Camera accesories. How are we going to dress our new camera?.
Is it reasonable to make the choice of a camera conditional upon its accessories? Are they really that convenient or necessary? Are we acquainted with every feature in all elements available on the market? And how to use them to get the most?
Text: Luis Pavía
We will endeavor to answer all these questions and some others. First of all, we would like to establish some premises. The first one is to clarify that our main purpose is explaining the usefulness of most of the accessories currently available, something that is not always as clear as it seems at first glance. In addition, we will do the complicated exercise of trying to minimize the mentions made to brands or models, so as not to build a commercial catalog; also, this content can serve as a reference in the future while maintaining its validity over time. And finally, we have grouped the different elements into functional blocks. Let’s get to it!
It is very common to find situations in which a lot of attention is paid when choosing a camera for a project or to turn it into our main tool, and very little to its versatility or ability to adapt to changing circumstances. Sensor size, resolution, and dynamic range are usually the main and unchanging parameters, but we will discover other details that can make a big difference in the future.
Is it because our cameras are not good enough? Of course they are! So why do we need the accessories? Because they are precisely what allows us to enhance their capabilities and, even on some occasions, we should take them into account when choosing our model. The reason is that minor features may or may not enable adding devices that expand their capabilities far beyond what we would have initially imagined, or occasionally need, such as -for instance- RAW output or several takes with different signals for different monitors in parallel.
This enhancement possibility makes special sense in cases in which we only occasionally need to cater to certain needs for certain clients. By renting the right equipment for these specific situations, we can deal with them without having to invest in elements that we may never use again.
In such cases, client profile and satisfaction will be key to many of our decisions. It is not about convincing them of the success of ours, but about knowing when a client is able to distinguish and assess the different types of results that are achieved, how much they are willing to pay for this and when their priorities differ.
Due to the length of the topic to be covered, we will split the content into two parts. And, as you know we like to do quite often, we will try to provide content that is far from the typical collection of brands and models, focusing instead on the key features offered by each range so as to identify what we should look for and what they contribute towards achieving what we are aiming for.
In this section we could publish not only a feature article, but a whole encyclopedia, so usmmarizing this topic will be quite a challenge. features such as the mount or bayonet on the one hand, and the adaptation to the size of the sensor on the other, will be the first physical characteristics that obviously constrain their feasibility in our cameras. The need for power supply and software compatibility wwill be part of the specifications that we must also check carefully when making our choice.
As for the mount, each manufacturer usually has its own and, in some cases, also they also build it to meet some standard, like the well-known and firmly established PL mount, from the world of classic cinematography. But even in the same mount from the same manufacturer it is necessary to ensure that the chosen optics are suitable for the required sensor size, that is, checking that the image circle so created perfectly covers the entire sensor area without vignetting. This happens because it is very common to find optics made for small sensors that would be useless in larger sizes.
It does not mean that they are worse quality, although it is true that the greater difficulties and demands when building larger optics can reserve that extra quality found in higher ranges for versions designed for larger sensors. While in those designed for smaller sizes, it will be easier to find clearly cheaper models. Let us also remember that an optic is suitable for any sensor equal to or smaller than its nominal size; note that in such cases we must consider the adequate correction factor to properly interpret its focal length.
Once physical compatibility is assured, it will be critical to be clear about what type of images we intend to create and then decide on the appropriate optics for our visual narrative. That can also change for each project. In general, and any other features being equal, a fixed focal length will offer more brightness, less distortion and better contrast and sharpness than a zoom. And among zooms, the greater the range of focal lengths, the more compromised all its other features will be.
As always, features are never good or bad. They are simply adequate to our needs or not. There are excellent zoom optics that offer a wide range of focal lengths, more often than otherwise they are not the brightest and we will only find them available for small sensor sizes, such as the classic 2/3 inch in broadcast cameras fitted with B4-type mounts.
It is also important to consider electrical compatibility. A good number of current optics can include internal servomotors for controlling all or some of their mechanics: iris, focus and zoom. This is the most common situation when working with optics and camera bodies from the world of photography. It would be very unusual to find compatibility problems in these cases, as long as the camera and optics are from the same manufacturer.
Although what should really concern us in these cases is software compatibility. Software…? Yes, that is correct. Most modern lenses are not just optics and precision mechanics, but in many cases an interface is much more than a simple electrical control of the optics’ servos from the camera body and, in addition, they communicate through sophisticated information exchange protocols. In these cases, we must be extremely cautious, and not only with initial compatibility, but with the consequences of a potential upgrade in firmware (internal control software, something like the operating system of each device).
