some reflectors have a small button on his back, to allow the fit of your focus. By adjusting this button, the area covered by the beam reflector in front can open or close . By moving the button the internal base where the lamp reflector is installed is brought back ( more on the bottom of the reflector) or pushed forward . Before moving back, the beam emitted by the reflector becomes smaller ( closed) . The reverse occurs when moving the base forward . Together with the adjustment of barndoors ( adjustable movable flaps have many reflectors ), this control mechanism can be used to refine and shape the surface to be illuminated . To make the adjustment , initially all barndoors should be opened . Next, adjust the knob of the focus of the reflector , opening or closing the beam to the desired position . Only after this is that bardoors must be moved , if necessary , shaping by controlled interruption of lumen area to be illuminated by spotlight.
Color Tuning & monitor
the most accurate way to make adjustments to colors in the image is not the same watching through the camera viewfinder or LCD display but through an external monitor , which connects to the video output of the camera. If a professional monitor is not available, a portable TV aparelhor can do this function , since it has video input ( composite video generally represented by a female connector RCA , yellow in color , on the back of the unit) . The screens reduced size of the viewfinder / LCD do not allow the visualization of color tints with the same precision as the display screen . As a prerequisite however , the monitor / TV set should be correctly adjusted for color reproduction . This adjustment is achieved , among other ways , by displaying an image of color bars , the banding pattern of colorful colors that allows you to make adjustments of hue, brightness and contrast . Some camera models of semi - professional segment can generate color bars signal and there are electronic devices that also make this function .
White Balance & changes
the lease remember to make the adjustment of white ( white hit ) whenever the lighting conditions of the local change ( new lit / lights , time of day , cloud / sun ) , the site itself is changed or even , depending on the case, the position of the camera ( where the same points ) change, if things go to frame / enlightened people through light sources with different temperatures compared to what was framed before. Of course in some situations such as concerts for example, the variation in shade and color intensity from the same part , in which case the automatic camera shake must be shut down and the same set to some pre- defined position , such as for example interior light . This situation may present before the beginning of the show when the prevailing lighting is usually neutral .
white balance , location and
fill the display should be careful , when making manual adjustment of white ( white hit ) , ensure that the object of white color for which the camera points during adjustment receives the same illumination that the object / person be recorded. On a simple example, it would be incorrect place setting pointing to a card located in the shade , where is also the camera when the image is recorded of a person who is in the sun Furthermore , to make the adjustment , the camera must totally frame the white object , to prevent the invasion of different colors that could alter the accuracy of the fit .
white balance in post production
the ideal is to capture images with the white balance set correctly , either in existing automatically with some cameras is in manual mode . However , in post -production , you can " hit the white " digitally , by an action of this type exists in some editing programs . The result will not be accurate as that obtained during the capture phase , but can "save " captured without having done the correct fit images . The function works to inform the program a particular portion of the picture that should be considered white. The system then adjusts the proportions of the basic RGB colors in the scene in order to balance the general coloring , as would occur if the same had been done in the camera , the moment of capture .
white balance for the purposes
Interesting effects can be achieved on the image to make himself mistakenly white balance . Thus, by using the setting for outdoor scenes in interior scenes , the images have an orange tone. The reverse will cause bluish tones . You can go further and use the rate for white camera , but instead of using a card or white wall , making this beat using surfaces or places with other colors . So the beat on the display framing the blue sky will make images appear with a sepia tone eg fluorescent lamps or cause pink tint in pictures outdoors. And so on , several options may be tried and experimented .
white balance for the purpose , enhancing the setting of the sun
scenes from the setting sun can be manipulated by manually adjusting the white balance on the camera . Orange and red tones can be highlighted when you point the camera ( with auto off setting ) for a slightly bluish object and follow some procedures described below . First, the object ( a sheet of paper , a cloth , etc ... ) should occupy preferably the majority of the image when viewed on the camera display . After doing so, trigger the button on the camera ( some devices may not have this control ) to perform manual adjustment of white ( white balance ) . Then , without changing the adjustment made, point the camera at the scene of the setting of the sun . When the adjustment is made for the blue object , control of exposure increases the proportion of reddish tones in the image , trying to compensate for the excess of blue ( the object ) . And with that achieves the desired enhancement.
