hvx200 doesn't breathe

[dolph2000]

why is that $5000 HVX does not breathe and why does a 10k lens does?
what the main differance in lens structure what causes breathing.

[dolby]

The HVX lens would probably breathe if there was a $50k out there to buy for it.

[smelni]

Internal lens structure can control the breathing

[Mac]

Zoom lenses are pretty amazing things actually, and we tend to take them for granted... Not too many years ago a professional DP wouldn't even consider using one because they lacked contrast, had poor resolution and, unlike primes, breath.

Most prime lenses (excluding some WAs) focus by moving the lens forward and backward in a chunk, like a magnifying glass, to focus the image on a fixed plane..

But a zoom lens has to move the elements inside the lens, in relation to each other, in order to achieve focus on a fixed plane - because of this complex internal movement, the focal length of the lens varies slightly at different focus points, and that's what causes the breathing.

The number and relationship of the elements is greater on a long focal length lens (a lens that goes from wide to extreme telephoto), so on any lens with a ratio greater than say 6:1, a lot of science and R&D is needed to make the thing work at all.

The HVX has a much shorter zoom range than the 17x plus lenses on 2/3" cameras, so that gives it an edge. Added to that is the fact that the cameras are produced in fairly large numbers, so the R&D can be amortized out over the production run, keeping the production cost of the lens down.

Sorry for this long dissertation, but I'm getting kind of tired of all the grousing about breathing...

[PaPa]

would someone be able to show a visual example of this "breathing"

[Brad Neal]

Mac,
Thanks for that detailed explanation.

PaPa,
I don't have a visual to show you, but think of it as zooming. When a lens breaths, it appears that you are zooming in or out as you focus.

This really complicates things when attempting a rack focus.

-Brad

(Added after my original response)

Here is an example of breathing vs. no breathing taken from another thread on this forum:

Here is a demo of the breathing from the fuji 17x7.6 CAC HD lens:
http://www.dvxuser6.com/uploaded/23459/1195861763.mov


Here is a demo of "choking" the fuji 17x7.6 CAC HD Lens in the exact same set-up & focal length:
http://www.dvxuser6.com/uploaded/23459/1195861984.mov

[Mac]

Sorry to go on and on, but something I left out of the above boring lecture...

Breathing probably exists equally at all focal lengths, say 6mm of difference when focusing from 3 feet to 15 feet ...

6mm difference is very slight at telephoto settings - the difference visually between 100mm and 106mm is hardly noticeable.

Take that same variation and apply it to a WA or normal lens and suddenly you have breathing, because the difference between 10mm and 16mm is a lot - it's actually a whole prime lens different on a 16mm film camera...

The HVX, because it's a 1/3" camera, has such extreme depth of field that you would hardly ever follow focus below medium to full telephoto.. because of that, breathing hardly ever presents itself as a problem...

2/3" lenses have shallow DOP, so racking focus often occurs at wider settings, resulting in more noticeable breathing...

[Icarus2005]

the HVX lens is made by lieca, a company that has no higher end lenses that mount on the same camera to protect.

the other companies want to protect their high end products just like panasonic wants to protect its varicam.

its that simple

[mikkowilson]

That's bull. Most companies don't worry about "protecting" the higher line ... especially as in most all cases, more money is made by selling more of the lower end products than the fewer higher end units.

I'm sure Panasonic makes LOADS more on HVX200 sales than Varicam sales. What is there to protect?

- Mikko

[dolph2000]

Even high end lenses breath a lot. I saw some very expensive lenses breath like a running horse. I do lot for Dutch News and they use the high end lensesen you see breathing a lot. It has more to to with zoomlenses than expensive or less expensive lenses I think.

[PhantomVideo]

So can you turn choking on ? sorry we just got a 502 with that lens :)