The Move To HDSLR And Creation Of A 38mm-768mm Lens

Posted by ToddJones on May 27, 2011 at 10:28 PM

Teton Gravity Research has been exploring digital cinema since we first got a RED One camera 4 years ago. Until that point we had shot everything we did on film. The RED showed us that digital cinema was in fact the future of film making. For the next 3 years we shot all of our projects as a mix of film and RED.  In August of 2010, we went down to New Zealand to shoot 3 broadcast commercials for The North Face for the 2011 X Games. We decided to forgo film cameras and bring our one RED and a bunch of Canon 7D’s and 5D’s. The experience was life changing. The flexibility of the HDSLR’s and their incredible cinematic picture qualities was mind blowing.

Film meets Digital Cinema

Our next project was for Ford Explorer in November of 2011. We were tasked with shooting 3 webisodes and a national broadcast spot in Steamboat Colorado. We decided we would shoot the entire project on Canon DSLR camera’s. The results were once again incredible. These cameras truly are game changers. We were sold on the HDSLR Revolution.

Ford Explorer Commercial shoot car mount.

Next, we began planning to shoot our 2011 feature ski and snowboard film “One For The Road.” For 16 years this annual film had been shot primarily on film.  We had 5 Arriflex film camera packages ready to go for the winter and a bunch of film stock in the fridge. However, we decided it was time to make the switch to digital cinema. We spent months researching the best setups for us in the winter environment. There were lots of issues to address such as lenses, frame rates, viewfinders, support and rail packages, etc. In the end we built 7 Canon 7D packages outfitted as digital cinema cameras. The next challenge was to get out there and figure out the nuances of these new cameras.

We had two unique challenges that we had to face. One was filming hand held from a helicopter in Alaska with a very light camera with a unique form factor. The other was the need to have a very wide to long lens. Typically, we had been shooting an Angeniuex 16mm 12-240 lens. This is roughly the equivalent of a 24-480 in the 35mm world. This lens has allowed us to get super long shots of athletes skiing big and dangerous slopes from a spot where the camera would be safe. The big zoom also allows the flexibility of adjusting framing from very long distances while trying to be light and move fast in the mountains.

We also need a zoom that goes from very telephoto to super wide, so we can reveal the magnitude and size of the mountains the athletes ride as they finish skiing the mountain.

TGR Rider Ian McIntosh drops into an unnamed and unridden peak in Alaska

The problem we faced though was that no such  lens existed in the HDSLR world. We spent months trying different adapters, lenses, doublers, and support systems. We had to modify and machine different parts to create a lens that would cover the APC sensor of the 7D.  In the end we succeeded and created the ultimate AK Big Gun Lens, with a custom mounting bracket.

The TGR AK Big Gun Lens setup

Essentially, this is a Bayonet mount Angenieux 16mm 12-240 lens with a Bayonet Optex Doubler, a bayonet to PL converter which is connected to an EOS to PL mount connected to the Canon camera. The lens is very heavy, so we custom machined a lens support that connects to the bottom part of a Redrock microLensSupport. The lens and the bayonet mount each require some custom machining as well. On the Canon 7D, with the 1.6 crop factor this lens becomes roughly a 38mm-768mm Lens.  With the doubler this lens looses two stops so it goes from a T3.5 to a T4.8.  This is not a fast lens, but we are using it outdoors for action sports so shooting at T5.6 and above is not a problem for us.  The lens is a little softer than a super sharp modern Canon lens, but we see this as a good thing. You should not explore this path if you are not familiar with these older Angenieux lenses, as they are not the same as a $30,000 modern version of a big zoom. It has a very filmic look and we theorize it has less aliasing and moire issues due to this subtlety. When I say it is softer, I am not talking about shots being out of focus at all. They look really good.  Since we have gone through the process and have the supply chains lined up, we are willing to sell one of these for $4,500 USD. This is not a business we are trying to start, we simply feel like we want to be able to help someone who wants this lens get it if they can’t create it themselves. We have learned so much from blogs like Vincent Laforet and Phillip Bloom, that we feel the need to pass some of our knowledge along. We work in wild environments and have developed a bunch of cool stuff to make our gear work in remote locations.  The process takes time so delivery on an order is around 30 days. Our process is to find and test an adequate Bayonet Angenieux 12-240, then we send the EOS to PL mount, the lens, the PL to bayonet converter and a doubler  to our machinist for final fitting. We then get the lens back, test it. We test against existing mods that we have shot with for the last six months and are very happy with. We are not lens specialists, far from it, but we were able to solve a huge problem in our HDSLR workflow and we are willing to pass that success on to other people. You can mount an HR Angenieux 25-250 T 3.5 directly to a 7D with an EOS to PL mount without any of this headache, but the lens is $29,000. We think this is an effective low cost solution for HDSLR users.  You could definitely create this lens yourself for cheaper if you take the initiative.

