Super 16mm zooms that don't breath

[Albion Hockney]

Was curious on experience with various lenses on super 16mm. I was planing on using a Zeiss 11-110 Zoom on a shoot with a long slow zoom shot. but apparently I have heard the lens breathes during zooms and won't hold focus? Are there any zooms that won't be a problem.

 

(When I say breathes I don't mean the subtle zoom effect created by pulling focus but instead the loss of focus while zooming...the opposite effect I suppose)

[Alex Nelson]

Cine zooms don't usually change focus during zooming unless the back-focus is off. If a lens is properly collimated to the camera, by shimming the mount on either the lens or on the camera, it should hold focus through the full zoom range.

[Satsuki Murashige]

Lens breathing refer to the image expanding of contracting when changing focus. When a lens holds focus throughout the zoom range it is referred to as 'parfocal.'

 

Practically all s16 zooms were designed to be parfocal, so like Alex says as long as the lens and the camera lens mount are properly collimated then the focus should hold while zooming. The Zeiss 11-110 is parfocal when correctly collimated. The close focus is 5' and the lens does breathe quite heavily. Canon has several s16 zooms like the 7-63, 8-64, 11.5-138, and 11-165 that are not quite as sharp but focus much closer and breathe less. Might be better for what you are trying to do.

[Albion Hockney]

ok hmm got some misinformation. thanks for clearing it up. since the focus is holding one place during the take I dont think the breathing will be an issue.

[Kenny N Suleimanagich]

I can confirm that the 11-110 is parfocal. Though it does breathe.

[Gregory Irwin]

I don't know of any zoom lenses that don't breath. Perhaps the new Fujinons don't but I'd have to check on that. Anyone know about those?

 

G

[David Mullen ASC]

Some breathe less than others, just compare the 4:1 Primo zoom to the 11:1, for example.

 

When I shot 16mm decades ago, I recall the Canon 16mm zooms breathing less than the Zeiss and Angeniuex 16mm zooms.

[Brian Drysdale]

The Cooke 16mm zooms don't breath that much.

[Gregg MacPherson]

The Cooke 10.4-52 was famous for not breathing. Quite an old lens now, but still a really good one. Looking at the frameline during a pull, magnification does clearly change, but maybe it's not very impactful on our seeing compared to the focus shift. And maybe it was just much better than the Zeiss with that.

[Gregory Irwin]

The Cooke 10.4-52 was famous for not breathing. Quite an old lens now, but still a really good one. Looking at the frameline during a pull, magnification does clearly change...

Seeing the magnification shift during a focus pull constitutes the very definition of breathing. Even in David's example of the Primo 4:1 and 11:1, there is still some degree of a magnification shift. I still don't know of any zoom lens that doesn't breathe. Just too many elements and lens groups moving not to prevent breathing.

 

G

[Gregg MacPherson]

Seeing the magnification shift during a focus pull constitutes the very definition of breathing. ....

 

This seeming contadiction between what is said and what it really is, is already expressed in my post. If some prefer one lens over another it would be due to one breathing less than the other. If the breathing is unobservable in a film because our "seeing" is busy with something else, so what.

[Gregory Irwin]

This seeming contadiction between what is said and what it really is, is already expressed in my post. If some prefer one lens over another it would be due to one breathing less than the other. If the breathing is unobservable in a film because our "seeing" is busy with something else, so what.

 

Ok. I see what your saying. Your point is that the breathing doesn't have an impact if it's disguised by the focus pull - whether it's really there or not. Correct? I have to look at it in a more absolute way since magnification shifts affect VFX so much. That's why we have to do visual effects lens grids all of the time now as a part of our usual routine. Even though the new Master Prime Anamorphic lenses are not zooms, we were extremely impressed with the zero breathing they display. That's not usual for any anamorphic lens. Pretty good.

 

G

[Gregg MacPherson]

Hey Greg,

Yes that is what I thought.

I hadn't thought of the VFX thing. Now I get why you are more stringent about it.

 

Cheers,

Gregg (2 Gs)

[Gregory Irwin]

Hey Greg,

Yes that is what I thought.

I hadn't thought of the VFX thing. Now I get why you are more stringent about it.

 

Cheers,

Gregg (2 Gs)

Thanks Gregg!

 

G (2 Gs too but at either end!)

