the GG.relay lens.

Best regards to everyone!
 
There must be a misunderstanding…

In order to make the magnification 1:1 you either need a sensor of 35mm or a lens of 2/3…

It’s understood that the ground glass adapters are doing the job for the DoF and FoV conversion and there no physical way to project a bigger image to a small sensor without a magnification.

None even Dennis or Letus could not create a relay with no magnification. Is like you asking to go to the moon by walking…

The request it’s simply not logical.

The early days, relays like the Angenieux/Zeiss CLA 35 HD didn’t have a ground glass, so yes these relays they change everything like Barry Green states. In order to work our relay NEEDS a Brevis35 or a Letus or some kind of ground glass adapter.

We just solved the problem of mounting these adaptors to 2/3 cameras…

So there is no drawback and this is evidenced in the sample footage, that I also state, the distances from the objects so an experienced DoP could understand if there is a loss in either DoF or FoV.
 
Evangelos, is the relay not just zooming into the ground glass, doing the job of what the stock lens of the camera would have done when screwing the brevis onto the front? Obviously when you do that there is no magnification. Excuse my ignorance as I have never used a relay based adaptor.
 
Yes Philip the relay replaces the camera lens and it’s zooming to the screen in a fixed manner for a 24mm x 13.5mm size (for the GG.relay/24) or 36mm x 24mm (for the GG.relay/36) with the maximum quality possible…
 
so why then is there magnification if there is none when using a stock lens? If the zooms in the same amount as you would normally then surely the image would be identical therefore no magnification?

The way Evangelos describes it he is going from 35mm lens to Brevis to relay to 2/3rd inch chip. Whereas I have always gone the other way, with the camera operator deciding the field of view by deciding how much to zoom into the gg. With the Letus, I can make a 20mm and 60mm if I want to purely by zooming in more, but I tend to choose what the lens actually is supposed to be. So why can't this relay just not zoom in so much?
 
philip bloom said:
so why then is there magnification if there is none when using a stock lens? If the zooms in the same amount as you would normally then surely the image would be identical therefore no magnification?

The way Evangelos describes it he is going from 35mm lens to Brevis to relay to 2/3rd inch chip. Whereas I have always gone the other way, with the camera operator deciding the field of view by deciding how much to zoom into the gg. With the Letus, I can make a 20mm and 60mm if I want to purely by zooming in more, but I tend to choose what the lens actually is supposed to be. So why can't this relay just not zoom in so much?
Click to expand...

That’s why the size that I use is the 24mm X 13.5mm (super 35) which IS the image size that all the 35mm movie lens are designed. In that way we retain all original characteristics of these lenses. Of course in order to use Canon or Nikon photographic lenses its needed different magnification factor so a GG.rellay/36 with 36mm X 24mm should be used in that case instead of GG.relay/24 (super 35) that is for PL mount lenses.

In the sense that you describing what you understand, there is no magnification, but from an engineering point of view in the physics of optics this is a magnification of 2.5x…
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