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The Nikon D5 Review: Roller Derby and Mammoth Cave Testing

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The weekend before last, I had quite a trip planned for my birthday. I was going camping at Mammoth Cave, with a side trip to see some friends play roller derby in Bloomington, IN. I had originally planned to bring only my Mamiya Universal and some instant film for a personal project I’m working on, but with the new Nikon D5 available, I figured I’d have a good chance to really push the camera. The Nikon D5 is aimed right at sports shooters, and I can’t think of any sport more demanding on a photographer than roller derby (I’m very biased on this point). I wanted to see if the new AF features and low light capability would make things any easier for me shooting the sport I love so much. And I thought that the caves would really let me push the low light ability to its limits.

The camera itself is Nikon’s latest flagship, with the build quality we’ve come to expect from their top level series. It replaces the now aging Nikon D4s with lots of tweaks and upgrades. Without getting too technical, there’s a new AF system with more focus points, greater detection range, and auto AF Fine-Tune, a higher resolution sensor, a wider ISO range, improved metering, higher burst rate, bigger buffer, dual XQD slots (we won’t be carrying the CF version here at Lensrentals, but it’s an option if you’re looking to buy), a higher resolution LCD screen that’s also a touchscreen, more efficient use of the EN-EL18a battery, 4k video capabilities (kinda), and some minor button changes which make some more commonly used features more prominent than on previous bodies.

In the hands, it feels basically the same as the Nikon D4s, so there’s not too much to get used to if you’re looking for an upgrade. It’s still a big, kind of bulky camera, but if sports or wildlife photography is your business, this is just part of the game. The mode button has moved to the other side of the camera, and there’s and ISO button in its place. And there are some new programmable function buttons. Everything is designed to make it a little easier to find the functions that are most used by this camera’s audience. Did you ever use the flash button on the Nikon D4s? No? Neither did most people, so it’s gone.

So how does it handle? Like a dream! Roller derby venues are notoriously poorly lit, and the action is fast, so with anything less than the best gear, it can be a real challenge to capture what’s going on on the track. For the Frank Southern arena in Bloomington, I was shooting at 1/1000, f/3.5, ISO 12800.

Jammers so fast Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

Jammers so fast
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

Normally I’d be using strobes or speed lights to augment the available light, which usually keeps me down to 1/250 and an ISO of 3200 or 6400. Or I’d be pushing things in post to get good exposures. With the Nikon D5, I didn’t have to worry about any of that. ISO 12800 is clean enough for most things, and I wouldn’t mind 8x10s printed from these files. They look cleaner than my images from WFTDA Champs in 2014, and WFTDA is still using some of those images in their branding and marketing. I shot those on the Nikon D4s and Nikon D750.

This was an emotional jam Nikon D5, 200mm f/2, 1/1000, f/3.5, ISO 12800

This was an emotional jam
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

Tear detail at 100% crop Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

Tear detail at 100% crop
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

AF is also a definite improvement. Tracking skaters was a breeze, even with the slow focusing Nikon 58mm f/1.4G AF-S, which I used from the center track. The Nikon 200mm f/2G ED AF-S VR II is my absolute favorite sports lens, and on the Nikon D5, it really sings.

Even blockers like to fly sometimes Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

Even blockers like to fly sometimes
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

Even the Nikon 20mm f/1.8G ED AF-S locked focus fast on moving subjects. I always have troubles locking on skaters’ faces when they take their victory laps for the fans. Not this time!

Congrats on the win, Gem City! Nikon D5, 20mm f/1.8G, 1/1000, f/3.5, ISO 12800

Congrats on the win, Gem City!
Nikon D5, 20mm f/1.8G, 1/1000, f/3.5, ISO 12800

 

My keeper rate for in-focus images was much improved across the board. I preferred the standard dynamic-area modes, usually sticking with the 72 and 153 point options. I tried group-area AF as well, but I found that it liked to pick the wrong subject most of the time. I was better off selecting my own focus point and having the camera track around that. That seems to be the way it’s always been for me with Nikons. 12 frames a second with AF between each frame was great for getting sequences around the track, and AF kept up with each frame (at 14fps focus and exposure lock and the viewfinder blacks out, so it’s not for tracking).

Teamwork Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

Teamwork
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

Out of play Nikon D5, 58mm f/1.4G, 1/1000, f/3.5, ISO 12800

Out of play
Nikon D5, 58mm f/1.4G, 1/1000, f/3.5, ISO 12800

Is 200mm too tight? Nah. Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

Is 200mm too tight? Nah.
Nikon D5, 200mm f/2G, 1/1000, f/3.5, ISO 12800

 

One amazing improvement that I almost didn’t notice is the automatic flicker compensation when shooting faster than 1/60. The fluorescent lighting at Frank Southern has always forced me to convert everything to B&W to compensate for the lights cycling. In color, I’d end up with frames that were half pink, half green, or half exposed properly and half dark. I didn’t have to do that with the Nikon D5, even at 1/1000. There’s no color shift or anything! It’s a derby miracle! I don’t have to worry about future games under sodium vapor or mercury vapor lights either. I can’t tell you how happy this makes me.

I didn’t really have to push the low light performance too much, even in Mammoth Cave. I mostly stuck to ISO 12800, using the Nikon 20mm f/1.8G. The results are still pretty great, though.

