a blog by Matthew Duclos
Duclos Lenses has spent a few years designing and refining their very own Autocollimator Bench for measuring and adjusting back focus of precision cinema optics. Here’s a bit from their press release. Continue reading “The New Duclos Autocollimator Bench”
Here at Duclos Lenses we’ve devised this somewhat satirical guide for buying new cinema lens. Take a gander and see what lens you come up with. Post your results in the comments and five winners will be chosen at random at the end of the week to receive some cool lens geek swag including shirts, hats, cleaning kits, etc.
This guide is all in good fun, but if you really do want some professional advice, contact Duclos Lenses.
Click here or on the image below for a full res version. Enjoy!
Arri has provided a really simple, comprehensive diagram of the three different iris rod standards. It seems like there has been a lot of confusion about the proper distance from the axis of the lens to the center of the rods. A few basic details to go through here: The height of the rods (the distance from the lens axis to the center of the rods) is critical as a standard when designing accessories such as matte boxes, follow focuses, low bridges, or just about any lens related accessory. In this post, I’ll discuss the relationship between the different iris rods (15mm LWS, 15mm, and 19mm) and their associated low bridges.
15mm LightweightThe smallest and newest system to be utilized for motion picture work and as of recent, possibly the most common. The 15mm Lightweight system (LWS) is a variation of the 15mm Studio setup with roots began in ENG and DV setups. With the introduction of the DSLR revolution and tiny camera rigs such as the Blackmagic Pocket Camera and in some cases even a simple GoPro, the 15mm Lightweight system has carved it’s own place into the motion picture world commonly found on medium sized rigs such as RED and Sony cameras. The 15mm LWS is aligned to the center of the lens mount, with a relatively narrow spacing (60mm) and a fairly shallow axis to rod height (85mm).
If there was an “old school” rod setup, 15mm Studio would be it. 15mm Studio rods are the same rods as 15mm LWS but spaced farther apart (100mm), farther from the lens axis (118mm), and slightly offset from the optical center (17.25mm). Don’t get me wrong, 15mm Studio is probably the most common among high-end cinema sets based on the West Coast despite it’s age. The 15mm Studio system has become somewhat overlooked in terms of standardization with all the newcomers to the motion picture camera accessory manufacturing game assuming that the rods were aligned to the optical center. As far as I know, the reason for the offset of 15mm Studio rods was originally to compensate for weight and accessory distribution. The camera had additional weight on the “smart” side due to the viewfinder and controls so accessories such as the follow focus or motors were attached to the “dumb” side to balance out the setup. I’ll admit, the 15mm Studio standard is far older than me or anyone reading this and I’m no motion picture historian… If your 15mm Studio rods aren’t offset, then they’re not 15mm Studio.
If you’re anywhere other than Hollywood, you’ll likely find 19mm rods used as the standard. 19mm Studio is the updated version of 15mm Studio. As lenses and lens accessories became heavier and heavier, the need for stronger rods came about paving the way for a slightly heavier duty system. The 19mm Studio setup is spaced even farther apart than 15mm Studio (104mm), and slightly more distant from the optical axis (120mm) but is centered on the lens. The purpose of the 19mm system was to increase the load capacity when used with heavy lenses and reduce flexing.
Traditionally, stainless steel is king. These days you’ll find dozens of different companies producing “rods” from aluminum and carbon fiber which is fine for more 15mm LWS rigs where weight is critical and the stress put on the rods is minimal. Aluminum and carbon fiber may even be suitable for some 15mm Studio setups if they’re not demanding, but if you’re rig requires the wider offset of 15mm Studio rods, then you’re probably not worrying about the overall weight of your camera rig and should opt for a stainless steel variant. The same can be said for 19mm Studio – if you’re going to go with the beefier 19mm setup, don’t cheap out and use flimsy aluminum or carbon fiber. If you’re on the fence between 15mm Studio and 19mm Studio, there’s always 15mm HD rods. No, not High Definition… Heavy Duty. This would be a 15mm rod with a wall thickness double that of the normal 15mm rods. This provides a much more solid support with little to no flex even with a hefty Angenieux or Fujinon zoom. Iris rods will come in all sorts of lengths these days depending on their application. A heavyweight cinema zoom will call for 24″ rods whereas a DSLR rig may only require a few inches simply to attach a follow focus to the front of the rig or a battery to the back.