[Aapo Lettinen]

I think the cabrio 19-90 does not breath much at least at the mid range. internal focus lenses breathe less by my experience so may be something to do with that

Edited November 7, 2015 by aapo lettinen

[Kalle Folke]

The Cooke 10.4-52 was famous for not breathing. Quite an old lens now, but still a really good one. Looking at the frameline during a pull, magnification does clearly change, but maybe it's not very impactful on our seeing compared to the focus shift. And maybe it was just much better than the Zeiss with that.

 

Seeing the magnification shift during a focus pull constitutes the very definition of breathing. Even in David's example of the Primo 4:1 and 11:1, there is still some degree of a magnification shift. I still don't know of any zoom lens that doesn't breathe. Just too many elements and lens groups moving not to prevent breathing.

 

G

 

Hope I managed to get this quote thing to work...

 

I have the Cooke 10.4-52mm and I can confirm it's par focal and does not breathe (not enough for me to really notice at least, but I do no VFX work). For me it's nice to have a zoom since it makes focusing easier when I zoom in to focus (and then zoom out for wider focal lengths). When shooting Super 16 I usually judge focus by eye and with wider lenses it can be really hard for me without the zooming.

 

Maybe 10.4-52mm isn't long enough for your planned shot, but I wanted to take the opportunity to recommend this beautiful lens!

[David Mullen ASC]

As a general rule, you'll find that the greater the zoom range, the worse the breathing will be. That's not always true but it happens often enough to be a good guide. Back when I shot 16mm regularly, I always remember being disappointed that the old 16mm Zeiss zoom breathed so badly, and the front end would trombone in and out during a focus rack, making it hard to use a matte box -- because otherwise it was a very sharp, snappy zoom.

[Kenny N Suleimanagich]

The macro feature on that lens is also excellent. It makes up for the unremarkable close-focus.

[David Peterson]

Was curious on experience with various lenses on super 16mm. I was planing on using a Zeiss 11-110 Zoom on a shoot with a long slow zoom shot. but apparently I have heard the lens breathes during zooms and won't hold focus? Are there any zooms that won't be a problem.

 

(When I say breathes I don't mean the subtle zoom effect created by pulling focus but instead the loss of focus while zooming...the opposite effect I suppose)

 

You're using the wrong terminology, you mean "parfocal" not "breathing".

 

https://en.wikipedia.org/wiki/Parfocal_lens

[David Mullen ASC]

Yes, re-reading the original post, he wasn't talking about breathing but about holding focus during a zoom. Cinema zooms are parfocal but if the back focus is off, then even a parfocal zoom won't hold focus as you zoom in and out. So the Zeiss 11-110mm should hold focus during a zoom unless there is something wrong with the back focus.

[Dom Jaeger]

The only cinema zooms I've ever seen that aren't parfocal are converted stills zooms like the old Canon telephoto ones,150-600 etc. Anything designed for cinematography, even the ancient Som Berthiot zooms with optical compensators, will have been designed to be parfocal. Of course some zooms hold focus better than others.

As many have mentioned, an accurate back focus setting is crucial for a zoom to hold focus, but there can also be other causes for a zoom to drop out. All cine zooms will have a curve that can be mapped of how the focus drifts through the zoom range, which can also vary depending on the direction of the zoom travel. The curve can be mapped with an auto-collimator, and if it remains within the manufacturers specifications (something like plus or minus 0.01mm of equivalent back focus), then this drift will go unnoticed in the real world. But over time, as parts wear or get damaged and lubricants dry out, the carefully calibrated focus curve can go out of tolerance. In this case there may be a portion of the zoom range where a focus fall-off becomes noticeable. Unlike the issue of back focus, where a zoom will progressively lose more focus towards the wide end, a wear or damage related problem can cause a loss of focus anywhere in the range.

The Zeiss 11-110 has a sprung zoom follower, which tends to cause less permanent wear damage to the zoom cam, but can become itself a bit stiff over time. I've also had a few cases with this zoom where humid environments have caused sliding assemblies to gum up so that a quick zoom will go briefly out of focus. But generally they're pretty good at holding focus even after a while without service.

 

In terms of breathing, which is an altogether different thing as many have noted, but happens to be the thread title (so people may end up here after a search looking for that), the best 16mm zooms for minimal breathing I've come across are the Cookes (10-30, 10.4-52) and Canons (7-63, 8-64).

[Kenny N Suleimanagich]

I had a 10-100 Mk ii - the direct predecessor to the 11-110, which had this issue of the zoom cam slipping causing a loss in focus. A servicing immediately resolved the issue, a reminder that these 20+ year old lenses do need a proper adjustment before being tested for parfocalness.