First stop on the Frozen Niagara tour Nikon D5, 20mm f/1.8G, 1/25, f/1.8, ISO 12800

First stop on the Frozen Niagara tour
Nikon D5, 20mm f/1.8G, 1/25, f/1.8, ISO 12800

 

A good overview before going down into the Frozen Niagara area Nikon D5, 20mm f/1.8G, 1/30, f/1.8, ISO12800

A good overview before going down into the Frozen Niagara area
Nikon D5, 20mm f/1.8G, 1/30, f/1.8, ISO12800

 

Various cave features from inside Frozen Niagara Nikon D5, 20mm f/1.8G, 1/25, f/1.8, ISO12800

Various cave features from inside Frozen Niagara
Nikon D5, 20mm f/1.8G, 1/25, f/1.8, ISO12800

 

I did push it to 51200 for a couple of shots. There is always a stop on the cave tours where the guides turn out all the lights to show you how dark it really is down there. Then they take out a lighter and show you their “emergency light”. Locking focus in light that low wasn’t a problem for the Nikon D5. And noise levels at ISO 51200 are pretty spectacular for what they are. Would I push it farther? Probably, but only with careful exposure and post processing. For most purposes, though, I’d never need much beyond 12800.

First time I got the demonstration Nikon D5, 20mm f/1.8G, 1/20, f/1.8, ISO 51200

First time I got the demonstration. Focus locked on the other guy with a camera.
Nikon D5, 20mm f/1.8G, 1/20, f/1.8, ISO 51200

 

Second time I got the demo, on the Domes and Dripstones tour Nikon D5, 20mm f/1.8G, 1/15, f/1.8, ISO 51200

Second time I got the demo, on the Domes and Dripstones tour
Nikon D5, 20mm f/1.8G, 1/15, f/1.8, ISO 51200

 

What I Liked:

  • AF speed, accuracy, and flexibility
  • High ISO noise performance
  • Great image quality

What Could Be Improved:

  • AF points spread to cover more of the frame
  • Obviously, Expensive
  • No need for touch screen

 

I think overall the Nikon D5 is a great camera for the people that need all the bells and whistles, namely pro sports photographers. At a retail price of $6500 this is not the camera for most people, but renting it for a weekend won’t break the bank. For all that money you’ll get marked improvements to AF, noise performance, resolution, and buffer/write speed. I forgot to mention that we did, in fact, test out the buffer on the D5, and I can confirm it’s true. At 12fps, you will get 200 images in the buffer before it fills up. And that’s in raw+jpeg. It’s quite a thing to behold. But you have to have the XQD version to do that. The only thing I didn’t really care about was the touch screen. Yes, it can be useful, but it’s not necessary. After the first couple hours of use, I just turned off the touch capabilities. I foresee myself using the Nikon D5 quite a bit in the coming months, at least until I get to test drive the Canon 1DX II. But that’ll be a blog post for another time.

 

Joey Miller

April, 2016

Hands On With The Panasonic Varicam LT

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Panasonic’s new Varicam LT is basically a lighter-weight, more compact version of their Varicam 35, which has seen relatively wide adoption since its introduction in 2014. Weighing in at 6 pounds (body only) the Panasonic Varicam LT is a capable alternative for applications such as gimbal work or shoulder mounted operation, setups that can be difficult or impossible with the more cumbersome Panasonic Varicam 35. Don’t assume, though, that the lighter weight means lesser performance. With the exception of higher-end codec options that require the larger recording unit on the Varicam 35, the LT is poised to be every bit as powerful and popular as Panasonic’s flagship cinema camera. To really put it to the test, I shot with it for two days in downtown Memphis to see whether or not it lives up to the expectation that the Panasonic Varicam 35 has set.


Panasonic-Varicam-LT-1
Panasonic-Varicam-LT-3

The first thing that impressed me in my time with the camera was the build quality. Firstly, other than the plastic cover for the Wi-Fi module port (presumably for signal strength), nearly the entire camera body is constructed of lightweight magnesium. It’s really important, especially with a camera like this one that’s meant to be used in a run and gun documentary setting, that you don’t run the risk of destroying your equipment if it gets bumped around a little. Plastic camera bodies like the Sony PXW-FS7 are affordable and light, but probably won’t fare too well after a fall. The Panasonic Varicam LT, on the other hand, feels like it could stand up well to rigorous use. All of the buttons on the camera body and control panel are LED backlit, which is a really nice touch that I’m hoping to see more manufacturers implement in the future. If you need to be stealthy or conserve battery power, though, the lights can be dimmed or switched off entirely. Finally, the EF mount features a locking ring, much like the one on a PL mount, which helps secure larger EF lenses. As a side note, the fact that this feature is missing from the Canon C300 Mark II is one of my only major gripes about that camera, especially since the EF mount on the older Canon C500 had one.

Panasonic-Varicam-LT-4

Both the EF and PL mount versions of the Panasonic Varicam LT will ship with a control panel that opens up a variety of setup options while still allowing for management of the camera’s settings and can even be used as a live view monitor in a pinch. The detachable control panel can be mounted just about anywhere and connects to the camera body with a 2-foot cable. For a traditional studio setup, for example, you’d mount the control panel on the right side of the camera, opposite the viewfinder, for use by a Camera Assistant. On a shoulder-mounted ENG-style shoot you might want it on the left, facing the operator. With the camera on a gimbal you could mount the control panel to the top cross bar or even dial in settings before removing it entirely. It’s a really great way to enable flexibility without sacrificing function, and I think it’ll be one of the standout features of this camera. Design-wise, it takes a lot of…I’ll say inspiration from Arri’s control panel from the Alexa and Amira lines, which is a theft I can’t really fault Panasonic for. If it works, why not take it?

Ergonomically, with the shoulder pad, grip module, and viewfinder attached, the Panasonic Varicam LT is among the best cameras we carry for shoulder-mounted operation. The grip attaches via industry standard Arri rosettes and features two user-programmable buttons in addition to a record button and an iris control wheel. It actually looks, feels, and operates a lot like the Sony PXW-FS7 side handle except that it can be adjusted without tools, which I think is a huge plus. The shoulder pad is soft without being pillowy, and is adjustable relative to the camera body, which makes it easier to balance heavy lenses. In my setup, for example, you can see that I have the shoulder pad about as far forward as it would go in order to bring the center of gravity of my camera setup nearer to the center of my shoulder.

