by Allan Tépper
Picking the best cameras for a TriCaster-based live TV studio starts with a key question: Do you want/need a virtual set or a traditional, organic one? The answer to that question will set you on two very different paths since the camera priorities change drastically depending upon whether or not you want to use virtual or traditional, organic sets. Unlike other virtual sets from some other manufacturers, NewTek’s virtual sets allow for realistic zooming into your studio action while simultaneously zooming the simulated background at an equal pace and distance.
Above is a freeze frame of a TriCaster virtual set shot with one of several cameras covered in this article.
This means that for a virtual set, you need cameras with pristine optics, sensor, and DSP (Digital Signal Processor) without the need for active zooming in the camera, since the active zooming takes place digitally in the TriCaster. In the case of a virtual set, your cameras don’t even absolutely need a zoom lens, although it can be helpful just to compose the closest shot without having to move the camera or carefully pick a particular prime lens for a camera that accepts interchangeable lenses. On the other hand, if you don’t want or need virtual sets, you might consider conventional HD cameras or even the synergy, cost-effectiveness, and repeatability of NewTek macros combined with robotic cameras with their own zoom lenses.
This article will also prepare you to understand other factors (like progressive versus interlaced video and the ideal framerate for your productions), which are also important factors in choosing the ideal cameras for your studio.
Sections in this article
- Robotic cameras versus conventional cameras
- How to control robotic cameras directly from your TriCaster and save money by not purchasing PTZ controllers
- Everything you ever wanted to know about genlock but were afraid to ask
- Connections between your cameras and your TriCaster
- CCU: Camera Control Unit
- Tally lights
- Resolutions: spatial versus temporal
- What you should know about progressive versus interlaced video
- How to choose the ideal framerate for your programs
- How to interpret, adjust, and match the menu settings in your cameras with that of your NewTek TriCaster
- Examples of cameras
Robotic Cameras vs. Conventional Cameras
Robotic cameras are also called PTZ, which is an acronym for Pan/Tilt/Zoom. With almost any type of production, the use of robotic cameras gives us many advantages:
- You save the cost of a tripod and intercom headsets to speak with camera operators.
- Your ex-camera operators are now free to do other tasks.
- You can pre-design and pre-program complex movements as TriCaster macros for certain sections of your productions which will be totally repeatable with absolute precision and reliability, which is impossible with human camera operators. Camera movements can also be combined —frame accurately— with onscreen graphic moves, and even with pre-recorded sound via TriCaster macros. This is ideal for the opening, close, or bumpers.
- All current professional TriCasters and the new TriCaster Mini models (i.e, all models except for the TriCaster 40) offer direct control of robotic cameras, which can also save you the cost of independent controllers, simplify your devices, and optimize the automatization.
On the other hand, if you want the power and flexibility of a virtual set or NewTek’s special Holographic LiveSets, you probably don’t need robotic cameras or even camera operators, other than to position and compose the cameras initially. The rest of the apparent camera movement can come from the virtual set or Holographic LiveSets in the TriCaster. As covered in more detail ahead, not having to perform zoom or other other movements during a shot also opens the option of using prime (non-zoom) lenses, or lenses whose zoom lens does not maintain focus or aperture (iris) during a zoom, as in the case of most affordable photographic lenses used with HDSLR or mirrorless cameras.
How to Control Robotic Cameras Directly from your TriCaster and Save Money by not Purchasing PTZ Controllers
Generally speaking, the control of robotic cameras (PTZ) is done through serial RS232, RS422, or RS485… or via network connections. As indicated earlier, all professional TriCaster models and the new TriCaster Mini models (i.e. all but the model 40) are capable of both. However, we must keep in mind that TriCasters don’t have any serial port, so if your robotic cameras require RS232, RS422, or RS485, you’ll need an inexpensive USB to serial converter for each one.