Finally, let us open a small parenthesis in this section to deal with adapters. These are rings manufactured to facilitate the use of optics from one frame on bodies from a different one. In this case the possibilities are very limited since, due to the build of each frame, combinations that are virtually impossible do exist. There is usually a perceptible loss of luminosity and, in addition, in many cases a part or even all features relating to communication or control between the optics and the body are lost.
There are some of recognized quality and benefits, but in general they entail a more than reasonable compromise solution when the budget -or any other conditions- do not allow access to the optics which we would like to work with and thus ensure that the client will be satisfied with the final result.
Recording media (cards and disks)
We could say that these are the celluloid of the 21st century. They are the physical media in which our recordings will be stored. As always, from the most generic and economical memory cards, such as CompactFlash or the different variants of the SD family, to the most widespread proprietary XQD, SxS or P2 cards, or others even more specific. Each camera or recorder will require its own, and all of them have different ranges that we will have to reckon with and select based on our needs.
The most striking fact is usually capacity which, funny enough, will be limited by the management capacity of our camera. It is not something very common, but as a consequence of the different file systems required for managing certain capacities, there may be the case of cameras that do not recognize the latest generation or large-capacity cards. In these cases, a firmware update for the camera could solve the issue, but let’s make sure that this will not generate undersired side effects or other incompatibilities, as we have just seen that could happen with the optics.
Yet, we believe that the really most relevant specification about a card is not its capacity but transfer rate or speed instead. We must read the specifications carefully. Some feature fairly high rate, but only when reading, and the one that really has an impact for us when recordings is writing speed, since it will have an effect on the maximum quality at which we will be able to work. In this case, we must base our decision on the specifications of the camera or recording device that we are using and, therefore, be acquainted with the different rates required for the qualities we want to work with, and then choose the card that meets or exceeds said specifications.
Exactly the same is true for disks. Nowadays it is unlikely that mechanical hard drives will be used, in view of their sensitivity to movement, the majority of them being solid-state drives like SSD. We will approach the concepts of capacity and transfer rate in the same fashion. Although these parameters will generally be significantly higher than for cards, it will also be a common practice to use them in more demanding situations such as in external recorders.
Very much in line with the previous point, these devices are one of the items that allow us to significantly expand the capabilities of our camera. As a result of their processing speed and the high transfer and recording rates required, most cameras are generally not capable of recording RAW-type formats internally. But they do have a direct data output from the sensor, the signal that can be recorded in these devices. And not only this RAW format, but some others as well, always depending on the needs of each specific project. That is the reason why in our introduction we mentioned the importance of certain features as a decision driver, not for using them right away or permanently, but to count on them should the need arise.
In these cases, there are a few considerations to take into account. Size and portability are the first decision element. Then follows connectivity, which is usually via SDI or HDMI links. From the simplest devices, which come only with one input in one of the formats, to the most sophisticated and complete ones, which feature both types of inputs -bridged to the respective outputs for possible additional cascaded devices- and can even offer the possibility of switching formats between them.
They are powered by one or two batteries or by an external power supply, which allows -or not- long recording sessions. It is a usual occurrence that if you have a connection for two batteries they work in relay mode, thus allowing for permanent powering as long as we have enough batteries charged.
The same goes for the number of slots for cards or disks. If there is only one, our continuous recording capacity will be limited by the capacity of the card or disk, while if two are available, continuous recording for long periods, or even recording in two different formats simultaneously, will be possible.
Last, it is common for them to be equipped with a screen to monitor the signal. Here again, we find big differences. From screens which -due to size, resolution or color precision constraints- only allow for information on the existence of a signal, to those that provide image monitoring by applying LUTs or assessing it with tools such as a histogram, vectorscope and/or waveform monitor.
Typically, they record the audio that arrives synchronously and embedded with the video, and the only thing than needs to be done is simply check that all the channels sent by the camera can be recorded. This requirement is usually fully met since it is very common for them to handle between four and eight audio channels.
Monitors (Video assist)
In this case, specificity is much higher. There is a wide range of possibilities; from small portable monitors to medium or large field monitors, which enable very different uses. But much the same as in the previous case, size, portability and connectivity will be the key elements for choosing.