Panasonic-Varicam-LT-6

During my two-day shoot, the camera remained remarkably balanced and comfortable even over a long period of time. In fact, I can only think of two negatives. First, the viewfinder bracket didn’t extend far enough from the camera body for my tastes. Even with the viewfinder as far out as it would go, I had to position the camera closer to my neck than the outside of my shoulder, which put the side of the camera body in contact with my right ear. It’s a minor inconvenience, but something that could easily get annoying over the course of a whole shooting day. Second, there aren’t any physical audio controls on the camera body. You have to jump into the menus on the control panel if you want to adjust your input levels. Sure you can map one of the user buttons to get you to the input level menu quickly, but I’d still prefer some physical dials. My guess is that Panasonic assumes that, with a camera in this price bracket, you’re going to be running dual-system sound, which I suppose is fair. I think, though, that if your camera has XLR inputs there should be physical volume controls whether you think they’ll be used or not.

There’s a detailed list of features, codecs, and frame rates on the Panasonic Varicam LT product page, but I’ll give a quick rundown of the highlights here. Most importantly, the camera will shoot UHD (3840×2160) or DCI 4K (4096×2160) at up to 30p in a 10-bit 4:2:2 color space using the AVC-Intra 4K422 codec. Knock that down to AVC-Intra 4K-LT and you’ll be able to record UHD or DCI 4K at up to 60p. Beyond that frame rates vary based on codec, resolution, and sensor crop, but the camera maxes out at 240p in cropped 2K. 4K RAW output is said to be coming with a future firmware update.

Panasonic-Varicam-LT-8

The Panasonic Varicam LT shares a sensor with its larger, cinema-focused cousin the Panasonic Varicam 35. This sensor offers 14 stops of dynamic range in V-Log, which, if you’re unfamiliar is Panasonic’s proprietary log gamma. If you’d like more information on this color space, or log spaces in general, I wrote a blog entry about the subject a couple months back. Another unique feature of the sensor is its ability to shoot at two different native ISOs, a feat accomplished by having two analog circuits for each photosite. In theory, this means that sensor noise and dynamic range should be equal at 800 and 5000 ISO. In practice, while I wasn’t able to do any strictly controlled scientific tests, I found that 5000 appeared a little noisier than 800, though certainly way less noisy than if I had pushed the ISO from 800 to 5000 on a camera with a native ISO of 800. Generally, I think people who need the second native ISO of 5000 for low-light shooting will be very happy with it.

Overall I’d say that the Panasonic Varicam LT will turn out to be a really popular camera for high-end documentary work, episodic television production, or even low mid-budget indie cinema. My minor complaints (limited viewfinder adjustment and no physical volume controls) pale in comparison to the broadly positive experience I had shooting with this system. Below you’ll find a link to a quick edit of my shots from this weekend, including an ISO test. As always, if you have any questions or additions feel free to chime in in the comments.

 

A Look at Electromagnetic Focusing

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If you’re like me you like to know what’s going on inside your camera or lens to some degree. They are tools, and if I want to get the best use out of my tool I need to know it’s strengths and weaknesses.

You may not have noticed, especially if you shoot just Canon or Nikon, but there’s been a quiet change in autofocus motors going on. Or you might have barely noticed marketing-fluff terms like ‘linear focusing’ or ‘electromagnetic focusing’ without really understanding what they meant. Even if you understood the general terms, you probably aren’t really certain how they work, or how they might be better or worse than what we’ve been using.

So I thought some of you might like taking a look into what might (or might not) be a big deal: the changes that are being made in autofocus motors. Today I’m going to discuss linear electromagnetic focusing motors. I may do another post about linear-piezo and ring-to-linear piezo motors later, but those are, so far, less common than the electromagnetic motors.

A Very Brief History of Focusing

Back in the days when ships were made of wood and photographers of iron, you would focus your lens by moving the whole lens (or the whole optical assembly) closer or further from the imaging surface. This worked just fine but it was slow and often a bit clumsy. Later on, lenses were designed so that just one element or groups of elements moved on a linear track with a tooth-and-rail gear. If you’ve ever used a macro rail or shot with a Lomography Petzval lens you’ve done this.

Gear-and-rail focusing knob of a Lomography Petzval lens. Lomography. http://shop.lomography.com/en/brass-petzval-canon-mount

Gear-and-rail focusing knob of a Lomography Petzval lens. Lomography. http://shop.lomography.com/en/brass-petzval-canon-mount

 

Before long someone figured out that it would be convenient if you moved the focusing element nearer or further by just turning a barrel on your lens instead of twirling a knob. This is where the helicoid barrels of which we speak so often came into play. (Helicoids also move zoom elements in zoom lenses, but zoom lenses didn’t come along for many years.) The moving lens element(s) have rollers that pass through the slots in the helicoid barrel. When the barrel is rotated the groove moves the lens forward or backward within the barrel, rotating it as they do.

Lensrentals.com, 2016

Helicoid grooves in a barrel with lens rollers showing in the slots. Rotating the barrel moves the lenses forward or backward. Lensrentals.com, 2016

 

Much later on, autofocus was developed. The ‘auto’ part of that required that the lens has a motor to move the focusing element without any input from the photographer. At first, small, geared direct current (DC) motors were used for this purpose.

IMG_5118s

A geared DC electric focusing motor. Lensrentals.com, 2014

 

In the 1990s, ring USM (ultrasonic motors), which were definitely quieter, faster, and probably more accurate than DC motors, became commonly used.

USM

A ring ultrasonic focusing motor. Lensrentals.com, 2015

 

There have been some other motors used for autofocus. Stepper motors, a type of brushless electrical motor that moves more accurately than regular motors, are used in some lenses for improved focus accuracy (Canon’s STM motors are an example). Tamron’s Piezo Drive uses a non-ring shaped USM to move the focus. It is smaller and lighter than a ring USM, but I’m uncertain if it was better or worse as far as accuracy and speed.