A simple pair of carbon fiber rods. Carbon fiber rods are usually hollow with end caps to keep dirt and dust out, but can also be found in a sturdier solid carbon fiber material.
The confusion comes in mostly when companies design and sell products that don’t conform to an industry standard. For example, a simple google search for a 15mm matte box will yield results from around the world with little to no mention of what system a given matte box is actually designed for. I’ve seen matte boxes advertised with 15mm rod holes but 19mm Studio spacing or 15mm LWS spacing but with 15mm Studio height. Some with fully adjustable offset and height, others with absolutely no height adjustment. I guess you just have to hope your camera plate has a height adjustment… Matte boxes are the primary source of confusion with the other most common accessory, the follow focus and/or motors not being much of a concern. This is because most follow focus systems will have a slide or pivot adjustment to accommodate different size lenses minimizing the standardization to simply rod size and spacing, disregarding offset and height.
Arri MB-20 II Matte box sample: Note the top pair of 15mm holes (15mm LWS) is centered on the optical center whereas the lower pair (15mm Studio) is clearly offset from the center. Also note the height difference.
Additionally, the height has been a topic of confusion in the recent past. Lets use the Red 300mm prime for example. Originally it came with a built in support, a bright red ring towards the front of the lens with a simple 1/4-20 (I think) threaded hole. If I remember correctly, there wasn’t any standardized height. You either had to use an arbitrarily adjustable, standard-less low bridge or stack bunch of washers just to attach the lens securely. It wasn’t designed for 15mm LWS or 15mm Studio. It was just a big red block with a hole in the bottom. It’s possible that Red intended the 300mm to be used with the 15mm LWS standard, but since when is a 300mm, one foot long, 6 lb. prime lens considered lightweight?!?!
While we’re on the topic of height; the other critical spec, the same chaos experienced with matte boxes can also be found in low bridges. The low bridge is the key to lens support. A lens can have a support post with standardized height and a nice 3/8-16 thread but it’s useless without a proper low bridge. A proper low bridge will be somewhat forgiving in terms of standardization with minor adjustments for height and offset, but not so much that the industry standards can be completely overlooked. With the 15mm Studio and 19mm Studio standard, a proper low bridge is easy to come by. Because of all the confusion with proper heights and standards when 15mm LWS was adopted for motion picture rigs, you’ll find that there are many 15mm LWS low bridges with a fully adjustable height. This makes them pretty useful but sometimes sloppy depending on the brand.
A proper 15mm Studio low bridge with adjustable height and offset.
I hope this clears up some of the confusion surrounding iris rods and lens accessories. Anytime someone asks me what brands I recommend for a matte box, follow focus, or low bridge, I generally stick to a single rule which is stick with the established brands. A company that has been manufacturing motion picture accessories for a good decade or so will know what they’re doing and will obey the standards making life easier for all of us. Of course, there’s an exception to every rule and in this case, it’s usually budget. If you can’t afford a high quality accessory, make due with what you can, but you’ll probably end up getting the higher quality product in the end so you might as well start with proper gear.
Several months back, Canon held an event at their Hollywood HQ showcasing their complete line of Cinema Eos products, but focused on (pun intended) their cinema lenses. There were a couple of speakers; one ,who’s name escapes me at the time of writing this, coming from a new-age cinematographers point of view talking about the benefits of modern image sensor technology and compact, lightweight style shooting – and the other, Larry Thorpe. If you’re not familiar with Larry Thorpe, he’s basically a guru of all things image acquisition. He’s worked for RCA, Sony, and now Canon. One may jump to the conclusion that he loves Canon lenses so much simply because it’s his job being a marketing exec. at Canon… But Larry is truly passionate about his work and optics in particular and it shows.
Larry’s presentation at the Canon event revolved mainly around optics and discussed current and future technologies. Canon released a PDF which essentially mirrors Larry’s presentation at the event that I’ve linked here. Give it a read and see why Canon is making waves in the industry with their cinema optics. See the PDF below.
So you bought a new Sony F5 or even better, an F55. Or you’re upgrading from a 5D to a C100 or C300. You’re Red Epic needs some better glass for the upcoming Dragon sensor. Regardless, congrats. Now you need some lenses to get the best performance out of your new camera. But where do you start? I don’t know if you’ve noticed, but there’s a new camera almost every month these days. Sensor tech continues to improve and grow. However, lenses are a lifetime investment. Unless you jumped on the 2/3″ train and bought some lenses that are useless now you may have also noticed that a set of, now vintage, classic Zeiss Super Speeds is still $50k and they’re almost 40 years old!!! Let’s explore some options that won’t break the bank and still give you some amazing performance. Continue reading “2013 Cine Prime Lens Buyers Guide”
Having trouble keeping track of all the new cinema zoom lenses offered by manufacturers such as Angenieux, Canon, Arri, and Fuji? Fear not my friends. Here is a quick reference chart showing most of the common zoom lenses used by professionals around the world. Feel free to download and share.