Here is some sample footage from the lens. We are currently in production on our film One for the Road, so I can’t release all the A shots we have gotten with the camera. I was able to release a few, but I also added some of the older 16mm shots we have gotten with the lens to showcase the type of footage we shot in the past and why we wanted to duplicate this lens on the HDSLR’s.

What you get for $4,500

-An Angenieux bayonet mount 12-240 16 mm lens

-A Optex Doubler

-A bayonet to PL converter

-A EOS to PL Converter

-A 15mm redrock lens support with the custom support bracket

-We will ship the lens completely assembled and tested

Email brian(at)tetongravity.com for more information

TGR Long Lens guru Dustin Handley operating the weapon

Gear discussed in this post:
Canon EOS 7D SLR Digital Camera (Body Only)
Canon EOS 7D SLR Digital Camera

  • tate

    hows the 7D working out when it’s not on the sticks?

    • Todd Jones

      We are usually on some kind of mount, but when we do go handheld it is good if you have the right lens. The canon 16-35 is a good handheld lens,

      • Todd Jones

        Tate, I will be putting up a post soon that walks you through our hand held heli setup. We were very happy with it and will post photos and videos for you to check out next week.

  • Nick

    Have you had to work to get smooth zooming when working with HDSLRs, or do your guys just have super smooth hands?

    • Todd Jones

      Nick, we do use the Canon L glass like the 70-200. We add a redrock xoom stick to a lens gear to help it out. However, the still glass is not meant to be zoomed. That is another reason we wanted to get cone glass on the 7D. The cine glass is much easier to zoom with. Adding a zoom stick helps as well. The shots in the video are all hand zooms and yes we do practice our zooms a ton. Having the right gear is only part of the solution.

      • Todd Jones

        Nick,
        Here is the RedRock zoom stick that easily attaches to the lens gear.
        http://store.redrockmicro.com/Catalog/DSLR-microFollowFocus/nanofocuszoomlever

      • Frank Suero

        Can you please help me here.  I am thingking in getting 2 Angenieux, a 9.5 to 90 and a 10-150.  I know those 16mm lenses does not cover the sensor on a 7D but how much we will loosing, for example on the 9.5 to 90 how much we will loose of the wider openingThanks in advance for your help

  • Landis

    What kind of sticks are you using at such focal lengths? Or even with your 70-200?

    I am contemplating a Sachtler FSB 4 for 7D/telephoto work in the Chugach…do you guys have any experience with them?

  • Hank

    what math are you doing to come up with 768mm? if it’s a 16mm lens doesn’t the effective focal length get shorter when exposing a larger area? would a 12-240 16mm lens become a 8-120 zoom? or did you mean to say that this lens came from a 70mm system. something is weird here

    • http://www.facebook.com/people/Todd-Jones/631681506 Todd Jones

      Hank,
      I am not sure of the math, but the lens on a 16mm camera originally was a 12-240. When you compare the lens on the 16mm camera to a 35 mm still camera it essentially was similar to a 24-480mm lens. I do not know why that is, but this is the reality of the lens. We were not able to get the 12-240 onto the 7D and we believe it would not have covered. When we did get the lens on the body it was with a doubler, so the lens itself was now a 24-480 as a 16m lens. What we learned was that the lens carried it’s original focal length with it and was performing as it had as a 16mm lens. Then you add the 1.6 crop factor to it and it became a 38-768. I do not understand the properties of the lens that made it do this, but we have built 3 of these for our productions and these are the results. I do not know the exact length of the lens now that it is modded, but it is close to this. Our math is simply to allow the lens to keep it’s original focal length and apply the doubler and the 1.6 crop factor to it as this is how it carries. Another thing to note was that when we used to use this lens on a 16mm body it was the equivalent of a 24-480 on a 35mm Canon camera. For whatever reason the glass on a 16mm is longer than that of a 35mm lens. We had done rough comparisons with still photographers who were standing next to us over the years with the 5D and they would need double the glass to get our frame.
      Hopefully someone who is a technical lens specialist can tell us exactly what we have and why it works this way. What I do know is that this lens has worked very well for us and allowed us to continue to take one of our main lenses that we had used in 16mm film and translate it to the Canon 7D.  Great question though and it makes me realize how complex this is.