The terminology gets a little confusing here because a ring USM motor is technically a type of Piezo-electric motor. The important thing is that for all of these motors the focusing element moved in a helicoid slot, moving forwards and backwards as the slotted barrel rotated.

Enter the Electromagnet

Some years ago, a few manufacturers began adapting voice-coil actuators (VCA) to move the focusing elements. At first, we only saw these in small lenses, especially those for m4/3 systems, but sometimes found them in lenses from Fuji, Samsung, and a few other brands. We thought they were odd, but other than that we didn’t pay much attention. (As an aside, VCAs are usually what focuses the lens in your cell phone. They can be made small enough to be part of a circuit board.)

Lensrentals.com, 2014

Panasonic Jack-in-the-Box lens design. Lensrentals.com, 2014

 

Voice coil actuators have been around for a long time; driving the loudspeakers in sound systems (especially the sub-woofers), moving the arms of disc drives and DVD players, and a host of other things. They basically consist of a permanent magnet and an electromagnet wrapped around each other in some fashion. Applying current moves the electromagnet along the permanent magnet in one direction. Reverse the current and it moves in the other direction, (You can find a nice video demonstration here). Voice coils have some nice advantages over other types of motors: they are simple, silent, and very fast.

The focusing element in a lens with a voice coil motor is different, too. It doesn’t rotate in a helicoid to move backwards and forwards. It slides directly up and down on a couple of posts inside a small subassembly. It seems simpler to just slide a lens up and down rather than rotate it through curved slots, so you can see there are theoretical advantages to such a system. Of course, like anything engineered, there are usually both advantages and disadvantages in practice.

The Linear Focusing Explosion

If you shoot m4/3, Fuji, or Sony FE mount lenses, you’ve probably at least noticed a marketing blurb here or there about ‘linear’ or ‘electromagnetic’ focusing motors. You know me, I LOVE new technology so when these started coming out I was excited and wanted to read about them. But unfortunately, all I could find were typical pablum marketing blurbs like this:

  • a newly developed linear AF motor which moves the lens elements directly without the need for gears or the drive of other mechanical parts
  • able to snap focus in 0.1 seconds
  • drives lens elements in the non-contact state to deliver silent and highly responsive AF
  • The fast, quiet AF drive with linear motors keeps the subject crisply in focus even when shooting in hectic situations
  • precision, quiet linear motors, and technology inherited from high-end professional camcorders
  • linear AF drive system for quiet operation

I get that the new system is quieter. It does seem likely it’s faster. It might even be more precise. But I got kind of uncomfortable. All I could think of was why if you have this awesome new technology, why aren’t you telling us all about it? Even more, why are you kind of vague in telling us which lenses have which types of the motor?

My paranoia increased when I saw that the linear electromagnetic focusing motors (LEMs) in the Sony FE 24-70mm f/4 and FE 55mm f/1.8 lenses broke a lot. So I decided we should poke around in some of these new lenses and see what we could see.

Single LEM

Type 1 motor

I think of this as Type 1 because it’s the simplest and it’s the first kind we saw regularly. (Admittedly, part of why we saw them regularly was they broke regularly). It might actually be the type 12 for all I really know. This is the type of motor usually (but not always) identified simply as ‘a linear electromagnetic focusing motor’ in the product blurbs. The example below is from a Sony 55mm f/1.8 lens but this general type is found in a number of other lenses (I’ve put a table of what type of AF motor is in which lens at the end of the article).

Looking at the focusing assembly from above, you see that the focusing element is set into a plastic tray. The tray is attached to an electromagnet that slides up and down on a permanent magnet (blue line) and two metal posts (red lines) to keep it from wandering around too loosely.

Lensrentals.com, 2016

Lensrentals.com, 2016

If we take the focusing element and motor out of the barrel and look at it from the side, how it works may become more apparent.

Lensrentals.com, 2016

Lensrentals.com, 2016

The permanent magnet is the smaller part that the blue line points to. There are two other pieces of metal that make up this very simple motor: the U-shaped piece at the bottom of this image and the flatter metal plate on the top. They are held together by the force of the permanent magnet, which is really pretty impressive. It’s nearly impossible to pull the two pieces apart using our fingers, we have to insert a small object to pry them apart. There is also a position sensor (green line) fixed to the focusing element. The red line points to a well-lubricated plastic groove that slides up and down over the metal bar you saw in the picture above. That’s it. Very simple.

The copper electromagnetic coil slides up and down on the flat metal plate of the permanent magnet when current is applied. Since the copper coil is attached to the plastic plate encasing the focusing element, it moves the focus element. I want to emphasize the part about ‘the copper coil is attached to the plastic encasing the focusing element’. The method of attachment varies, and it’s important.

In this particular lens, the electromagnetic coil is simply glued to the plastic of the focusing element at one end (red line points to the bit of glue which has obviously failed here). If the glue fails then the coil separates from the lens element. If that happens the coil slides up and down quite happily when current is applied, but the focusing element just sits in one place. Since the coil isn’t attached to anything, it rattles around loosely when you try to autofocus. This is the dreaded ‘buzzing autofocus death’ that can happen with LEMs.

 

Lensrentals.com, 2015

Lensrentals.com, 2015

The Type 1 motor with flat-glue-only is found, as far as I’ve seen, only on the Sony FE 55mm f/1.8 and FE 24-70mm f/4 lenses. These are the two lenses we find have frequent AF motor failures; we’ve reglued dozens of them. Why did they choose to rely on only flat surface glue? My only thought is because someone made a stupid mistake in design; they believed the glue would hold as well as the glue manufacturer said it would. I suspect we won’t be seeing any more Type 1 motors going forward, but then I also expected we’d see a change in the existing lenses using it because it should be a simple change. But that hasn’t happened yet, at least not that I’ve seen.

