Birger Lens Mount & Follow Focus

[Erik Widding]

I'm hoping the iris can be rolled seperately from the focus possibly using a second control (Big Knob) so we can pull focus as we dolly thru a change in light.

That is the plan. Should the knobs have a switch that allows them to be dynamically changed in function? (i.e. four position: focus, iris, zoom, locked out)

The Asst. I showed it to last night thought that the "big knob" should have a hinge on the clamp so it can drop directly off the rod without needing to remove matte box, lens support etc. when moving to the Dummy side.

That is a good idea. We will make sure the screw and hinge part are captive. Is it okay for this to require an allen key? or is a thumbscrew preferred?

Will the Big Knob support remote hard wired operation for cranes etc? how far?

Does the Big Know allow us to use our standard Arri whips?

Probably fifty or a hundred feet off camera will be fine. How important is it to support a whip if the knob will work on a long cable and be easily removable from the rails?

Can you talk a little about how much the control stretches parts of the lens travel or moves the whole lens travel to a full circle of the control, About reversing the direction of the control travel re the lens, about repeating the marks when remounting on a lens previously marked, about your idea of ready made marked disks????

Things like reversal, range mapping and knob function, would all be settable from a computer, PDA or remote. The recognition of a lens would be native to the mount. It would be recognized when it is attached.

The exact functionality of what happens with premarked disks, and lens memories, etc, will be determined through interaction on this forum. I do not want to dismiss this, but rather suggest that the important decisions I need to nail down this week relate to anything that requires hard tooling. I encourage the raising of software issues, but will defer comments on many issues until next week.

 

[Erik Widding]

I saw somewhere that it was in 1/2 stops... Is that right ? that sounds like big increments to me. Is there a choice for this? or is it just how the canon lenses works?.

We do 1/2 stops on our industrial product, as it leaves the motor at detents, allows the motor to be shut off. We will enable 1/4 stops in the servo mode. This is a function of the design of the mechanism in the lens.

 

[Matt Uhry]

We do 1/2 stops on our industrial product, as it leaves the motor at detents, allows the motor to be shut off. We will enable 1/4 stops in the servo mode. This is a function of the design of the mechanism in the lens.

Cool, Thanks.

Matt Uhry
www.mattuhry.com

 

[Michael Hastings]

birger mount

birger mount

First of all, Erik great work! Thanks.

As far as position of buttons, video guys are generally used to working camera and lens controls (except zoom) with the left hand - since the right hand usually holds the zoom grip and is the main way of holding the camera. Gain, white balance, power, filter, etc are all on the left side of the video camera.

This is a really good idea. Prior to full integration by REDm this would allow the thing to be used out of the box without adding an extra knob or having any other control available.

I think it would make sense to have three buttons on the unit:

• HOME
• IRIS+
• IRIS-

HOME would open the iris all the way, and would find the zoom and focus limits, and then return the lens to the current knob positions. Which side of the mount should the buttons be on?

Anybody want to comment?

My bad then. Seems a shame that an adapter can't be built that does the autofocus on these lenses though, I suppose it requires the nikons sensor in order to refocus in such a way.

As far as I know, an autofocus system would have to be done by the camera head since it is at the sensor/camera electronics that figures out if it is in focus. If the camera head can figure it out it could then tell the birger mount where to set the focus on the lens - so it wouldn't really require anything new of the lens mount (or lens) itself.

 

[David Nardini]

birger/RED EOS adapter at IBC 2007 ?

birger/RED EOS adapter at IBC 2007 ?

Thank you Birger (& RED !) ... will there be a working EOS unit on show at IBC 2007 ?

 

[Ronnie Silos]

Hi Gibby,

Let me know if I can participate in the LA test at least for the Canon lenses. I have in my bag the following lenses and will be willing to provide for the test if needed.

24 1.4 L, 50 1.4, 85 1.2 L, 135 2.0 L, 200 1.8 L, 16-35 2.8L

Thanks, and thank you Erik!

Ronnie

 

[Steve Gibby]

Thank you for thinking of LART on that! We're still planning out our lens tests. I'll pass your offer on to the team for consideration. If we decide to greenlight your offer, I'll PM you and we'll hook it up.