Work in progress, please feel free to leave feedback. 🙂
I’ve touched on Zeiss’ success over the past decade, all based on their old Zeiss ZF and ZE line of lenses. The ZF lenses started to become extremely popular with the VDSLR revolution and low point of entry into the world of motion picture acquisition. The ZF lenses were updated and replaced with the ZF.2 line which made using them on modern Nikon cameras easier and more feature rich. Zeiss proceeded to take those same internals and implant them into bigger better housings in the form of Compact Primes, their first new cinema lens in quite a while. The compact primes were good but they had a few problems. The speed from one lens to another was inconsistent and the mounts were fixed. Zeiss addressed both of these issues by limiting the entire range to T2.1 with the exception of the already slower 18mm, 21, and 25mm and introducing their interchangeable mount system. This pleased most users that wanted a versatile set with consistent aperture throughout the set. But where did those faster primes go? Continue reading “Do Your Speeds Need to be Super?”
This post is part of a series of upcoming reviews of camera-lens mounts and their pros and cons. Quite possibly the most common camera-lens mount on the market today is the Canon EF and EF-S mount. Introduced in 1987 and updated in 2003, the EF-S mount added several features that improved on the original FD Mount including focus motors placed inside the lens to enable auto-focus. Step forward 2.5 decades and the Canon EF and EF-S mount are the reigning champion of still photography and quickly gaining popularity in the world of cinema. For the sake of simplicity, I’ll simply refer to the Canon mount as EF instead of EF or EF-S. If you need more clarification on the difference between EF and EF-S, google it. 😉
In a recent post I declared that it’s better to invest in glass than in cameras since new cameras come out every few months. I wasn’t just saying that to get people to buy glass, I meant it. Just this year there have been at least half a dozen cameras released or announced, if not more. With more cameras there comes more choices for lenses. Wether it’s a BlackMagic camera with it’s mighty little crop sensor or the new 5DMk14B-R whatevermagig. Lenses will always be required for cinema and in todays economy it’s all about compromise. So where do you compromise and what lenses make the most sense for you? Continue reading “More Lens Options Than Ever”
Everyone knows that bigger is better. Kinda… Larger sensors are often associated with lower noise levels and generally higher quality photos while smaller sensors are associated with lower data loads and higher transfer rates but noisier and generally lower quality images. It’s a trade off at this point in technology. What a lot of folks need to remember is that there is a fundamental difference between sensor size and sensor resolution. In particular when it comes to Red cameras and their wonky formats. A lot of people including Red staff will describe lens coverage in regards to a specific resolution such as “4K” or “5K”. That’s great since they pretty much own the names and if someone is asking if a lens covers 4K, they’re usually referring to a Red One or 5K on an Epic. But that’s where things get confusing.
For the Canon CN-E Primes PL Conversion, click here.
The PL mount is an excellent standard that Arri gave us several decades ago and has been the industry standard alternative to Panavision’s camera mount ever since. The PL (Positive Locking) mount is large enough to accommodate sizable rear elements and strong enough to support the largest of professional cinema lenses (with proper support of course). More and more cinema is moving over to Nikon F, Canon EF, and even the Micro 4/3 standard. So why is everyone trying to slam a PL mount on their grandfathers old set of Nikon AIS lenses? It’s simple. All three of the still photo mounts I mentioned have their limitations that can really disrupt a cinematographers flow. For example, Nikon, Canon, and M34 all have a locking pin that keeps the lens set in it’s place and you push the little button to release the pin. Most of those camera mounts have a very weak leaf spring that keeps a bit of pressure on the lens mount to stabilize the lens. Certainly not as much pressure as PL mount fully tightened. Still photo mounts usually have one position that the lens attaches to the camera in and that’s it. you can’t rotate the lens relative to the camera whereas PL mount, depending on the lens manufacturer, can have up to four mounting positions, each 90 degrees apart. Not a deal breaker but still just another reason PL is superior for cinema. I can go on all day about the benefits of PL mount over Canon or Nikon mounts but that wouldn’t help many people. Continue reading “Canon EF to PL, Is It Possible?”