Unlike in the previous instances, these focus all their functionality on a reliable recreation of the incoming signal; either as a mere presence in which quality is not decisive, or up to the highest precision in sharpness and color. In these cases, and even more so in current times where RAW recording is so widespread, it is important that LUTs can be applied. In this way, and given this format’s unique exposure requirements, a signal similar to the final result that will be achieved after the color grading process can be provided, thus facilitating the evaluation of the signal.
The purpose of this equipment is to get the signal generated from the camera to a more or less distant place, dispensing with any type of wiring. The relevant range can be from a few meters up to the other face of Earth, literally. To achieve this, there are different technologies and possibilities depending on the needs.
Thus, we have autonomous wireless equipment in which the transmitting unit collects the camera’s signal and sends it to the receiver through its own point-to-point link. At the point of reception, the signal is reconstructed as if it were the other end of a cable. In these cases, the technology is usually supported by several channels on free and public frequency bands such as Wi-Fi or radio, splitting the signal between them and then recomposing it by using a technique known as bonding, but without the need of relying on any other additional elements or services.
In these cases, signal quality is usually guaranteed. Range is limited and also decreased depending on barriers such as walls or structures between the transmitter and the receiver. Even latency is an aspect that is quite under control. This delay suffered by the signal from the moment it leaves the camera until it becomes available at the receiver’s output does not usually have an impact on feasibility, but it will be an important aspect to wath out when selecting the ideal equipment for our production.
As an alternative to cover theoretically infinite distances we have other systems, colloquially known as backpacks. These devices rely on data transmission technology through mobile phone providers and use one or more channels to deliver the signal to the receiver. The big difference in this case, lies in the fact that transmission is achieved through the standard public Internet network.
The great advantage here is that range is theoretically unlimited because the receiver will be in a place, such as a production company or a television station, that will foreseeably have plenty of connectivity. Although there are limitations such as the range being restricted to broadcasting from a place with mobile data coverage, quality will be conditional to network availablity and latency can be significant. And this can limit certain possibilities. Take, for example, a remotely controlled camera: a delay of just a few seconds runs the risk of causing inaccurate movements.
These elements also offer a wide range of possibilities. Common in the world of broadcast studios and cinema, optics remotes have seen their use extended to lower-budget productions. The simplest ones are mere mechanical controls that, -by means of a gear- handle the ring to which they engage in a smooth and precise manner. The most common use is for focus, but they are also practical to control the iris or even the zoom. In cinema-type optics the necessary toothing is part of the rings themselves with standardized measurements to mesh with the continuous thread of the relevant remote, while in those not fitted with this, the part having the toothing would have to be attached to the relevant ring.
Naturally, differences in quality of construction and finishing vary between the various ranges of the different manufacturers. With more comprehensive features as we move up the higher end, we find models that include physical stops to facilitate, for example, transfocal operations.
For a more sophisticated action, there are models controlled by a servomotor. Among their main benefits: they allow to memorize various positions, controlling the speed or making it variable with great precision without the need for an expert hand, and even with the possibility of remote control.
This remote operation can be relatively close, with the control unit connected with a cable, or from a large distance when using a radio link connection for communication between the control and the servo systems. These are the most common options, for example for hot heads or cameras fitted in places that are hard to access while filming. Again, the various ranges offer more or less benefits in terms of functions, distance, precision, etc.
Although they will be reviewed in their relevant section, we must mention that all these controls require a rig-type support. This support is normally a pair of cylindrical bars running from the base of the camera to the front of the optics and whose purpose is precisely to provide a mechanical support for this and other types of accessories.
Continuing with the range of models, it is worth mentioning the electromechanical controls that actually operate the servomechanisms fitted on the optics through an electrical connection. Similar to the ones mentioned above, their main feature is that the servo systems are fitted into the optics, and we only need the appropriate electrical connection for operation. These are normally found attached to the tripod handles in broadcast studios for large studio or event optics. Naturally, it is an essential requirement that they be the right model for the optics that we want to control.
Again, we are dealing with an area that would itself provide content for another encyclopedia. Summarizing as much as possible, these are the well-known devices that allow us to capture sound, but all their advantages and possibilities are not always clear.
The first thing that we must take into account is the number of input channels and connector type, being XLR the most common in the professional field and the 3.5 mm mini jack, the typical one in cameras from the photography environment. The reliability, mechanical and electrical robustness, and performance of an XLR is unquestionable. But once plugged in, how is sound picked up?