Everything You Ever Wanted to Know About Genlock But Were Afraid to Ask
The TriCaster 8000 and TriCaster 460 are capable of genlock. The TriCaster 40, TriCaster Mini models, and TriCaster 410 do not include any genlock input. Genlock is a compound word that comes from the sub-words generator and lock. It is not obligatory to use genlock with any TriCaster since all NewTek TriCaster models feature frame synchronizers for each physical input. However, if both your cameras and TriCaster have genlock, it behooves you to use it, by sending a sync signal (usually black burst) to all of the cameras and the TriCaster. In that case, you must acquire a sync generator (or black burst generator) of your preference separately. By default, TriCaster accepts a bi-level SD (standard definition) sync signal (i.e. black burst) even for HD installations. In addition, TriCaster models with genlock are also compatible with tri-level if you have it. In that case, there is a TriCaster setting to switch from bi-level to tri-level. If you send a genlock signal to the TriCaster, it will then offer you phase adjustments in case you want to use your TriCaster as a source to feed a traditional video mixer you may have owned previously.
There are several advantages to using genlock with your TriCaster and cameras when possible. With genlock, there will be less delay and less signal processing. Also, there won’t be any need for the frame synchronizer to throw away an occasional frame.
Digital audio is less tolerant than analog. Some other systems (from other manufacturers) absolutely require genlock in order to mix digital audio with digital video. To alleviate that, TriCaster features an audio resampling circuit for each input. Nonetheless, it’s recommended to use genlock if available. However, if your TriCaster or cameras don’t accept genlock, no worries. That’s why there is a frame synchronizer on every input. If you own —or are leaning towards— purchasing one of the TriCaster models that don’t have genlock, then there is no reason for you to have that feature in mind when selecting cameras.
Connections Between Your Cameras and Your TriCaster
Excluding network video inputs, the available types and number of physical video inputs vary among current TriCaster models. The TriCaster 40 accepts analog video signals only via its physical camera inputs. The TriCaster Mini (HDMI) accepts digital video signals only, via its HDMI inputs. The TriCaster Mini (SDI) and the TriCaster 410 accept digital video signals only, via their SDI inputs. The TriCaster 460 and TriCaster 8000 accept either analog or digital video, and their digital video inputs are SDI. All TriCasters with digital video inputs, whether HDMI or SDI, can optionally accept embedded digital audio via those inputs.
If you have a TriCaster 40, the only physical video inputs are analog, and there are three types, in order of highest quality: component (aka YUV or Y, R-Y, B-Y), Y/C (S-Video) and composite. If you choose to have analog-only camera sources to connect to a TriCaster 460 or TriCaster 8000, the same options apply in the same quality priority.
Both HDMI and SDI are capable of sending pristine digital HD video from your HD camera to your TriCaster. Some current HD cameras have only one connection or the other while some have both. If you already own a TriCaster with SDI inputs, and your cameras also offer SDI, then that is the best connection. If you own a TriCaster with SDI inputs but would like to connect very inexpensive cameras to them, that is still possible using converter boxes that go from HDMI to SDI for about US$300 each.
On the other hand, if you have an HDMI version of the TriCaster Mini, you can easily connect cameras with HDMI output, at least if they are within the range of NewTek’s 100-foot (30.48 meters) bundle of four cables for US$495 (which works out to cost US$123.75 each, just for reference purposes). But you can also connect SDI cameras to the HDMI version of the TriCaster Mini using converter boxes, which cost about US$300 each.
If you plan to use full CCUs (camera control units) which are covered in more detail in the next section, then the connection between the cameras and the CCU could be multicore or fiber optic. That will be irrelevant for the TriCaster since a modern CCU will have either HDMI or SDI output.
CCU: Camera Control Unit
CCU is an acronym that stands for camera control unit. Traditionally, many TV studios have used a full CCU not only to control many aspects of each camera remotely but in some cases to convert the signal.
Example of a full CCU from Sony
Full camera control units typically connect to the camera via multicore or fiber optic cables, and then have a more standard output to connect to the video mixer (“switcher”). Nowadays, those connections would likely be SDI or HDMI.
The CCU makes it much easier to set the ideal exposure, white balance, and other settings to optimize and match the cameras from your seat at the TriCaster. Although TriCaster, fortunately, features proc amps (a short name for processor amplifiers) to tweak each camera source, the best quality and signal-to-noise ratio is achieved by optimizing the signal first at the camera and then finally doing fine tweaks in the TriCaster’s proc amp.
Example of a mini CCU from Sony
Beyond the full CCU (which actually receives the signal from the camera and delivers it on its output), there is another type of CCU called a mini CCU which controls the camera remotely but does not receive or deliver the camera’s signal.