Type 1a Motor

There is a slightly different type of single LEM system found in Sony lenses. I call it 1a, because it’s better than 1, although it was around before the Type 1. The FE 16-35 f/4 lens  and even the FE 16-70mm lens have are type 1a, as are several others. Below is a picture of the Sony FE 16-35 lens autofocus motor. From above it looks identical to the Type 1.

Sony 16-35 f/4 focusing motor

Sony 16-35 f/4 focusing motor, Lensrentals.com, 2016

 

But these types of motors have one critical difference that isn’t obvious just looking at them at first glance.

Sony 16-70mm focus coil in place. Lensrentals.com, 2016

Sony 16-70mm focus coil in place. Lensrentals.com, 2016

 

If you pry the coil off of its mount (and we had to pry one up because we just never see the kind of AF failures with these lenses we do in the previous type) you can see this very simple difference. Instead of just a flat plate at the bottom of the electromagnet coil, there’s a back that goes up inside the coil, two pieces that go along either side and a couple of sculpted areas in the base, all of which hold glue. It makes a much stronger bond, obviously, and explains why we don’t have to repair these lenses AF systems. So that’s my definition of Type 1a: a Type 1 motor with some reasonable mechanism to hold the electromagnet to the focusing plate.

Lensrentals.com, 2016

Lensrentals.com, 2016

Other Brands Type 1a Motors

The Zeiss Batis lenses also use an LEM for focusing. We expected it to look very similar to the Sony AF motor and it does. Here’s the Zeiss from above.

Lensrentals.com, 2016

Lensrentals.com, 2016

 

It’s actually more than similar. It’s almost identical. Same 2 sliding posts in the same position. Same magnetic motor and electrical coil. There is one difference: the Zeiss lens encases the electromagnet entirely in a plastic box attached to the mount, rather than just gluing it onto the mount. We actually opened the plastic box up and saw that it is fairly filled with glue and there are also plastic clips inside holding it in place.

batisclip

Lensrentals.com, 2016

 

These differences are in the plastic mount holding the focusing element. The permanent and electromagnets, the metal housing of the motor, two sliding rods and everything else about the electric motors are identical. But that’s not too surprising, Sony and Zeiss collaborate on lenses.

Fuji also has LEM motors in a number of their lenses. They are very similar construction to the Sony with slightly different plates, but we’ll show that in the Dual LEM section since Fuji, as far as we can tell, generally uses at least dual motors. Fuji lenses, as far as we’ve seen, also always attach to the electromagnet with more than surface glue, so they all would meet my Type 1a classification.

Dual LEM Motors

Two companies, Fuji, and Sony have released Dual Linear EM focusing lenses. Not surprisingly, these have two motors moving the focusing element. Below is a look at the Fuji 55-200mm motor. You can see the two EM housings and there are still two metal sliding posts. The metal housing the permanent magnet is slightly different in the Fuji: instead of one flat and one U-shaped piece, there are two flat pieces going up-and-down and two I-shaped pieces, one on each end, making a box. You are looking down on the I-shaped top piece in this picture, and can see the top tabs from the two vertical pieces.

Lensrentals.com, 2016

Fuji 55-200mm focusing assembly. Lensrentals.com, 2016

 

Here’s an angled view showing more of the vertical piece.

Fuji 55-200mm. Lensrentals.com, 2016

Fuji 55-200mm focusing assembly. Lensrentals.com, 2016

 

For comparison, here is Sony’s dual LEM from the FE 70-200mm f/4 lens. It has the same metallic parts as the Sony single LEMs we saw above, although in this lens the plastic completely encases the electromagnetic coil, much like the Zeiss Batis lens did.

Sony 70-200mm f/4 Dual LEM, Lensrentals.com, 2016

Sony 70-200mm f/4 Dual LEM, Lensrentals.com, 2016

 

You can see an obvious difference in the spacing of the motors; Sony has theirs 90 degrees apart while Fuji’s are more like 150 degrees. I don’t know if one spacing method is superior to the other but it seems the focusing motor might have less play with the 150-degree spacing. But that’s just me guessing. It may make no difference at all. I should add that all Dual Motor LEMs we’ve seen have some plastic fastening mechanism like a type 1a in addition to just glue.

3 and 4 LEM Focusing Systems

Only Fuji, so far, has gone past two motors, and that only in a couple of lenses. The Fuji 50-140mm lens has three LEMs, for example.

Fuji 50-140mm lens focusing assembly. Lensrentals.com, 2016

Fuji 50-140mm lens focusing assembly. Lensrentals.com, 2016

 

While the Fuji 90mm Macro has four.

Fuji 90mm macro focusing assembly. Lensrentals.com, 2016

Fuji 90mm macro focusing assembly. Lensrentals.com, 2016

 

Why more motors? There must be a good reason because three or four motors has to be more expensive than one or two. I assume the most likely reason would be more power to move a larger element. If my understanding is correct, LEM motors are fast and silent, but not as powerful as a DC motor. There could be other reasons, and I’ll speculate a bit later.

What Did We Learn Today?

Well, you got to see some Linear Electromagnetic focusing systems. We saw that the working parts are very similar no matter the brand. If you’re interested in speculating about that do a patent search and draw your own conclusions about who is making what for whom. I get in enough trouble without doing that here.

We also saw that it seems the simple things, like connecting the electromagnetic coil to the focusing element, can cause problems. Other than that issue, the only problems we’ve seen are a couple of lenses that were dropped and stopped focusing because one of the metal rods had jumped out of place. Except for the Type 1 systems we’ve seen nothing to suggest these motors are less reliable than more common ones.

