B4 Mount

[Andrew Benz]

We put the B4 mount on the Red One Lens mount today and shot some quick tests... we Used a Fuiji HD B4 zoom and Im glad to announce we have a very, very healthy optical margin around the 2k windowed frame...

all you who plan on using your B4 lenses.. today was a good day for you.

Yup but taking this:
http://red.com/formatoptions.htm

...I wouldn't say so. However, maybe Rob may enlight us!

Hi E.,

That's what I thought as well, but Stuart English mentioned at dvinfo.net

At least until there is a B4 mount, using B4 lenses with an adaptor like this -

http://www.zgc.com/zgc.nsf/product/C...256EC9005F5789

- will expand the B4 lens coverage to Super 16mm. So your choice of Super 16mm or B4 for 2K RAW or 2K RGB; or cropped slightly, 1080p or 720p RGB.

So, has RED developed a b4 adaptor similar to the Abakus 132 Converter (Converts 2/3 inch Video Lenses to Super 16 Format) to give us the 2K windowed and all the benefits of such? If so, hello 2K with the b4 converter.

 

[Emanuel A.]

Hi E.,

That's what I thought as well, but Stuart English mentioned at dvinfo.net

See my edit if you wish. I am a little bit tired after a long long journey today.

 

[Emanuel A.]

See my edit if you wish. I am a little bit tired after a long long journey today.

Here is:

Yup but taking this:
http://red.com/formatoptions.htm

EDIT -- 2K windowed is not 2K scaled, so there aren't the benefits of downsampling. Only less than a quarter of the full S35mm sensor or 35mm/4K capability. Working as a 16mm camera. Still, you'll need for S16/16mm or B4 mount lenses if you want to go wider. The magnification factor will compromise the 35mm glass use, unless for tele purposes (@FOV level). But without changes @DOF. Although the 2K windowed DOF will surely be different than from the 35mm/4K format.

Not my ballpark, anyway.

Sports can go well. But not so wider or cinematic (4K compared). Even with the proper S16/16mm or B4 mount dedicated glass, wider yes. Apart the 35mm shallower DOF style. And nice for ENG/EFP and one-operator-show style 'cause the deep DOF properties. However, even for sports and following the sport photography, it doesn't seem that we can assume a deep perspective preference -- targeting its core point-of-view. Given by the shallow DOF and not for its opposite. The imaging craft (it doesn't matter where) is always a balance from all you can get. (from) More. Not less.

 

[Corrado Silveri]

Great news! And thanks, Jarred.
There is any possibilities to see the full resolution frame?
And, again, can you please specify the model/manufacturer of the lens?

Thanks again,
Corrado.

 

[Martin Drew]

Hi Jarred

Thanks for that. I am very inerested to see how a B4 lens performs on the RedOne. Which Fujinon lens did you use?

How consistent was the coverage of 2k throughout the zoom range, It must fall off towards the wide end, particularly on a wide zoom. The frame that you posted is the full sensor so I imagine the focal length must have been 50 - 60mm ish. It would be great to see a frame from the widest end of the zoom, that would be really useful for judging worst case coverage.

Any chance of posting one of the frames at full res? If you have a wider shot that would be ideal, it may give a better picture of how a B4 HD lens is going to perform in everyday use.

Martin

 

[Corrado Silveri]

Sorry guys,
just a question: the B4 Mount is the 2/3" Bayonet type standard for the Panasonic Cameras?
Trying to find description on the web...

 

[Martin Drew]

The B4 mount for 2/3 inch cameras was originally used by Sony, but it became the standard and is now used by pretty much everyone including Panasonic.
M

 

[Corrado Silveri]

Thanks Martin,
the doubt coming because "B4" it's not mentioned in the tech specs of ours Panasonic AJ-HDX900.

 

[Jarred Land]

So, has RED developed a b4 adaptor similar to the Abakus 132 Converter .

That abakus is what we used.. its an optical coverter, it uses (i believe) 2 elements and by guesstimation i would say it lost just under a stop of light.

The Lens was a Fuji HA13x45 1.8 lens. The zoom range is 4.5-59mm.

 

[donatello b]

does it change the zoom range ? (field of view - as in does 4.5 remain 4.5 or is it it muliplied by Y x 4.5?)

 

[Martin Drew]

Ahh that explains it. the Abekus will magnify the image by a factor of x1.32 (hence the name).

Elcurado. The HDX900 does use B4 mount lenses. they probably don't mention B4 because the mount is so standard.

M

 

[Martin Drew]

Jarred.

Did you try the built-in 2x converter as well? Interested to know if that would fill the 4k frame or vignette slightly. You would lose a few more stops, but you could get them back again if you downrezzed to 1080p. Potentially you could eek out a bit more resolution this way.

Martin

 

[Steve Gibby]

great news. thanks jared. out of curiosity..was the RS232 connector enabled for use of the zoom servo for the lens?