Mini CCU from Datavideo to control up to four Sony supported cameras. Datavideo also offers similar models for JVC and Panasonic cameras.
Both full and mini CCUs are valuable tools, but neither one of them is absolutely necessary.
Some cameras are specifically made for studio use and come from the factory with intercom connections. Other cameras have an optional “studio configuration” or studio accessories. However, if you decide to use human camera operators, you don’t have to purchase a camera designed with this feature, since there are third-party intercom systems that can be used with any camera, or even with no camera at all, in the case of a floor manager in a studio.
This Datavideo ITC-100 Intercom Base Station & 4-User Headset/Beltpack Kit which costs about US$1100 and can be expanded.
Tally lights are special indicators that visually show which camera is “on air” at any given moment, both for the talent in front of the camera as well as to the camera operator (if there is one) to the rear.
Tally Lights LLC is a company from Michigan that manufacturers tally lights and adapters made specifically for different TriCaster models.
Resolutions: Spatial vs. Temporal
There is much confusion about the word resolution, what it means and how it is measured. Some people erroneously believe that the only way to measure resolution is in quantity of pixels. First, I’ll explain the huge difference between spatial resolution versus temporal resolution. Then, I’ll clarify something even more fundamental: the difference between resolution and sharpness.
Spatial resolution is indeed measured in quantity of pixels. Some examples of television resolutions include:
- 1920×1080, also known as HD 1080p (progressive)
- 1920×540, a way of expressing HD 1080i, although some people express it as 1920x1080i (more details in the next section)
- 1280×720, also known as HD 720p
- 720×486, an SD (standard definition) resolution
- 720×480, another SD resolution
- 640×480, another SD resolution
The adjective temporal within the term temporal resolution is related to the word time. Followers of the TV series Star Trek, The Next Generation will recall the frequent use of the term temporal in that sense. In the video and television worlds, temporal resolution usually refers to the frame rate per second, although sometimes in the case of interlaced video, it refers to the field rate per second. (More about that in the next section.)
The reason it’s called temporal resolution is because the more frames per second (i.e. the higher the frequency), the more information is captured… and the more fluid the movement is perceived. Of course, that difference of perception of movement is much more noticeable when the content is dynamic, and much less noticeable when it’s static (as with a talking heads TV show) as we’ll cover later in this article. Some examples of different types of standard temporal resolution are listed here:
- 23.976 progressive frames per second, also known as 23.976p or 23.98p, is apt for Blu-ray, DVD, over the air TV, and the web. Some TV stations, unfortunately, demand that it be handled with a pulldown over 59.94. There will be more details about this ahead in this article. (At publication time of this document, NewTek indeed supports the 23.976p framerate, but rounds it to “24” in TriCaster menus.)
- Exact 24.000 progressive frames per second, also known as 24p is typically used with cinema and DCP, not for over the air TV or DVD. In some cases, the 24.000 framerate can be used for Blu-ray and for the web, but it’s less frequent. (NewTek currently doesn’t support 24.000 as an output format… and it’s not necessary for conventional TV or for the web. For those cases, we have 23.976, which is visually identical.)
- 25.000 progressive frames per second, also known as 25p, is apt for over the air TV in PAL or ex-PAL areas, Blu-ray, DVD, and web. In some cases, it must be converted into PsF. More information is ahead in this article. (25p only comes included with international NewTek models.)
- 29.97 progressive frames per second, also known as 29.97p, is apt for over the air TV in NTSC or ex-NTSC areas, Blu-ray, DVD, and web. In some cases, it is necessary to convert it into PsF. More information is ahead in this article. (At publication time of this article, NewTek indeed supports the 29.97p framerate, but rounds it to “30” in TriCaster menus.)
- 50 fields per second, also known as 25i or 50i, is another way to express 25 interlaced frames per second. (50i only comes included with international NewTek models.)
- 50 progressive frames per second, also known as 50p (for final delivery, is generally limited to TV stations with a spatial resolution of 720p in PAL or ex-PAL areas, save for a few exceptions, which we’ll cover in detail ahead in this article. (50p only comes with international NewTek models.)
- 59.94 fields per second, also known as 29.97i or 59.94i, is another way to express 29.97 interlaced frames per second. More information is ahead in this article. (At publication time of this article, NewTek indeed supports 59.94i, but rounds it to “60” in TriCaster menus.)