There’s a lot more to learn about theses systems, but this was the first step. Until we know exactly what system is in what lens we can’t test to see how they are different. Just so I’m clear, I don’t have a bunch of tests lined up. I’m just saying there was no sense even thinking about testing until we saw what was inside. (At the end of the article I’ve added a table of what is inside different lenses, as far as we know. You’ll see that we have a few more to look into before this database is complete.)

What Did We Speculate Today?

Given that the manufacturer’s claims that are supported by outside facts, we know that LEM systems are fast and silent. (By fast, I mean move the element fast, not necessarily lock onto focus fast, although that might also be true.) Some manufacturer’s claim that they focus more accurately than other types of lenses, but I’ve found no outside data to support that, and ‘accurate focus’ is a very vague term. When the marketers say things like ‘more accurate’ my first thought is ‘than what’?

One other thing that isn’t mentioned very much, but is absolutely true, because it’s already happening: LEMs give lens designers some freedom they haven’t had before. The focusing elements can be put inside a zooming group. More than one element in the lens can move for focusing or compensation (this can be done to some degree with helicoid AF systems, too, but it could be easier and more flexible with LEM motors). This is already being sort of done in a couple of Sony lenses. The FE PZ 28-135 lens, for example, uses a ring Piezo motor to move the zoom group in the front of the lens.

Lensrentals.com, 2016

Lensrentals.com, 2016

 

While a dual linear EM system moves the focusing group in the back. In the upcoming 70-200 f/2.8 G Master lens, there will be a similar set up moving two focusing groups.

Lensrentals.com, 2016

Lensrentals.com, 2016

 

If someone wanted to, they could make elements move in opposite directions during focusing, or have a second element move as a focusing or zoom compensator, or whatever. I expect we’ll see some innovative things. Some of those innovative things will be better. Some will just be innovative.

The rest of this is just my thinking out loud. Whether any of this is accurate or simply my ingrained paranoia and random dreaming, only time will tell.

  1. It appears, at least for right now, that single LEMs are most suitable for small, light, focusing elements that don’t have to move very far. Bigger elements probably need multiple motors. LEMs may use less electrical power than USM motors, but I don’t know if this would be significant enough to extend battery life.
  2. The focusing group in single-motor systems seems awfully loose to me. I’m sure it’s better when power is applied. I’d like to think that lens designers took this into account and therefore this doesn’t increase sample variation. But some single LEM lenses are also some of the most variable lenses we’ve tested, so I’m at least suspicious. I’ve also considered that multiple LEM systems are used partially because they result in less looseness of the focusing group. The only fact I have to support this (other than the multiple focusing motor assemblies aren’t as loose) is that the Sony 70-200 f/4 (two motors) is less variable than the 24-70 f/4 and 55 f/1.8 (single motors) so consider this purely speculation on my part. I’ll repeat again, this is with the power off. Things are probably much tighter with the power on. This may just be another example of Roger’s paranoia.
  3. In theory, if good strong glue and a reasonable clamping system is used, one would think the electromagnetic motor should last a long time, perhaps longer than ring USM motors do. On the other hand, the lubricated sliding assembly may get loose or sticky over time. I have no idea. Time will tell, but time takes time.
  4. This is really speculative, but multiple LEM systems (I’d say three motors minimum) might actually be electronically adjustable. The firmware could actually tilt or perhaps even center the focusing element by altering current to one or more lenses. I’m pretty certain this is NOT being done now, but I wonder if it’s at least theoretically possible.

It will be interesting to see how this all works out.

For the near-term, we have several other lenses we want to dissect and look at their LEM motors, and we also need to examine some linear-piezo motors more closely. For now, here’s a table showing some of the more common linear focusing lenses, what the manufacturer says about their drives, and if we have actually looked inside, what type of drive we’ve seen.

Lens Manufacturer's Desc. Lensrentals Description
Sony FE 24-70 f2.8 GMDirect Drive SSM (piezoelectronic)
Sony FE 70-200 f/2.8 GM OSSFront ring drive, rear dual linear EM
Sony FE 85mm f/1.4 GMRing Drive linearPiezo Ring Drive
Sony FE 24-240mm f3.5-6.3 OSSlinearDual Linear EM
Sony FE 24-70 f/4linearType 1
Sony FE 28mm f/2? Linear
Sony FE 35mm f/2.8Stepper motor
Sony FE 55mm f/1.8Linear EMType 1
Sony FE 35mm f/1.4 ZADirect Drive SSMlinear piezoelectric
Sony FE 90mm f/2.8 Macro G OSSDirect Drive SSMlinear piezoelectric
Sony FE PZ 28-135 f/4 G OSS?Stepper?Dual Linear EM
Sony FE 70-200 f/4 G OSSdual linear EMDual Linear EM
Sony FE 16-35 f/4 ZA OSSlinearType 1a
Sony SEL 16-70linearType 1a
Fujinon XF 55-200 f/2.5-5.8 R LM OISDual linear EMDual Linear EM
Fujinon 10-24 f/4 R OISstepper motor
Fuinon XF16-55 f/2.8 R LMDual linear EMDual Linear EM
Fujinon XF18-55 f/2.8-4 R LM OISlinearDual Linear EM
Fujinon 18-135 f/3.5-5.6 LM OIS WRlinear
Fujinon XF50-140 f/2.8 R LM OIS WRTRIPLE LINEARTriple Linear EM
Fujinon XF100-400 f/4.5-5.6 R LM OIS WRDual linear EM
Fujinon XF90 f/2 R LM WRQuad LinearQuad Linear EM
Sigma 19mm f/2.8 DNLinear
Sigma 30mm f/2.8 DNLinear
Zeiss BatisLinear EMType 1a

 

Roger Cicala, Aaron Closz, and Erick Marquez

Lensrentals.com

May, 2016

Country Of Youth – Making A Documentary in Ethiopia With A Mirrorless Camera

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There are times when the smallest decision can make a large impact. I do believe that we have the opportunity to change a life by simply making one small decision. When I’m given the chance to help through photography, I feel it’s my duty to pay it forward.