RS232 isn't necessary to power zoom servos on B4 2/3" zoom lenses. You merely need battery power to the lens, supplied by one of RED's 12 volt auxiliary power outlets and a simple multi-pin connector to match the brand of lens you're using (Canon, Fujinon, etc.). You could also power the zoom servos by an external battery on your tripod or brace, using the same multi-pin connector.

Newer B4 2/3" HD lenses have RS232 circuits to enable all the "smart" features of the lenses, but RED One is a manual camera and will not be able to use those features. Affordable used B4 2/3" HD lenses, without "smart" features will be the best choice for use on RED One. Underneath the lens servo motor there is a switch to change between servo zoom and manual zoom. All focusing and aperture changes will be manual.

 

[Emanuel A.]

I'd add since we'll have a non-expensive RED compact zoom, we'll go well. If not, an affordable used B4 2/3" HD lens would be an excellent deal. And it will be for ENG/EFP style use, anyway. Even if @2K sensor's area.

 

[Jarred Land]

Ahh that explains it. the Abekus will magnify the image by a factor of x1.32 (hence the name).
M

yes indeed.. and if we took it with the Abekus 230 converter we could actually go b4 all the way to 4k... non windowed, at the expense of visual image quality loss, and more light loss.

 

[Emanuel A.]

Indeed.

Here is some useful info related, as well:

«BTW, on lenses, beware of the 2/3" video lenses that were designed for 3-chip cameras . . . these lenses need an apochromatic adapter in order to be used properly on a single-chip system without any chromatic shifting or other chromatic aberations. This is due to 2/3" 3-chip lenses being specificatlly constructed to offset for the different focal points that the red, green, and blue sensors have in a 3-chip camera.»

~ Jason Rodriguez in dvxuser.com [LINK]

 

[Steve Gibby]

Indeed.

Here is some useful info related, as well:

«BTW, on lenses, beware of the 2/3" video lenses that were designed for 3-chip cameras . . . these lenses need an apochromatic adapter in order to be used properly on a single-chip system without any chromatic shifting or other chromatic aberations. This is due to 2/3" 3-chip lenses being specificatlly constructed to offset for the different focal points that the red, green, and blue sensors have in a 3-chip camera.»

~ Jason Rodriguez in dvxuser.com [LINK]

Good point Emanuel...

The Fujinon HA13x4.5 wide angle lens that Jarred is using is an ENG/EFP zoom lens designed for 3 chip cameras. As Jarred mentioned, he's using that lens with an Abakas 132 converter, probably to solve the issues that Jason mentioned in his post. RED hasn't announced the exact technology of their B4 2/3" mount/adaptor/converter, so it is feasible that they may design a converter similar to the Abakas. I'm sure RED is aware of the tech issues for using B4 2/3" HD ENG lenses with RED One.

 

[Jarred Land]

absolutely Gibby... the addition of the elements in-between help offset the CCD issues.. and gives the Mysterium sensor a more balanced image to capture.

We havn't ruled out a non-optical element solution yet.. We just wanted to make sure the current solution will work on the Red camera for those who need to have B4 mount support out of the gate.

 

[Blair S. Paulsen]

B4 support

B4 support

Big shout out for jumping on the B4 mount issue, even to the point of wanting to support it right out of the gate - WOW. Once the Red 18-85 Zoom is in my hands the B4 lens will work a lot less but it would be a huge piece of the puzzle for me in this first year of the Red.

What about the comparison between the windowed Mysterium/Bayer and a 3-CCD camera in terms of image quality? If the RedOne gives me more dynamic range (11 stops has been discussed) and offers me a RAW color space for grading I feel pretty good about the RedOne's ability to win that one easily.

 

[Scott Webster]

This is great news Jarred. This is the Abakus adapter that the Red team have trialed:

'Abakus 132 Converter Product Code 120

This is for the direct optical conversion of 2/3" video lenses into super-16 format. The stainless steel B4 mount at the front of the unit fits onto the rear of B4 mount video lenses. The rear of the unit interfaces with super-16 cameras using an Arri PL mount. Between the mounts is a system of high quality optics, so there is no loss of quality. The unit maximises the use of video lenses for cine super-16.'

Do you think there has been any compromise on image quality by using the Abakus?

The ability to use B4 lenses, HD Cine or HD ENG, with the benefit of the 2K window that allows the longer record times on Reddrive:

2Kx1080 RAW @ 24p - 6.4 MB/sec - about 9 hrs
2Kx1080 RAW @ 25p - 6.7 MB/sec - about 8 1/2 hrs
2Kx1080 RAW @ 30p - 8.1MB/sec - bit over 7 hrs
2Kx1080 RAW @ 50p - 13.4 MB/sec - about 4 1/3 hrs
2Kx1080 RAW @ 60p - 16.1 MB/sec - about 3 1/2 hrs

This really does open the Red up for endless possibilities as a production camera. 2K wedding coverage anyone?