Thanks again...

 

[tj williams]

Hi Eric,
1. I like the buttons (to change functions) OK but would want to purchase two wheel controls so I could mount a focus left and right and so I could pull iris and focus at once. ( I would hate moving the iris + or - with buttons) Good that you have got the iris down to 1/4 stop increments. If anything can be done to put it fully under smooth variable control it will of course be even more wonderful!!!

2. Re the hinges totally right!! toolless is the way most stuff is going. I like to have an allen recepticle in the middle of the thumb wing nut thing, so if it can't be tightened enough then put an allen T-bar on it.

3. Great to see the crane thing is covered!! I see your point about the whip. My question is two parts?
A. is it worth it because assts. have a whip and are used to it. and the appearance will be more "professional"
B. Can I put a whip in the hole faster than removing the wheel from the rod and replacing the lemo cable with a longer one?
I supposed this has to be balanced against whether or not there is big additional cost to mfg. an arri recepticle in the wheel?

Lens recognition, can the mount really see the difference between the various lenses so exchange the 17/50 for the 80/200 and the mount knows???

RE disk marking etc. software stuff. It would be nice to place this before working assts. Not too many assts. on this forum.

http://www.filmtools.com/camassup.html

sells to a lot of assts. probably they could put you in touch with a bunch of them...

If it turns out to be possible to enable auto focus. then a button on the wheel or re-moted to the RED handle etc that allows soft touch auto focus/or remote to the wheel would be very nice also.... (probably this is like wheeeeeooo I can fly by flapping my arms.)
The auto focus piece for car work etc for film is a pretty steep rental, and is limited in the near distance just where focus is most critical. so it would be a great accessory........

The big black benz squeals around the corner going dark light dark as it passes under the street lights, the driver regains control and barrells toward camera at high speed at the last minute he applies the brakes and comes to a stop with the benz logo filling the screen!

 

[T. Glen Phelps]

Eric,

First let me say, I am very excited about the Birger EOS mount. I have a significant investment in Canon L-series glass and it's fantastic that I'll be able to use it on my RED cameras as well as my Canon EOS rigs. I can't wait to try my 400mm and 600mm super telephotos on a RED.

For iris control, in addition to the remote control you mentioned, I would suggest a cine-style rotating toothed ring (continuous analog) around the circumference of the mount. This would in effect add manual iris control to any EOS lens.

I'm also curious about how manual focus is handled on the 85mm f/1.2L lens since it has a different manual focus control scheme than any other L-series lens. The manual focus ring only works when powered by the camera and it has no hard stops, it rotates continuously.

Thanks

Tracy

 

[Mr. Paul White]

After all, will there be auto focus feature or not?

Please, simple answer for dummies: yes or no?

No...

Is there no way?

 

[chuck colburn]

Erik,

The idea of a split clamp is ideal. (been thinking about it myself for my lowly mechanical FF idea), but what comes to mind is that it will have to be very accuretly machined as any slop will effect the clamping force. This gets to be more of a concern if the unit is going to be using inserts to switch between 15mm and 19mm dia. rods. Mayby it would be best to tell buyers to just purchase two seperate units. lol

Chuck

 

[Finner]

That is the plan. Should the knobs have a switch that allows them to be dynamically changed in function? (i.e. four position: focus, iris, zoom, locked out)

Iris would be better as a slide knob as that is what people are use to with current remotes. I think a wheel is best left for focusing. 2 wheels I could see turning into confusion with pulling focus but in the past I have often done a slide iris change while pulling focus and it seems like the brain can handle those 2 moves at 1 time.

That is a good idea. We will make sure the screw and hinge part are captive. Is it okay for this to require an allen key? or is a thumbscrew preferred?

A thumb or better yet a small arm tightner is a must. Allen key work would take to long at times.

Probably fifty or a hundred feet off camera will be fine. How important is it to support a whip if the knob will work on a long cable and be easily removable from the rails?