Recently, I partnered with Nadus Films for their “Give A Story” grant project. We offer grants to international organizations in need of having their stories told. We’ve locked arms with the NFL, ESPN, and many other groups and foundations desiring to see good stories told. Simply put, there’s a lot of great people doing incredible work but they’re inadequate when telling their story or they just don’t tell it at all. We have created a platform to help change that. The grant provides the opportunity to document, capture and provide the right tools, so non-profit initiatives can raise awareness and gain traction for further funding. Our project in Ethiopia focused on a foundation titled “Youth Impact” which provides shelter, food and a clear road for homeless children located in the city of Addis Ababa.

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Nearly 60% of Ethiopia, Africa is under the age of 18 and of that demographic nearly 100,000 children are completely homeless and suffer from injustice in epic proportions. Due to famine, war and civil unrest, some children, just 8 years of age roam the streets of the city. There is an extreme lack of leadership, parents and grandparents. It is a nation of youth. Before I even stepped off the plane, I knew it would be an experience, but I was unaware of the impact it would actually have.

 

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Although Ethiopia is well-traveled by tourism, it’s also a country that is weary of exploitation. Just days before our date of departure, we hit a speed bump and had to re-think our strategy for both entering the country and the equipment we would haul. Our usual gear list consists of cameras, lenses, tripods, grip equipment, lighting, stands, sliders, and stabilizers. We had to break it down to something with a smaller footprint and less conspicuous. We had to play the tourist and travel completely under the radar, which isn’t easy for a professional production crew. Luckily, thanks to the efficiency of LensRentals, we were able to grab the right lightweight and mobile tools for the job on top of a stripped down version of our normal equipment list.

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Against all our intuition, we decided to leave the production cameras at home and risk it all with two mobile mirrorless systems. Despite being such a small camera, we knew the Sony a7RII could still pack a punch. With the help of an Atomos Ninja Assassin, the camera will record in ProRes, an uncompressed version of 4K. They are lightweight, have fantastic low-light capabilities and a solid dynamic range. The Sony Alpha systems have always exceeded my expectations.

At the last minute, we added a product to the list that would alter the production; we rented a DJI Ronin-M 3-Axis Brushless Gimbal Stabilizer. We had never taken a stabilizer such as this to any production in a foreign country. But, we settled on the fact that it could add an element of value to the cause. It would be a risk to add a piece of equipment to the baggage, but it was a risk we felt would cash-in and push the end product to new heights.

With little experience in this equipment, we spent hours in orientation to guarantee we knew the system in and out before landing on the ground in Ethiopia. After days of packing and working through the new gear, we had a solid game plan and only one equipment kit per person. We could only cross our fingers to avoid any questions and snags during our entry into the country. The flight was long and the checkpoints were stressful, but we landed safely on the ground with only a couple of standard hiccups.

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Unlike the first time I visited Africa for The Waterboys initiative in 2015, Ethiopia surprised me. It is much more advanced as a country than Tanzania; however, it is much more damaged—while Tanzania fights for water, Ethiopia yearns for security. The people of Ethiopia are proud of their culture, religion and heritage but I could sense the desire for more; a longing for a better life. That being said, the people of Ethiopia are weary of the unknown. Even though our project and purpose was indirectly saving their lives, they are hesitant to any type of image—any recreation of reality, including documentary work. Understandably, we encountered much resistance in our project due to the fear of being exploited. With such a high risk of conflict, we had to be unobtrusive and low profile, regularly in the shadows.

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Photographing this project in Addis Ababa was one of the most difficult assignments I’ve had. Much of the content I deliver is street photography and a production-style touch of photojournalism. Although, it’s not what I do nor what I’m known for, it’s something I really enjoy. It takes me outside of my comfort zone into a life behind the lens. It’s my security blanket in these strenuous and precarious locations. Nevertheless, the people of Ethiopia are terrified of the unknown. Despite our project indirectly saving the lives of their own, they are hesitant of any type of picture, including documentary work. Due to the fear of exploitation, we were met with a lot of resistance and “hands over the face.” It made our job so difficult, we had to be quick, inconspicuous and constantly in the shadows.

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As the possible location for the Garden Of Eden, the birthplace of coffee, and a culture so rich and vibrant, it is impossible to deny that Ethiopia has impacted the world. Despite most of our journey taking place in the consolidated slums of Addis Ababa, towards the end of our travels we left the hazy cityscape and ventured out into the marvelous pastures of Ethiopia. Eventually we came upon the Blue Nile Gorge; a historical ground of wildlife, unique plant-life and mile-high canyons. The sharp rock and sepia-toned structures composed a landscape of beauty and awe. I distinctly recall inhaling the fresh air for a short-lived high after the grueling week of documentation.

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At last, we could let the DJI Inspire Drone loose and capture the beauty of the vast and incredible landscape. The first few hours were spent outlining specific shots, which had to be captured at precise times. Our final shot would be the tallest hurdle of the entire production. The Blue Nile Gorge consists of a massive waterfall with has helped sculpt the Portuguese Bridge; a rocky structure that has three main arteries. It was created in the 16th century by the Portuguese to cross the enormous waterfall. Luckily, when we arrived to the canyon, it was during the driest season; however, deep pools were still present that the local youth would jump into from a thirty-foot, jagged cliff. This was our shot, this was our ending. We wanted to capture the thirty-foot jump from multiple perspectives. An overhead drone, a stabilized tracking shot and a static frame from below towards the natural pool. After six jumps and a lot of trial and error, we had the shot in the can. Despite our crew being utterly drained, we celebrated by making the jump ourselves.