      • http://www.facebook.com/people/Todd-Jones/631681506 Todd Jones

        Hank, Here is a piece from a thread on reduser that discusses the difference in original frame size
        “The main difference between 16mm lenses and 35mm lenses is the size – to
        cover the 35mm frame those lenses have to be physically considerably
        bigger. Another thing is that since the frame itself is about ~2x
        smaller than a 35mm film frame the focal lengths change. When in 35mm
        film a “normal” lens is 50mm, then the same field of view on 16mm film
        can be achieved with a ~25mm lens (50/2). Another thing to consider is
        that smaller sensors gain depth of field over larger sensors(ever think
        about why all the point and shoot cameras with tiny sensors have
        extremely deep depth of field :ninja: ). So if you have a 25mm lens on a
        16mm camera set at f4.0 and next to it you have a 35mm camera with a
        50mm lens set at 4.0, both cameras get the same field of view(roughly),
        and the same amount of light, but the depth of field will look
        different. the 25mm lens will look like the 50mm lens set at f5.6,
        except it isn’t darker if you can follow what I’m saying. What I wanted
        to say is that on a 16mm sized sensor you lose about 1 to 1.5 f-stops of
        depth of field compared to 35mm cameras, but only in depth of field,
        not loss of light.”

        Here is the full thread:
        http://www.reduser.net/forum/archive/index.php/t-26607.html

        Agin, the big thing is that for whatever reason this lens carries it’s original 16mm FOV with it.

        • http://twitter.com/Mitch_Gross Mitch Gross

          Perhaps this can help you understand the concept:

          http://blog.abelcine.com/2010/05/14/a-lens-is-a-lens-is-a-lens/

          • Hank

            ahh, i see, I forgot that focal length always is constant, so with the doubler it looks like a 480mm on a 35 film plane and 960mm on a 16mm film plane, the APS sensor splits the difference. Now i got it thanks

  • Athan

    Very cool Todd. Looking forward to seeing the film and the use of this lens and the dslr heli footage.
    When does the trailer drop?

    • http://www.facebook.com/people/Todd-Jones/631681506 Todd Jones

      Athan,
      The trailer will drop mid summer. We are still weeding through tons of footage. I will be putting up a post on our heli setup soon. The shots looks great though.

  • http://www.facebook.com/KarlTheBest Luis Antonio Guerra

    Great job, Todd.
    We have some nice 16mm lenses in my university but we are not allowed to modify them, is it possible to achieve an adapter for the EOS mount without modifying anything?
    Greetings from Bogota, Colombia,

    Luis Antonio Guerra.

  • http://www.facebook.com/people/Todd-Jones/631681506 Todd Jones

    Luis,
    Most 16mm glass goes too deep to put on a Canon DSLR, so you would have to modify the lens or modify the camera body. We do not touch the camera. The mod we are doing is on the lens, the PL to bayonet converter and sometimes the doubler. Also, most of the 16mm lenses we had were not modifiable to this setup. Really only the Angenieux 12-240 worked. This was fine, because that weas the lens we could not find anything similar for for the DSLR’s. The Canon L glass has been working good for other scenarios.

  • Charlesanson

    Is there a way to mount one of Canon’s 16x or 20x lens that mount to a Canon XL camcorder to a 7d or t2i 0r t3i?

  • Ryan Farnes

    Are you able to link to the components that you use?  The converter and doubler?  Perhaps even the lens “rings” or whatever you call that thing supporting it.

    I have the angeneiux 12-240 from a ways back…waiting for RED’s Scarlet…  %$#!

    But I would love to put it to use on my Canon.  Finding these rare 16mm lens conversion parts and doublers has been a nightmare.

    Any tips?

    • Todd Jones

      We can sell you one. We put months into ours so we have dialed it in and figured out all the issues.

  • Ryan Farnes

    Whoops.  I see the list of equipment. (sorry, read this post when it came out, just revisiting it.

    Where do you go to buy those items?

    • Todd jones

      We make some of them and sourcse others from around the country from various different people.

  • Frank Suero

    Can you please help me here.  I am thingking in getting 2
    Angenieux, a 9.5 to 90 and a 10-150.  I know those 16mm lenses does not
    cover the sensor on a 7D but how much we will loosing, for example on
    the 9.5 to 90 how much we will loose of the wider openingThanks in
    advance for your help

  • Joel Lovell

    Hello Todd. This is Joel Lovell, we spoke briefly earlier, and I appreciate your sharing your thoughts on the DLSR camera equipment. I did find an interesting article which compared the 60D and the 7D and it appears that there are a few good reasons to stick with the 7D. Here it is, if you are interested: http://dancarrphotography.com/blog/2010/08/27/canon-60d-vs-7d/

  • Anonymous

    Hi guys
    That mod to the Angenieux bayonet mount 12-240 16 mm lens looks great.
    I have a couple of questions:
    Will it work without the doubler and can the doubler be easily added when required?
    Does this lens work on the RED and Epic?
    Regards
    Peter

    • Todd jones

      Peter, we are testing on epic right now. More in a week or so.

  • masaki sekiguchi

    Hello Todd,

    My name is Masaki Skeiguchi, and we ‘ebis films’ have been producing ski & snowboard film in Japan for more than 10 years, by using 16mm film.

    We also thinking about using 7D this winter.

    One queistion, what type of PL-EF mount adapter do you use, MTF, ZUNOW or other?