A whip is also another must as it is important that an focus puller has the ability to have both hands free at all times so you can change ND's or do other work as soon as a change is made. (examples: a remote FF usually has a neck lanyard to make this possible and you can let go of a whip and leave it hanging at any time and do different tasks. In the case of an electronic knob on a cable you would need to find a safe place to put it down beside the camera and even then it could get knocked or if the director decided to have the camera moved 2 feet a knob with a cable would soon become a big pain in the ass. A whip is simple and works very well for many reasons.)

The exact functionality of what happens with premarked disks, and lens memories, etc, will be determined through interaction on this forum. I do not want to dismiss this, but rather suggest that the important decisions I need to nail down this week relate to anything that requires hard tooling. I encourage the raising of software issues, but will defer comments on many issues until next week.

This will be interesting. If I have the time I will comment on it next week as you address it.

 

[ColinSmith]

Is there no way?

No easy way anyhow....
SLR lenses are dumb, they focus where the body tells them.
SLR bodies also use an autofocus system that depends on there being a mirror there.

It's possible to imagine some basic autofocus system built into the lens mount, but I find it harder to see that approach as usable.
You could also imagine Red putting autofocus on the body, but from the tone of their comments I do not see that as an option they are looking at anytime soon, and it would seem to bring a lot of technical issues in build and usage.

 

[Michael Hastings]

Try to be realistic about on mount controls and autofocus

Try to be realistic about on mount controls and autofocus

First of all, this isn't meant to snipe at anyone, it's more to be informational. In this first quote I think Erik is saying that some ability to adjust iris could be right on the mount (allowing use without the cable/extra knobs and since manual focus and zoom are on the lens but manual iris is not). But we need to try to be realistic: I think what he is saying is that since he already has a small circuit board on the mount for the lens contacts, etc. it would be pretty easy to add three small buttons to the board which could also pass through the mount with very little engineering change. However things like a rotating encoder control - as in the second quote, while nice, is a much more substantial design, engineering, manufacturing task and so probably not realistic as a simple add on to what he has already done (which by the way is very substantial).

Finally, as far as autofocus, we probably need to give it up as far as the lens goes because the determination of focus needs to happen in the camera head, so we need to bug the RED team for that. In other words, the lens mount already has what autofocus needs as far as driving the lens - i.e. tell it where to go and it will go there but the determination of where to go (focus) has to be done by the camera head. So if something like RED's magic focus or a facial recognition algorithm in the RED (facial recognition focus is already in a number of $300 digital still cameras) can determine that proper focus is at 7.5 feet then simply send that command to the Birger mount and it will go there. That is in the current version, so if RED or some third party genius comes up with an autofocus algorithm later, it could be used with the Birger mount quite easily.

PS Think about the fact that none of the broadcast/EFP shoulder type cameras e.g Varicam, F900, etc. have autofocus. I think these cameras should have autofocus by now, but the thinking seems to be that a professional is supposed to be anticipating focus so wouldn't want AF since it is normally reacting rather than anticipating. (I know some AF systems track horses, runners, etc. but I'm talking more about an actor walking from 8 feet to 4 feet, or shifting from one actor to another, and anticipating that focus shift - which is harder for an AF system to do.)

This is a really good idea. Prior to full integration by RED this would allow the thing to be used out of the box without adding an extra knob or having any other control available.

I think it would make sense to have three buttons on the unit:

• HOME
• IRIS+
• IRIS-

HOME would open the iris all the way, and would find the zoom and focus limits, and then return the lens to the current knob positions. Which side of the mount should the buttons be on?

Anybody want to comment?

Eric,

For iris control, in addition to the remote control you mentioned, I would suggest a cine-style rotating toothed ring (continuous analog) around the circumference of the mount. This would in effect add manual iris control to any EOS lens.

Thanks

Tracy

(regarding autofocus) Is there no way?

 

[Don King]

Yes, it's true. I've been working on a 2/3" chip since a long time ago. But the fact is the small 1/3" ones have handled with the auto-focus and there's no evidence on failure tracking subjects.

Red is betting on a new small camcorder. If so, the auto-focus feature should be implemented no matter when. It's only a question of timing.