- 59.94 progressive frames per second, also known as 59.94p, is for final delivery, but generally limited to TV stations with a spatial resolution of 720p in NTSC or ex-NTSC areas, save for a few exceptions, which we’ll cover in detail ahead in this article. (At publication time of this article, NewTek indeed supports 59.94p, but rounds it to “60” in TriCaster menus.)
“Full HD”: A Disparaging, Inappropriate, and Misleading Term
The term “Full HD” obviously means “complete HD”, which is confusing, inappropriate, and damaging for the video production community when used as a haughty nickname for 1920 x 1080p, since it attempts to insinuate that 1080p is always superior to 720p, and that any other HD (like 720p) is “incomplete HD”. The reality is that when creating the current high definition (HD) over the air systems, both 720 and 1080 were included in order to emphasize each one’s unique virtues, taking into account the general shortage of bandwidth. The 1080 system favors spatial resolution while the 720p system favors temporal resolution. That’s why many sports channels —which have plenty of movement in their content— have favored the 720p system while those channels that mainly broadcast movies, whose temporal resolution has traditionally been 24 frames per second (but are often conformed to either 23.976 or 25 according to the region) have preferred 1080. Completely apart from favoring one type of resolution over the other, there’s another important reason why many news channels chose 720p over 1080: In many cases, by using 720p, they can continue to use their original microwave transmission systems, without having to purchase new ones for HD.
As I indicated in a recent article in ProVideo Coalition magazine, there are currently at least 41 TV networks in the United States that chose —and continue to use— the 720p system. They probably did it for one of the mentioned reasons. Those individuals who erroneously believed that the 720p system was “older” or “inferior” no longer have any excuse. Each system has its respective virtues and weaknesses.
Resolution vs. Perceived Sharpness
The final perceived sharpness encompasses many factors that go beyond spatial or temporal resolution. Other often forgotten factors include the optical quality of the lens and the contrast range, to which both the lighting and the digital signal processor (DSP) of a modern camera contribute.
What You Should Know About Progressive vs. Interlaced Video
In the era of SD (standard definition) television production, everything (or almost everything) was (or is) interlaced video. Rather than using complete frames, each frame was divided into two fields, each with half of the total resolution. One of two fields encompassed the even lines and the other handled the odd ones. Later, the interlaced SD TV set or monitor would do its best effort to recombine the fields back into a frame. According to the system and format used, some would put one of the fields first (i.e. the field containing the even lines) and the other after, and others did the reverse. The need to combine footage from one dominant field with other material that used the opposite was (or still is for some) challenging. Another negative point of the interlaced system is that it often exaggerates digital compression artifacts.
On the other hand, progressive video handles complete frames, without splitting them into separate fields. So, progressive video doesn’t have the challenge of field dominance, nor does it exaggerate digital compression artifacts. Progressive video also facilitates extracting a freeze frame with full resolution. Some individuals erroneously associate progressive video exclusively with low framerates, like 23.976, 24 and 25. However, as we saw in the prior section, there are also high framerates for final progressive delivery (50p and 59.94p).
Why did television engineers bother to invent interlaced video when it’s so obvious that progressive video is superior? Because it’s a way to fake having more resolution (both types) when there is a shortage of bandwidth, which is exactly what they had when creating standard definition television systems many decades ago.
Modern projectors, monitors, and TV sets are practically all natively progressive, although many can accept interlaced signals. It is also vital to understand that anything that is broadcast to the public via the web must be progressive. So if your original material is interlaced, at some point, some device or process is going to convert it into progressive. Some of them do it better than others… and some do it quite poorly.
