cooke breathing fix?

[Zakaree Sandberg]

I love my 25-250.. i get amazing looking images..
however as many know.. the cooke 25-250 suffers some heavy breathing.
Out of curiousity.. is there a fix for this? could i send this lens in and have someone perform some sort of open heart surgery to correct the breathing? or is it an issue that I will have to live with forever (with this lens)

 

[Larry McKee]

As soon as View Factor releases the Pro version of their follow focus system, your problems should be over. It is supposed to be programmable to perform a zoom as you focus to remove any breathing in a zoom lens.

 

[Pietro Impagliazzo]

As soon as View Factor releases the Pro version of their follow focus system, your problems should be over. It is supposed to be programmable to perform a zoom as you focus to remove any breathing in a zoom lens.

Interesting.

 

[Stephen Williams]

Hi,

Older designed longer Zooms do breathe quite badly, mechanically it's just on of those things. The shorter 20-100 & 18-100 hardyl breathe at all.

Stephen

 

[Matthew Duclos]

As soon as View Factor releases the Pro version of their follow focus system, your problems should be over. It is supposed to be programmable to perform a zoom as you focus to remove any breathing in a zoom lens.

Wouldn't that change your field of view as well as your depth of field...
There is no way to correct breathing in a cine lens. Well... you could... But that would be like correcting poor high speed handling in a hyundai. You would have to change a ton of internal components that would cost as much as just buying a Ferrari in the first place.
(Sorry to resort to the imprudent automobile reference, but it makes it easier to explain optics.) :nerd:

Moral of the story, buy an Angenieux Optimo and don't worry about it.:greedy:

 

[R. Schorman]

Could it be done in post if you place keyframes and adjust the scale from the beginning of the change of the focus to the end?

 

[Nick Gardner]

People have been making movies with lenses that breath for a hundred years. 99 percent of the time, you are changing focus because something is moving. Actor walking toward the frame, dolly moves, etc. It's not that huge of an issue.

Wide primes breath less than long ones due to the shallow depth of focus and the fact that you don't have to move the lens as far in or out to change focus.

I actually find it sort of weird when you rack and the frame doesn't move at all (S-4s, and canon HD glass), but thats just me ;-)

Nick

 

[Nils J. Nesse]

Breathing is nice.

 

[David Mullen ASC]

I find breathing to be annoying most of the time because it calls way too much attention to the shift in focus, especially if you are in the wide-angle end where you barely see the focus change but you do see a big change in focal length, which is confusing for the viewer. At least at the long end of the zoom, it is obvious that the breathing corresponds to a change in focus.

Most of the 25-to-250mm zooms breathe badly, including the 11:1 Primo zoom. You're better off with a short zoom, one with less of a zoom ratio like a 5:1.

 

[Mitch Gross]

Any form of correction to breathing, including a post solution or the View Factor counterzoom, will create other visual artifacts that are likely to be more annoying than the original breathing.

 

[Evin Grant]

Breathing is a fact of life unless you have the dough for an Optimo. I think the trade off is fine within the budgets I use my Cooke 25-250 MII on. If it's a big deal we rent an Optimo.

 

[Michael Lindsay]

Any form of correction to breathing, including a post solution or the View Factor counterzoom, will create other visual artifacts that are likely to be more annoying than the original breathing.

Interesting! I had obviously not thought this through enough.. I felt if the FOV was adjusted to compensate that would be enough? I suspected it would be far more tricky to do in post (perfectly) than some suspect but with 2 motors, a zoom and somebody clever?

It is also interesting that personal standards change with technology. I used to think UP didn't really breath much. Post MP they seem a little wheezy...

regards

Michael

 

[Dominic Cochran]

Any form of correction to breathing, including a post solution or the View Factor counterzoom, will create other visual artifacts that are likely to be more annoying than the original breathing.

Any is a big word here Mitch, but you seem pretty certain. If the compensation on the VFS unit is matched to the specific lens, what are the artifacts you speak of? All I can think of is FOV, but if the speed ramps correctly it should be fine right?

 

[Stephen Williams]

but if the speed ramps correctly it should be fine right?

Hi,

Words like "if" & "just" they just roll of the tongue so easily.

Stephen

 

[Tony Covell]

The cooke lenses are not prone to breathing unless they are very old and worn. Find a good cooke workshop starting with Paul Duclos in LA and spend some cash getting it corrected. It will then last untill its next yearly service.
Good shooting
TC.

 

[Stephen Williams]

The cooke lenses are not prone to breathing unless they are very old and worn. Find a good cooke workshop starting with Paul Duclos in LA and spend some cash getting it corrected. It will then last untill its next yearly service.
Good shooting
TC.

Tony,

I think you will find the 25-250 MK1 does breathe quite badly. Paul's son Matthew Duclos has posted in this thread.

Stephen

 

[Matthew Duclos]

We currently have a Cooke 10x MkI and MkII in our shop. I might do a comparison test to show the difference. Not that it will matter, you cannot correct the issue. "fixing in post" is not fixing. It's just a compromise.

 

[Mitch Gross]

There are a pile of little optical events occuring during a focus pull on one of these lenses, far beyond "just" a change in FOV. As one would attempt to correct for this with a slight matching zoom, these issues would become quickly apparent. There are many parameters with which to judge a lens, including color shift, contrast, chromatic abberation, tracking and so on. It might not be an obvious thing, but as much as the image retains field of view it will still appear to have "something strange" happening in the image.

This is actually easy to see. Have someone pull focus on a lens while you compensate with the zoom. Do it a few times and you'll be able to match the speed fairly consistently. Then you'll be able to see these other odd effects.

If it was that easy to fix don't you think the lens manufacturers would have built in amachanically linked compensator from the start? A classic example of this is the 16mm Zeiss 10-100 T2. Zeiss basically decided screw the breathing in order to get the sharpest, cleanest image possible. If they addressed the breathing with the technology at the time it would have been to the detriment of other factors.

 

[Dominic Cochran]

Hi,

Words like "if" & "just" they just roll of the tongue so easily.

Stephen

Hi,

I agree, it's a bit similar to contrary responses with no content(indeed, like this one).

Dominic

 

[Dominic Cochran]

There are a pile of little optical events occuring during a focus pull on one of these lenses, far beyond "just" a change in FOV. As one would attempt to correct for this with a slight matching zoom, these issues would become quickly apparent. There are many parameters with which to judge a lens, including color shift, contrast, chromatic abberation, tracking and so on. It might not be an obvious thing, but as much as the image retains field of view it will still appear to have "something strange" happening in the image.

This is actually easy to see. Have someone pull focus on a lens while you compensate with the zoom. Do it a few times and you'll be able to match the speed fairly consistently. Then you'll be able to see these other odd effects.

If it was that easy to fix don't you think the lens manufacturers would have built in amachanically linked compensator from the start? A classic example of this is the 16mm Zeiss 10-100 T2. Zeiss basically decided screw the breathing in order to get the sharpest, cleanest image possible. If they addressed the breathing with the technology at the time it would have been to the detriment of other factors.

Thanks for the response Mitch, and I remember that 10:1 Zeiss you mentioned(and it's trade-offs) very well. My main concern with the VF rig is just that the speed itself won't correspond correctly, rendering any possible optical artifacts a non-issue since I wouldn't be using that function anyway. It will be interesting to see how it turns out either way.