 

[Steve Gibby]

Because of its primary market positioning as D-cinema, manual camera, RED One hasn't incorporated auto-functions. Getting auto-anything infused into RED One will not be impossible, but will involve workarounds, most likely by 3rd parties.

Conjecture:
The RED Professional Pocket Camera (PPC) may be a different story, targeted at a different market positioning - a hybrid, crossover, D-cinema/EFP market. I have no knowledge of plans for such, but I wouldn't be surprised to see the RED PPC feature user selectability, via switch/button, of some auto-functions, such as auto-iris and autofocus. In fact, I think it would be an excellent utilitarian feature for the PPC - if the PPC is indeed targeted at the crossover D-cinema/EFP market. For a smaller, multi-genre camera to be auto when you want/need it, and manual when you want/need it would spread the utilitarian value of the camera, and thus also it's target market.

-----------------------------

The notion that someone who uses an auto function on a camera, or for that matter uses a camera system that has some auto-function capabilities, is somehow not a professional, is simply not dealing with the realities of a convergent motion media industry, and the increased capabilities of technology. Legions of EFP professionals regularly use certain auto-functions on their camera systems. Manual functions on a camera are fine, and when they're the best choice for what I'm trying to shoot, I'm all for using them. But since I shoot a wide variety of cine style and EFP style productions, there are times and productions (or portions thereof) where certain auto-functions are not only quite usable, but would sometimes be the best choice - if they're available on a camera system.

RED One's technology pedigree is most closely aligned with DSLR cameras, followed by video cameras, and least similar to film cameras. That said, RED's primary target market for RED One is D-cinema (thus an all-manual camera) - with a secondary target market of EFP.

If RED, Birger, or some other 3rd party manufacturer somehow devises a functional method to enable auto-focus on a RED One, I'll adopt it for use in certain genres of production for which it would be useful. If RED designs switchable auto/manual capabilities into their Professional Pocket Camera (PPC), I'll welcome that as an increase in utility for the camera for a wider range of production genres.

I expect RED One to be an excellent camera system and service a broad array of production genre needs - but I'll also keep an open mind for refinements or 3rd party additions that could even further the capabilities of RED One - and I'll keep my eye on the development and proposed features of the PPC.

I seek a balance between tradition and progression.

 

[Emanuel A.]

The notion that someone who uses an auto function on a camera, or for that matter uses a camera system that has some auto-function capabilities, is somehow not a professional, is simply not dealing with the realities of a convergent motion media industry, and the increased capabilities of technology. Legions of EFP professionals regularly use certain auto-functions on their camera systems. Manual functions on a camera are fine, and when they're the best choice for what I'm trying to shoot, I'm all for using them. But since I shoot a wide variety of cine style and EFP style productions, there are times and productions (or portions thereof) where certain auto-functions are not only quite usable, but would sometimes be the best choice - if they're available on a camera system.

My own thoughts/words too. Same POV.

 

[Darwin]

I have High hopes for the Birger Lens Mount. I have the 17-55mm f/2.8G ED-IF AF-S DX and the 70-200mm f/2.8G ED-IF AF-S VR, which I think is one of the best zoom lens Nikon has ever made!

 

[CVB]

Erik, nice work on the adaptor. we'll do our best to get bluetooth into our remote... maybe we can make the transceiver in our remote interchangeable between zigbee (1000m range) and bluetooth (100m range). Worst case scenario we could use the accessory serial port we will have on our receiver and just hook it into the auxiliary port on your adapter then relay the meta data back to the camera through our receiver. There's tons of flexibility in both of our designs and im sure its just going to be a matter of a cable and firmware to get everything working together.

 

[Fergus Meiklejohn]

I have High hopes for the Birger Lens Mount. I have the 17-55mm f/2.8G ED-IF AF-S DX and the 70-200mm f/2.8G ED-IF AF-S VR, which I think is one of the best zoom lens Nikon has ever made!

Does anyone have experience of how the VR function looks when you use this lens on a video/film camera? It was designed for making stills so can we assume that it won't look weird sometimes if we use it on a video camera? (I have no idea.. just asking..)