The DSLR Revolution is in full swing at the moment and everyone is scrambling to get the glass they love on the camera they are stuck with. It doesn’t sound too difficult to simply change a piece of metal, but there are a lot of things to consider when attempting to change a mount. After-all, lenses are a precision tool, naturally. Lens and camera manufacturers all have their own mount system which specifies a flange depth, the distance from the mount flange to the film/sensor plane. When this number is accurate, the image that the lens produces falls on the sensor in perfect focus. Move it forward or backward by the smallest amount (.0005″) and your collimation will be completely off, throwing out your focus marks and destroying the accuracy of a lens, especially a zoom lens. All of the different SLR camera manufacturers had a similar theory and design, but just slightly different numbers for the flange depth. Wouldn’t it be great if they all agreed on a standardized mount that would allow any lens to be used on any camera? Yeah, it would be great. But that’s not how it works.
Zeiss released their CP.2 (Compact Primes) cinema lenses about a year ago, not long after they dropped their original Compact Primes on the market. There has been a lot of debate about the value of the Compact Primes. With an influx of new primes with a range of price tags, there is no shortage of choices for the budding cinematographer or even the veteran looking to invest in some glass. At $3,900 a piece, or a set of five lenses just shy of $20k, the Compact Primes are some of the cheapest options out there for what I would consider professional cinema lenses. However, a lot of cinematographers are opting for the ultra budget conscious still photo lenses with Cine-Mods to bring them up to cinema spec. But what makes the Compact Primes so much more expensive than, say, a Zeiss ZF.2? After all, they are in fact the exact same glass but in a different housing, right? Sort of… There are quite a few features that really separate the two lenses no matter how similar their heritage is. The ZF.2s are Zeiss’ latest all manual still photo lenses. They just happen to make very pretty images when mounted to a motion picture camera as well as a still photo camera. The Compact Primes take it a step beyond pretty images and provide a professional set of features that can be very valuable to a cinematographer and his/her crew. I’ll start with the optics. Zeiss says that the CP.2 lenses use hand-picked elements that really increase the consistency and accuracy of the lenses. I can’t attest to this as I haven’t seen any difference in the glass or the test results produced by the Compact Primes, but it looks good on a brochure.
A lot of people have asked about cleaning lenses and dust in the optics. I’ve considered doing a few short videos on glass cleaning techniques and tips but never really went through with it. It’s difficult to explain, it’s a skill that comes with years of practice. It’s like asking a surgeon how to perform surgery… He can explain and even demonstrate, but that doesn’t mean you should attempt it yourself. Thus, I always say the best way to clean your lenses is to not let them get dirty. I do a lot of work with still photo lenses these days with the whole DSLR revolution and all and every now and then I get a request to clean some dust, dirt, or debris from inside an otherwise pristine Canon or Nikon lens or similar. I almost always have to turn people down simply because the cost of labor compared to the cost of the lens is prohibitive. Your average Canon Eos lens costs a few hundred bucks. The average time to disassemble a lens enough to access debris inside the optics, clean in out (properly), re-lubricate, reassemble, align and collimate optics, is about 4-6 hours if not more. This amount of time in service can equal or exceed the value of the lens, in which case it’s usually better just to buy a new lens. Some people like to think that the “Pro” lenses with their weather sealing are immune to dust and contamination but that’s simply not true. They are better at keeping contamination out, but not perfect. Some of the higher end L glass would be worth a good cleaning if it’s a specific lens you are partial to. The cost:value ratio prohibition doesn’t usually apply with cinema lenses. Even professional cinema lenses get dust in them on a regular basis, but these lenses are designed to be serviced and cleaned. If you shoot in a clean studio environment and keep your lenses in well sealed cases when they aren’t in use, you probably won’t see much dust in them over their life. If you’re a run-and-gun shooter, swapping lenses constantly in the desert, you’re going to have problems with dust and debris sooner or later. I have a client that shoots motocross events for a living with his Epic camera and a couple of Angenieux zooms. His lenses get destroyed on a regular basis, coming back from jobs covered in dust, dirt, mud, everything that doesn’t belong in a lens. The lenses are worth quite a bit which makes cleaning them worthwhile for him. We clean them up, calibrate them, and send them back into the field to shoot again. Continue reading “Keeping Your Lenses Clean”
Round Two