It’s also essential to realize that 1080HD TV stations (including those that erroneously insist on receiving all material in 1080i and that they absolutely “can’t receive anything that’s 1080p”) indeed can do so in nearly all cases, although sometimes (due to misunderstandings) it’s necessary to deliver material to them in a disguised interlaced format. If your original material is 25p, you can convert it into 25PsF, which appears to be 50i (sometimes called 25i) but it will, fortunately, preserve the original 25p visual look. Likewise, if your original material is 29.97p, you can convert it into 29.97PsF, which will appear to be 59.94i (sometimes called 29.97i), but it will preserve the original 29.97p visual look. PsF is an acronym for Progressive Segmented Frame. With PsF, the original frame’s resolution is segmented in half. One-half of the original resolution goes to each artificial field. So what’s the difference between PsF versus authentic interlaced video? Authentic interlaced video contains different temporal information in each field while PsF has the identical temporal information in each artificial field. Due to the Blu-ray specs, it’s necessary to convert some frame rates (25p and 29.97p) to PsF (25PsF and 29.97PsF respectively) when encoding. Fortunately, Blu-ray authoring programs like Adobe Encore do that automatically when they detect that the original is 25p or 29.97p. However, the last version of Adobe’s Creative Suite to include Encore is CS6. Adobe chose not to include Encore with the CC version. Other authoring programs probably do the same thing, automatically creating PsF from those two framerates. If not, we should do it manually to assure compatibility with all Blu-ray players, since although some Blu-ray players can play native non-standard 1080/25p and/or native non-standard 1080/29.97p, that doesn’t mean that all will.
For those 1080HD TV stations that, unfortunately, refuse to accept native 1080p material, if your original is 23.976p, you must convert it to 23.976p-over-59.94i via a 2:3 pulldown (also known as 3:2) to satisfy that situation. That process is also called telecine.
We’ll see this in more detail in the section called ahead in this article since that’s the way many cameras output a progressive signal.
How to Choose the Ideal Framerate For Your Programs
If you produce for a 1080HD channel; if your program has less movement (i.e. talking heads), then you have the option to produce programming in 1080p (even though for live streaming, you may reduce it to a lower spatial resolution although you can leave it at 1080p for on-demand playback):
- 1080/23.976p (At publication time of this article, TriCaster menus show it as “24”.)
- 1080/25p (Only available with NewTek international models.)
- 1080/29.97p (At publication time of this article, TriCaster menus show it as “30”.)
If you live in a PAL or ex-PAL country, 25p will be an excellent option for you. If you live in an NTSC or ex-NTSC country, you could save on bandwidth (or have less compression per frame with the same bandwidth) by using 23.976p. That’s what I would do in an NTSC or ex-NTSC area if it were mainly a “talking head” show, with very little movement. Also, all of these framerates are compatible with all important web services and with all recent mobile phones and tablets. The important detail from the last sentence is framerates. For some tablets or phones that aren’t so recent and whose screen resolution is lower than 1920 x 1080, it will be necessary to “scale” or reduce the number of pixels, which is done automatically with many online video services including YouTube and Vimeo. Fortunately, as opposed to temporal resolution, spatial resolution (pixel count) is very scalable without affecting the visual look. It just fits perfectly on different screen sizes with different spatial resolutions.
If you produce programs for an over-the-air sports TV channel, it’s very likely that the channel has chosen to work with 720p, since as we clarified earlier, that system favors temporal resolution due to the fast movement, with a mild sacrifice in spatial resolution. So if you’re producing material for a PAL or ex-PAL sports TV station, you’ll be best served by producing 720/50p, which can also be expressed as 720p50. On the other hand, if you’re producing material for an NTSC or ex-NTSC sports station, you’ll be best served by producing 720/59.94p, which can also be expressed as 720p59.94. However, if you plan to webcast your signal, either live or on demand, —or if you plan to distribute it some other way so it reaches mobile devices (i.e. tablets and phones)— you should keep in mind that up until now, there are great limitations of high frame rates (50p or 59.94p) to those destinations. It’s true that YouTube and YouTube Live are (to my knowledge) the first to offer 59.94p for the web (Livestream and Vimeo still limit us to 29.97p maximum, if you send 50p or 59.94p to Livestream or Vimeo, they’ll drop every other frame), there’s another problem that is probably even more critical: The majority of tablets and phones have the same limitations of 30 frames per second. Even the brand new iPhone 6s and iPhone 6s Plus limit playback on the internal screen to under 30 frames per second. If you create material at 50p or 59.94p, those devices will end up playing half: 25p or 29.97p. Your viewers that see it on those devices that are limited to 30 fps will see something quite different from what they’ll see on TV sets or computers… or on very recent tablets and phones. They won’t only see half of the framerate: The vital relationship between frame rate and shutter speed will be lost, and hence it will have an inconsistent look. So for sports, we have to decide what’s most important: maximum fluidity on TV sets (50p or 59.94p) or visual consistency across all devices, large and small, at 29.97p or 25p.
