Does the lens for Fixed 2/3" Scarlet hold its focus while zooming?

[Biao Fan]

As my title says, I wish to find out if the lens for the 8x Fixed 2/3" Scarlet holding its focus while zooming like those pro cine zoom lens or not holding it like the DSRL zoom lens? Any one knows it?

[Jay Gannon]

No-one knows yet.

[David Rasberry]

These are pro digital cine cameras. I would expect it will hold focus through zoom just like any other fixed lens video camera in its price range. Nothing else makes sense.

[Guillermo Freige]

As my title says, I wish to find out if the lens for the 8x Fixed 2/3" Scarlet holding its focus while zooming like those pro cine zoom lens or not holding it like the DSRL zoom lens? Any one knows it?

Slightly off topic, but panfocal DSLR zoom lenses hold focus during zoom. Many premium zooms are panfocal designs.

Guillermo

[Steve Gibby]

Biao,

Consider this comment just two days ago from Jarred concerning the fixed lens Scarlet:

“the motors are in the lens, both autofocus, iris and zoom. That 8x lens all by itself is a technical achievement all by itself. And remember this is a cinema lens.. with custom actuators and lens group movements designed for both motion and still.” http://reduser.net/forum/showthread.php?t=45431&page=3

BTW - the notion that 35mm still zooms can't hold focus throughout a zoom is only true for certain lenses. There are many 35mm still zooms which hold focus quite well throughout zooming, including but not limited to those of parfocal design. There are multiple Nikon and Canon zooms, some even 20 years old in design, which hold focus well throughout a zoom. There are also many newer technology 35mm still zooms which hold focus well throughout a zoom. How do I know this? I've been using 35mm still zooms extensively on my multiple Red One cameras since September 2007 - and I would hazard a guess that I've used them longer and more extensively than anyone you will find.

Back to the Scarlet fixed. I expect the zoom to be superb - to hold focus throughout a zoom, to have minimal breathing, and to have very little CA or aberrations of any kind. In short, the lens will be a great lens perfectly matched to the camera. When Red makes the 2x extender and full zoom through wide converter, which they mentioned at the very beginning of the Scarlet announcements, they will also be perfectly matched with the 8x zoom, and thus really further unlock the creative potential and utility of the camera.

Fun times ahead...

[Biao Fan]

Steve,

Thanks for your reply, "panfocal design" is something new for me, actually I have just finished a feature film using a set of Zeiss ZF nikon lens with a Sigma 24-60 2.8 zoom lens, and this Sigma lens does hold its focus when zooming. can you please list a few commonly used nikon lens with panfocal design for me? For example are 24-70mm F2.8 and 70-200 F2.8 manual iris full frame OK for our purpose? I can't find any info through google on this.

[Steve Gibby]

Bio,

Some of the Nikon and Nikon mount zooms I regularly use on Red which hold focus throughout a zoom are:

Tokina 11-16 f2.8 (with Nikon mount), Nikon 14-24 f2.8, Nikon 17-35 f2.8, Nikon 24-70 f2.8, Nikon 80-200 f2.8 AF (push/pull), Nikon 50-300 f4.5 AIS

On Red I regularly also use my stock Canon 150-600 f5.6L zoom, with Century PL mount conversion - and it holds focus perfectly throughout a zoom. Its a 20 year old lens. My Nikon 50-300 zoom is 16 years old, and it holds focus perfectly throughout a zoom. My Nikon 80-200 is 13 years old and it also holds focus perfectly throughout a zoom. Beyond that, all the new Nikon zooms I listed above which I use hold focus very well throughout a zoom.

I also have a full range of Canon L series zooms I use on my Canon DSLR. I haven't used them on Red, but on another recent thread on the lens forum here on Red User some other Red One owners who use the Birger Canon mount report that their Canon L series zooms hold focus well throughout a zoom.

The word you asked about is "parfocal", not "panfocal". If you do a Google or Bing search for "parfocal" you'll find many web sites which define the difference between parfocal lenses and varifocal lenses.

[Biao Fan]

Thanks for your advices, Steve!