Thermally Stable Lens Mount ( this time around )

[Dale Launer]

Stainless is the only way to go

Why is that? When Invar and titanium expand/contract less than stainless steel?

[Jannard]

Everyone seems to have an opinion on this topic. Why not make them all and let the customer have their choice?

Jim

[Matt Uhry]

Everyone seems to have an opinion on this topic. Why not make them all and let the customer have their choice?

Jim

It's not the mount itself but the material between the sensor plane and the part you bolt the mount to... Bolting 12mm of Invar or Stainless PL ring to 40mm of aluminum camera body is not going to fix the problem. *

I'm totally in for a Stainless PL mount for the gains in strength, stability and stickiness.

Matt Uhry
www.mattuhry.com

* I don't know the Epic's internals, but it looks like the user changeable front mount plates bolts onto the external body. Using a sub-mount that connects to the sensor plane to the front attach points would be one way to solve this. Imagine a squarish table with a rectangular hole cut in the center. That part would be made of something that is reasonably thermally stable.

[chuck colburn]

The advantage a video camera has over a film camera so far as error in the viewing system goes is, that the film plane is the ground glass. Now I know that in itself has it's own inherent problems but at least one does not have to worry if the flange focale depth is the same as the ground glass depth and vicea versa. I believe if the sensor and lens mount be it interchangable or not are mounted in a common machined block of whatever metal you will maintain a flange focale depth at least as accuret as what the lens is capable of. I also think that the lens seat and locking ring on the camera should be stainless even if the rest of the lens mount/sensor mount assembly is aluminum.
Just my two cents...

Another couple of reasons for having an "optical block" type of assembly are that it allows one to align the bore of the lens mount to the center of the aperture and garuntees parallelism of the lens seat to the film plane.

[chuck colburn]

as i understand epic and scarlet (like red one) will not have a hardfront. so even if the plate (with the 4 screws) plus the PL mount is made of invar, the body (made from aluminum) will still expand.

image of a hardfront (invar) where the PL or nikon mount is seated - not connected to the front housing made of aluminum

Is that the new Aaton 35 camera?

[Jannard]

You know... it is an absolute miracle that anyone is getting good images out of a RED ONE. Really. If you look at it, it just doesn't make any sense. The whole body should technically be Invar, including the mount. Anything else just... well, sucks! If I do the math, the RED ONE, along with every other camera just can't make good images. The laws of science prohibit it.

I'm with you guys. Make an option where everything just can't move one iota. Then we would all be happy and be able to shoot feature films again instead of just fooling around with this other crap.

How many vote for an all Invar camera body and mount? Too heavy and much $$$? How about an all stainless steel body and mount? We are all in. Just tell us what you want and put up your deposit.

Jim

[Jannard]

We will make an optional Invar front body plate (integral with the sensor mount) and lens mount. We will also make an optional stainless steel front plate and lens mount option. Obviously they both will cost more money. But it now puts this thread to rest.

Oh, and you want a titanium set instead? No problem. We'll do that too. We aim to please. God loves a modular system.

Jim

[Fredrik Callinggard]

I here you Jim it's frustrating hearing all this voices, but no one is complaining about the image of RED One. Well, except for now and then :) , but mostly not.

See all this as us trying to be constructive not complaining. After all your learning and so are we. The mount as it is now is functional but it's definitely not perfect. The amount of times I've been standing swearing on set when backfocus been an issue are plenty.

At those times I've not immediately been able to say if it's the lens, the camera or the temperature.

So all we're trying to put in our suggestions in how to make it better. Letting us all sleep better at night, except for you guys who has to put in overtime back at the shop

I for example suggested stainless steel, because it's the cheapest that has proven itself to work. Although that is with film and it's more forgiving.

Depending on price I wouldn't be against for example invar.

No ones asking for the whole body to be in invar but BTW didn't you promise that Epic is an all titanium body :innocent:

and as a last word I want to say... that don't think we appreciate your hard work and your crazy idea about a camera for everybody. We just want to chime in so we can pretend we're a part of it.

[Jarred Land]

We will make an optional Invar front body plate (integral with the sensor mount) and lens mount. We will also make an optional stainless steel front plate and lens mount option. Obviously they both will cost more money. But it now puts this thread to rest.
Jim

and with that.. lets close this one down :)