If you have heard of “720/60p” or “720p60”, it’s very likely that the original source of the information was rounding it up from 59.94 to 60, either intentionally or innocently. In fact, at publication time of this article, that’s the case even in the menus in NewTek TriCaster products. So you now know that NewTek, some camera manufacturers, and even some TV channels often round the number for simplicity or space sake. Integer numbers like 30.000 and 60.000 really haven’t been a television standard since the United States colorized the monochrome system back in 1953. However, some innocent engineers and even camera manufacturers have fallen into the trap of taking those rounded numbers literally (for example, the Canon 5D MKII camera, before a firmware update, supplied exactly 30.000 frames per second, which caused lots of problems, since it was non-standard.) Fortunately, NewTek has built its equipment in such a way that they can correct the issue via the frame synchronizer which is available on each source input. (When using a “60” session, the NewTek output will always be proper 59.94, despite the rounding in the menus.) However, it’s always better to get the desired framerate directly from the camera whenever possible, as we’ll see in more detail in the next section.
Obviously, your desired framerate is something you should keep in mind when picking cameras since not all cameras offer all framerates.
How to Interpret, Adjust, and Match the Menu Settings in your Cameras With That of Your NewTek TriCaster
If you have decided to work with 720p
If after reading this article up until this point, you have analyzed the advantages and disadvantages, and you have decided to work with 720/50p or 720/59.94p, fortunately, most cameras that offer a 720p mode can deliver a pure and legitimate signal. So with those 720p installations, it’s rather obvious how to interpret, adjust, and match the camera menu settings with those of the TriCaster. The situation is often quite different for those who have decided to work with 1080p. That’s the purpose of the rest of this section.
If you decide to work with 1080p (progressive)
If you have read this document up until here, you have learned the advantages and even the need to deliver a progressive signal for the web and modern screens. Although fortunately most recent 1080HD cameras offer progressive modes, it’s sad that many of the most popular ones don’t output a pure progressive signal via their HD-SDI or HDMI output. Many of these cameras output signals like 29.97p as 29.97PsF (which is disguised as 59.94i), 25p as 25PsF (which is disguised as 50i) or –in a much more complex way, 23.976p-over—59.94i (called telecine).
The few cameras that output pure progressive 1080p
If you are lucky to have one of the few 1080p cameras that can output a pure progressive signal at its native frame rate via its HD-SDI or HDMI, that is absolutely the best way to set it for your TriCaster since it will require minimum processing (and delay). The few HD cameras I have seen that do this are those from Blackmagic Studio (with latest firmware), Datavideo, Nikon, Panasonic GH4 (with latest firmware), RED and the very new Sony model A7s (US version), which can output pure 23.976p via HDMI, although the A7s menu says “24”, as does the TriCaster menu. After you set the camera to operate in the desired framerate, set it to output natively over HDMI or SDI, and then set the TriCaster’s input for the same. For example, if you decided to set the camera to 1080/23.976p (which in some cases is rounded to “23.98” or “24”), set the TriCaster input to “1080/24p”. If you set the camera to 1080/25p, set the TriCaster input to 1080/25p. If you set the camera to 1080/29.97p, set the TriCaster input to “1080/30p”
IMPORTANT NOTE about the TriCaster Mini:
At least with the initial version of the TriCaster Mini with HDMI inputs, there is no manual control about how to treat each camera, since the TriCaster Mini is designed to detect the camera’s temporal resolution sent by the camera via EDID automatically. However, if NewTek discovers that some camera sends erroneous information via EDID when receiving a PsF or telecine signal, the company has committed to adding manual correction via an update. If that happens, the way to set it will be as described below.
HD 1080p Cameras That Output Disguised Signals
Most professional and consumer HD 1080p cameras that I have tested (beyond the exceptions I just mentioned) output a progressive but disguised signal. If you really want 29.97p, the best type of signal those cameras can output is 29.9PsF (although the camera menu might call it “30p”). If you wanted 25p, the best those cameras can output is 25PsF (although the camera menu might call it something different). If you wanted 23.976p, the best signal those cameras can output is 23.976p-over-59.94i (although the camera menu might call it something different). So in those cases, set the TriCaster’s camera input to “1080/24 telecine”, 1080/25PsF or “1080/30PsF” respectively.