There are several classes of microphones based on construction, although we will focus on two. In the first place, condenser microphones, usually of higher quality and more sensitive, but more delicate and traditionally vulnerable to humidity. In addition, they require power to function, hence many cameras have a selector to correctly manage their input, both with regards to level and power supply, but only in XLR connections. Secondly, the dynamic microphones, which offer somewhat lower sound quality, but are extremely robust and reliable in practically any environment and situation. Attention, when we mention quality we are referring to microphones that are comparable in all other aspects. Let us not make the mistake of comparing ‘the best’ of one type with ‘the worst’ of the other.
More features to take into account are sensitivity, which indicates the minimum signal at which it will produce a correct recording; response curve, which indicates the range of frequencies to which it responds under optimal conditions; and signal/noise ratio, which indicates the ability to separate clean sound from internal electronic noise.
By physical shape we distinguish three large groups: barrel, the typical one mounted on ENG-type cameras; of hand, usual in scenes and interviews; and tie or lavalier microphones, the tiny ones that are usually attached on clothing near people’s necks.
But beyond physical characteristics, we consider that the most important aspect is directionality, that is, the directions with respect to its axis from which sound is captured with greater or lesser amplitude. The most common ones are: omni-directional, when sound is equally picked up from any direction; bidirectional, when sound is captured from both sides, but very little from the front; directional, when it mostly picks up sound only coming from the front; and cardioid, which picks up from the front and the sides, but whose sensitivity diminishes as we move away from the central axis. As this sensitivity curve is lengthened forward, we find the supercardioid and hypercardioid variants.
Almost all combinations of these specifications can be found on the market, so our sound technician will have to choose based on each particular scenario, purpose and need.
Microphones must always be connected to the camera or recording device chosen for our production. The connection to the camera is always wired and needs its own audio input, since even the wireless models end in a receiver that connects to said input. And in this sense, a caveat which we do not always take into account. In the case of wireless connections, it is a common practice to render a dual conversion: the microphone transmitter makes a digital transmission that the receiver converts into analog in order to connect to the camera’s XLR, which again converts into digital when recording. To avoid this, there is already a wireless receiver model that allows digitally connecting to the camera body without going through the XLR connector, thus preventing such dual conversion and facilitating access to a greater number of independent audio channels.
This type of equipment, dedicated exclusively to audio recording, make production much more flexible, since it allows increasing the number of independent channels that will later be treated with much greater efficiency in the post-production stage. Being able to control each channel separately ensures that it will be much easier for the final assembly to re rendered much cleaner, by emphasizing or attenuating each source separately at all times.
The simplest already offer several independent channels and the most sophisticated ones even have a time code capture, which is very convenient for subsequent syncing with the image. If you don’t have it, don’t forget to use a clapperboard at the beginning of each take, which also makes subsequent synchronization much easier. And don’t let anyone say they don’t have one because, in the worst-case scenario, just a clap in front of the camera is an emergency solution that has been around for decades.
The range of models is wide, and we will only have to ensure operation if we want it to be autonomous, the number of channels available to suit our needs, storage options, which are usually memory cards, and the connections, which will typically be XLR.
This device is that flapped frame that is placed in front of the lens to act as a lens hood and prevent stray light from entering the lens, thus avoiding the effects caused by flaring and undesired haloes. We will choose a model that comes with one, three or four flaps depending on the directions from which we need to avoid the stray light. We will have to adjust the flaps depending on the focal length of the optics in use so as to avoid darkening the image.
They are supported on the same type of rig as mentioned in the optics remotes and, depending on the manufacturer and model, they also work as filter holders. In this case, it will be important to make sure that size is sufficient to avoid vignetting effects. It is advisable to choose an oversized matte box it since the filters, once mounted, will be at a certain distance from the front lens.
Another endless range Build quality is absolutely critical, since it is of little use to invest a significant part of the budget in excellent optics, if they are going to be fitted behind glass that adds unwanted imperfections. Fortunately, the range is very wide and there is a lot to choose from.
In this section it is interesting to classify the options by construction: round, to be screwed directly onto the optics and which must have the exact diameter or use a larger one with an adapter; and square or rectangular ones, without frame, to mount on the filter holder or matte box. In this case, close attention must be paid to the different standard measures, always considering the exception mentioned in the section of matte boxes for the filter holders.