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The Sony system performed beautifully. Albeit, the rigging altered depending on the circumstances, we were very confident in the footage we had captured throughout the course of the week. The people of Addis Ababa may move slowly, time moves quickly in this style of production. In some cases we had no option of using the Atomos Ninja Assassin, other times it was called for and we rigged it up. We kept one camera handheld and one camera rigged to the DJI Ronin-M Stabilizer. The two camera partnership allowed for both intimate action as well as high-production-value style shots. Every night we settled into the dailies with a massive breath of footage.

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We pushed the Sony a7RII to its video limits and it shined. The system didn’t necessarily convince the crew to move to a more mobile cinema camera, but we now know it’s a system that can be used when the situation calls for it.

This experience transformed me—I now drink coffee and obsess over Ethiopian spices. But the trip changed and impacted me on a deeper level also, I returned to the United States with a new found respect for those involved in such selfless acts, like helping others or raising a community. I am often asked about Ethiopia and I’m instantly reminded of the faces of children who had never seen themselves in a photograph; never had their story told. My only hope is that our documentaries and my photography can shape the lives of people for the better all over the world.

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Clay Cook

Guest Contributor

Is the New RED Weapon, the Weapon of Choice?

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The choice is simple; are you cool, or are you boring? That has to be the big decision RED wants you to make, right? Sure, the argument could be made that you choose RED for the stunning 6K resolution that it offers, or the 16.5 plus glorious stops of dynamic range, but really you want it because there’s a skull on it, and you are a video pirate. Cool right? Worth upgrading your Epic right?

RED-Weapon-Punisher

The truth is, RED’s Weapon camera offers very little in technical improvements over the RED Epic Dragon. The sensor in the Weapon is the exact same 6K RED Dragon sensor, which means, the same resolution options, the same dynamic range and the same signal to noise ratio. Another way to put it is that the Weapon offers the exact same recording options and same frame rates at the same resolutions. The primary difference technically is the integrated Mini-Mag media bay, which offers faster data rates when using the Mini-Mags over those allowed by the Epic Dragon. Currently, the only advantages are lower available compression ratios at all record options. Presumably these higher data rates will also assist with future feature set upgrades, whether it be through new sensor technology, or firmware.

REDWeapon-Verse-RED-Dragon

Another improvement, over the Epic Dragon build, is that RED has reduced the weight of the camera by almost two pounds. By using a combination of aluminum, and magnesium alloys, they have managed to shave off the pounds, without compromising the rugged build quality of their product. This improvement vastly helps gimbal and drone operators with their delicate balancing act of keeping a rigs weight within spec, but also allows for fewer compromises with lens and accessory choices, when weight limits become a factor.

Additionally, one nice feature added to the Weapon is the ability to record in Apple ProRes (and a near future DNxHD option has been promised). This codec option offers productions greater ability to fit footage shot on RED into a variety of workflows that may not call for RAW recording. Moreover, simultaneous RD3 and ProRes acquisition, allow for seamless proxy workflow. Built in 3D LUT support and wi-fi control further round out the new built-in feature set on this camera.

An added feature built into Weapon is simplified swapping of the camera’s optical low pass filter. The new OLPFs can be removed and installed with the simple turn of a torx key, however, it should be noted, the “fast-swap” still requires powering down the camera, removing the lens mount, and exposing the sensor to dirt and debris. RED currently offers 3 flavors of their OLPF (standard, low light optimized, and skin tone), fined tuned for different shooting situations.

OLPFSwapGIF

The ability to customize and expand your RED to fit a variety of shooting scenarios has been at the heart of the RED camera design since introducing the first Digital Stills and Motion Camera (DSMC) build. RED trademarked the phrase “Obsolescence Obsolete”, which trumpets the expandability and upgradability of the RED camera line. With the expansion into Weapon , RED sort-of holds up this statement. Some accessories carry over directly such as all of the available lens mounts, which adapt directly to the Weapon using the same four torx screws. Those who have Mini-mags will also get to carry them through to Weapon, however, by integrating the SSD module directly to the brain, RED has made adoption of Mini-Mag SSDs mandatory moving forward. Other accessories can be brought over to the Weapon via available adapters. These include DSMC LCD Touch units and cabled battery plates. Unfortunately, for some accessories, such as the DSMC Side Handle and the Switchblade, the Weapon is a rocky place where they can find no purchase.

New DSMC2 accessories have been designed to integrate directly with the Weapon brain. These include cable-less LCD Touch units and battery plates which aim to streamline the RED and presumably cut down on weight and umbilicals to optimize use in a variety of shooting scenarios. For a breakdown of compatibility, you can take a look at this PDF.

Overall, Weapon is a minor technical advance for RED. Weapon’s use of the Dragon 6K sensor mean image quality and resolution are identical to that of the Epic Dragon. Still, the truth is, if you are a RED owner, you’ll eventually need to bite the bullet and upgrade your camera, so you can take advantages of newer technology when it becomes available. Fortunately, the camera’s expanded functionality, including features like ProRes codecs and built in LUT support, should offer enough incentive to justify adoption of the new system.

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The big question remains; Can these upgrades help the camera find a new audience? Obviously, there are some major adherents to RED cameras and what they can do, but do you need it for your shoot? I feel that the camera is too much for most shoots. RED’s previous cameras require a certain kind of “check the gate” discipline and multiple member camera departments, found on motion picture sets. My experience with Weapon leads me to believe the same. Smaller shoots, requiring “run-n-gun” style shooting are still better served by cameras like the Canon C300 Mark II and Sony FS7, which are feature rich, and were designed with single shooter operation in mind.

If you still want to shoot on RED, I suggest you strongly consider renting the RED Epic Dragon over the RED Weapon. Unless you know you need the lower compression ratios for your project, you want to try before you buy, or you want to make sure your camera rig fits within a specific weight limit, there is really no compelling argument to be made right now for choosing RED Weapon.

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