Explanation About the Relatively Rare 1080PsF23.976
Although there are many HD cameras that output 25PsF and 29.97PsF as indicated above, there are very few low-priced camera models that output 23.976PsF, which actually appears to be 47.952 fps. A few examples include the Panasonic AF100 and the extremely popular Sony PMW-EX1R & PMW-EX3 with latest firmware. That rare 23.976PsF signal is not currently supported by any TriCaster and it’s unlikely that this will change, and that is fine, since there are always other ways to handle that framerate, either natively (the preferred way, when possible) or by reversing telecine of the 23.976-over-59.94 signal, as explained above. All current TriCaster models are capable of both of these two methods.
Stay Away from Auto-Detection to Avoid Unnecessary De-Interlacing
If your camera does not output a native progressive signal, it is best to set the camera inputs of the TriCaster manually, when available. Otherwise, there is a very high likelihood that the TriCaster will be deceived into believing that they are interlaced signals and de-interlace them unnecessarily. It is much better to have the TriCaster reverse pulldown the 2:2 or 2:3 (aka 3:2) signal than to have it de-interlace a signal that is already progressive.
Here are some camera examples.
Traditional 1080p HD Video Camcorder
For a traditional HD video camera used with a TriCaster and a virtual set, I tested the Sony PXW-X70.
I previously knew and liked this camera for several reasons:
- It has a great picture.
- It has both HDMI and SDI output for maximum flexibility.
- When used as a standalone camcorder, it can record internally at 4:2:2 10 bit at 50 megabits per second using the professional XAVC Long GOP códec.
- With a street price under US$2000 including its built-in motorized zoom lens, the PXW-X70 is also a WorldCam, meaning that the same camera can do all desired worldwide framerates, including 23.976p, 25p, 29.976p and 59.94p (although the non-integer framerates mentioned are rounded in menus with the current firmware). Here is the test I did with the PXW-X70:
I did this test thanks to Rodolfo Matamoros (owner of the PXW-X70 camera) and Midtown Video of Miami, Florida, US, owner of the lights, studio, and greenscreen. I intentionally brought a tweed jacket for Alex of Midtown Video to wear, to test how well the cameras would avoid showing moiré. The camera was set to shoot at 1080/29.97p (“30p” in the camera menu) and it output 29.97PsF (called “interlaced” in the camera’s menu, but we know it is really 29.97PsF). The TriCaster input was set to “1080/30PsF” and reversed the 2:2 pulldown on the fly. If you were to use the camera in a more active set, this camera has a built-in zoom whose aperture (iris) and focus follows throughout the range. If you want to connect a wired remote zoom via LANC, you’ll just need an inexpensive adapter from the PXW-X70’s multi A/V port to LANC, or one of Sony’s own remotes that connect directly to the multi A/V port.
Robotic 1080p Camera
I also tested an example of a robotic camera, the PTC-150 from DataVideo.
The PTC-150 is also worldcam, offering 25p, 29.97p, 50p and 59.94p. (The PTC-150 doesn’t currently offer 23.976p or 24p.) For the test, PTC-150 was also set to 1080/29.97p, although in the menu it is called “30p”. I confirmed that in this mode, the PTC-150 actually outputs pure progressive 29.97p. I used a Shogun from Átomos to verify that. The TriCaster input was set to “1080/30p” so no reverse pulldown was required for this source. Just as in the first example video, the zoom took place in the TriCaster, not in the camera. The PTC-150 also has both HDMI and SDI outputs and costs under US$3000 including its built-in motorized zoom and pan/tilt/zoom which can be controlled by any current TriCaster except the TriCaster 40. There are similar 1080p robotic cameras available from Sony in a similar price class.
Low-Cost, High Quality 1080p Mirrorless Camera That Accepts Interchangeable Lenses
If you want an affordable HD camera with interchangeable lenses, I would consider the Panasonic Lumix GH4 together with a Speed Booster.