And in terms of types, the most common ones are the ND, os as to dim the amount of light and work with more open diaphragms, or those for conversion of color temperature, polarizers, gradients, color … The options are endless.
Just one last note before closing: We must take into account that the filters also exist in a flexible format, in rolls of about one meter wide and several meters long; and they are the ones that we will use to control or tint the different light sources, thus opening up a new and enormous range of creative possibilities.
This is yet of those sections for which we could create a full feature. Like all electricity storage devices, its two main technical features are voltage (in volts) and capacity (in Ah, or ampere-hour). But in reality, they are very easy to classify because their distinct feature is always the type of media and connection.
Each manufacturer has its own proprietary format for the smallest models, while the large ones, similar in size (and weight) to building bricks, tend to meet some standards. In this case, we would dare to say that one of the most common stardards does not belong to a camera manufacturer, but to a company that is mainly dedicated to the design and manufacture of batteries.
In the case of small batteries, given the specificity of the model required for each camera, we are faced with a curious dilemma: there is not much to choose from for each camera model, but we could need different batteries if we use different ranges of cameras, even if from the same manufacturer.
Once the required model for our camera(s) is known, the dilemma will be whether to use the original brand model or a generic model from other manufacturers. Our experience tells us that original ones tend to have the best compatibility, performance, reliability, and long-term charge and discharge life cycles. In third-party manufacturers it is possible to find batteries that come close to such specifications at somewhat lower prices. But if we go for models with a clearly lower price, we can be sure that the difference in features will be significant. And there are situations that can be very awkward, such as working in environments with temperatures or humidities other than the comfortable ones. The turning point here will be in the balance between budget and reliability needs.
When dealing with large batteries, it is much easier to find some models with excellent features and benefits that equal -and even exceed- those offered by the camera manufacturer itself.
Another aspect to keep in mind will be that batteries are not “camera accessories”, but they are also “accessores for accessories”. This is because many of the accessories discussed in this article also need them to function, such as external recorders, wireless transmitters or torches that we will see below.
Torches are small sources of continuous light that we generally use to fill in the illumination of subjects at close range. They were more necessary in the times when the sensors were less sensitive than the current ones, but their high consumption made the power supply heavy and limited.
Since the advent of LED lighting technology -with a light output that allows significant amounts of light for reasonably long periods of time and with a wide range of adjustment in both color temperature and intensity- a meaningful use has been found for them once again.
Their main purpose will not be to illuminate the scene since, being relatively close to the subject, they tend to generate very harsh highlights and shadows. But in ENG or feature report environments, they are very suitable for filling shadows, attenuating the effect of an intense side source, and even providing that sparkle that we like so much in the eyes of our protagonists.
Ideally, they should be lightweight and offer good performance so that the batteries provide us with the maximum usage time. Other features that we should assess will be if they allow adjusting intensity, color temperature or whether they come some type of diffuser or color filter.
There are camera manufacturers that also offer this device as an accessory. In these cases, we find some other interesting additional feature worthy of assessment like all the others, such as the possibility of turning it on and off in synchronization with the recording or taking the power from the camera itself. Although this feature is very handy, it will not always be the best solution. As usual, to be considered based on the needs of our projects.
Since this is another one of those devices that requires power to operate, and given the huge number of manufacturers currently available, each one often chooses to manufacture with battery holders that are compatible with the standard models of the main camera manufacturers.
Adjustment charts and color charts
These easy-to-use items are part of a number of little things that we can’t live without once we’ve tried them. They consist of a holder with patches of different colors and exist in different sizes. The purpose is to optimize the exposure setting and color reproduction with minimal effort.
Once we have our scene set up, with the camera angle and lighting properly determined, at the time of filming they help us to establish the correct exposure, making it easier for the latter to adjust to the most important parts of the scene or on which we are trying to focus our attention. Later, while the takes required for our production are being shot, other takes are shot with these cards in the same position as our protagonists.
These are the takes that we will later use in grading to adjust the color. To do this, and as long as we have the appropriate monitors and sufficient experience and training, we can use a mere comparison to adjust or divert the color towards the result we want.
And making it even easier for those without all the experience and tools, some of the current color correction applications can identify the patches from those cards and make, nearly instantantly and with extreme accuracy, a first correction adjustment of color that in many cases will be enough to offer a very good result to our clients.
This has been part one. In the second and final part we will continue to expand our catalog including a large number of specific elements for the broadcast world and we will also leave some space to cover off-camera lighting equipment.