The Speed Booster from Metabones effectively makes the camera act as if it had a much larger sensor, since it reduces the crop factor and increases the effective sensitivity. Since firmware 2.1, the GH4 is capable of outputting native 23.976p, 25p or 29.97p (and more) over its Micro HDMI output (the best ways to connect to your TriCaster), although there have been further firmware updates since then with other improvements. As the publication date of this article, the GH4’s current firmware version is 2.4. The Speed Booster is available either for Canon EF lenses, Nikon F mount, and some others. Keep in mind that most affordable zoom lenses designed for photographic cameras of any brand won’t maintain zoom or aperture (iris) during a zoom, since most of those lenses were designed for still photography. As a result, those zoom lenses should be used only to pre-compose, not to zoom while shooting or broadcasting video. Of course, they are fine for use with a fixed camera with a virtual set, where the TriCaster does the zooming within a shot, as described earlier. Although I have not yet had the opportunity able to test the GH4 with a TriCaster, I am quite confident that the combination will work very well as indicated as long as the firmware is updated and the camera is set to output the native framerate of 23.976p, 25p or 29.97p. Like the Sony PXW-X70 in its category of cameras, the GH4 with a Speed Booster produces amazingly good images. If used with a TriCaster Mini (HDMI version), you’ll need either a cable long enough to go between them, or a cable adapter that goes from Micro HDMI to female standard HDMI to connect to the HDMI cable set from NewTek. If used with any TriCaster that accepts SDI, you should use a short cable from Micro HDMI to male HDMI and then a converter to SDI. I also like the fact that the GH4 shows non-integer framerates like 29.97 properly in its menus.
Here is a review to help you to pick your studio cameras:
- First, decide whether you want or need virtual sets/Holographic LiveSets… or if you prefer an organic one. If you want to use the former, then your cameras will be static once positioned and pre-composed. If you decide to use a traditional organic set (or if you are creating a mobile unit), then you should decide whether to choose robotic cameras or an HD camcorder that occasionally can be taken out of the studio to shoot EFP (electronic field production).
- Depending on your content type (the two extremes being talking heads or fast-moving sports) and primary & secondary distribution channel (720HD over the air/cable, 1080HD over the air/cable, or Internet including mobile devices), determine whether you’ll prioritize spatial resolution (pixel count) or temporal resolution (framerate). Then you can pick your framerate, remembering that spatial resolution is easily scalable, while temporal resolution is not.
- Choose your camera candidates taking into account the aforementioned decisions.
- Look at reviews (mine and from others) online and (when available) with local demonstrations.
- Follow the instructions in this article to set the proper framerate and output signal, and set the TriCaster according to those instructions.
About the Author
Born in Connecticut, United States, Allan Tépper is a bilingual consultant, multi-title author, tech journalist, translator, and language activist who has been working with professional audio and video since the early eighties. Since 1994, Tépper has been consulting both end-users and manufacturers through his Florida company. Via TecnoTur, Tépper has been giving video tech seminars in several South Florida’s universities and training centers, and in a half-dozen Latin American countries, in their native language. Tépper has been a frequent radio/TV guest on several South Florida, Guatemalan, and Venezuelan radio and TV stations, and he currently conducts the CapicúaFM radio program. As a certified ATA (American Translators Association) translator, Tépper has translated and localized dozens of advertisements, catalogs, software, and technical manuals for the Spanish and Latin American markets. He has also written contracted white papers for manufacturers. Over the past 18 years, Tépper’s articles have been published or quoted in more than a dozen magazines, newspapers, and electronic media in Latin America. Since 2008, Allan Tépper’s articles have been published frequently —in English— in ProVideo Coalition magazine. More info at AllanTépper.com
NewTek sponsored this article after receiving Allan Tépper’s proposal. As of the publishing date of this article, Allan Tépper has no commercial connection with Átomos, Blackmagic, DataVideo, Panasonic, JVC, Metabones, Sony or Tally Lights LLC other than that some of them have sent him review units or have contracted him to do consulting, technical writing or translations in the past. The words and opinions of Allan Tépper expressed herein are his own.
More Articles by Allan Tépper
- Make Your Corporate Webcast Look Like Network TV With LiveText
- How To Design Your Audio Setup for TriCaster Mini, Part I
- How To Design Your Audio Setup for TriCaster Mini, Part II
- How To Design Your Audio Setup for TriCaster Mini, Part III
Read our related article: 4 Things to Consider When Choosing a Portable Camera