barndoors & jellies
There are two ways to fix a sheet of gelatin in front of a reflector : or cutting it in the form of the glass that covers it and fixing it or bending it so that its borders secure them with special clips ( or fasteners clothes on the clothesline - in this case observe with care the heat generated ... ) in barndoors , the metal plates that serve to direct the spotlight . Fixing the barndoors has the advantage that if you cut the sheet , allowing its use on other occasions . However, this practice change the final result obtained . When set in barndoors , due to the greater distance between the lamp and the effect will be a gelatin softened light. Moreover , it should be noted that fixing the barndoors completely eliminates the function of them: the surface of the gelatin now becomes the new light source , acting like a spotlight devoid of barndoors .
laptop card to beat the white
while doing the beating of white on a lease, any white object can be used , such as walls , t-shirts , papers , etc ... However , in certain places can be hard to find a white surface or at least that is not a dirty white now due to use and time. So the tip is to load in case the camera is always a small card ( can be eg 15cm x 20cm ) for this purpose . The card can be mounted folding and gluing with adhesive tape on the back of a sheet of typing paper on a card or hard cardboard. Overlap two sheets of bond helps to give more intensity to white - the leaf , being slightly translucent , you can leave "leak " to the background color of cardboard . In time to hit the white, the card must be placed where objects / Spare to be written so that you receive the same light they are receiving . With câmrera fully fit on the display card and then make the adjustment of white.
guard card
car used in the folding card that usually puts on the dashboard to protect it from the sun can serve as an excellent hitter into the light , especially the foil type , with the advantage in this case it can be used on both sides, aluminized to reflect more closely the light and the opposite (if white ) for a softer light .
night scenes in landscapes
the best time for capturing night scenes outside is not at night but at dusk . During the evening , the landscape is still a little unclear : facades of buildings are still visible , as well as clippings of branches and foliage . It turns out that the light sensitivity of the video is much smaller than the human eye ( in normal situations , with the gain- up function off - . This function artificially amplifies the video signal to be recorded , causing granulation , among other problems and also without the use of " night vision " infrared ) . Thus , in situations where the human eye sees at night detail of the facade of a dark and poorly lit building to the video image will be uniformly black . Thus, the " clock " dusk / dusk / night should be attempted to conduct nighttime images .
rain (artificial ) lighting and
rain can be simulated playing up to the high water from a hose with a cap ( of type ' showerhead ' ) at the tip . This spreader device can be found in garden shops . The greater the height reached by the best water ( you can use a ladder as an aid ) . Note that the jet should always be thrown up , never down, if you are being evicted by a person on the ground or even on top of a ladder . In the professional area, usually a different approach is used , with a network of sprinkers ( spreaders water) suspended at a good height , directing , yes here , the water straight down .
Both in one case as in the other , so the camera can ' see ' the drops falling , you must light them laterally to the angle of vision of the camera , with a very powerful source of light ( remember that although it may rain with sun usually occurs rain or overcast evening and these situations are better accepted by the viewer , ie , the illusion works best ) . To further improve the visualization of the droplets , the background should be dark . As an example , a black opaque plastic , suspended in order not to get too close to the foreground ( person or object being recorded) , with several plants across the same . All this background will be blurred .
freezing
image & light through this effect , where the speed of ' electronic shutter ' camera ( high speed shutter function ) , increases up -time you can analyze frame by frame playback rapid movements recorded on the tape . However , by increasing the shutter speed , and exposure time will fall , less light is used to record the image : it will be dark . This is compensated by increasing the aperture of the lens , or function performed automatically by the camera or the operator (if disabled in automatic mode ) . This increased openness will result in a decrease of the depth of focus. If this is not the problem , the result will be satisfactory . However , if this is a problem , you need to illuminate the scene with more light : the greater the amount of light , unless the diaphragm need to be open and therefore the greater the depth of field obtained .
Cookies : Controlling the definition of the projected edges
cookies ( plates , usually metal - to withstand the heat of the light - with perforations in the form of drawings used to design jagged shadows on a surface ) are very useful in composition scenarios . Placed in front of a reflector , allow designing interesting designs on the background of the scene . Marketed in countless variations of designs can be fitted with appropriate colored gelatins . When installed in reflectors with lens , design well-defined shadows . When placed in front of common reflectors however , can cast shadows with more or with less definition . As far as a luminous flux an opaque object is , the more accurate the shadow cast by the same , placing the cookie farther from the reflector, the design will have more defined look , placing it closer to the reflector, the appearance will be smoother . Importantly , in this case ( on cookie devoid of reflector lenses) , the spotlight that "leaks " out of the cookie area should be protected with the use of barndoors ( adjustable movable flaps that many have reflectors ) or else flags (or flags , small opaque flat plates fixed in order to stop the flow of light of the same ) .
controlling unwanted reflections
Light can be molded and worked in favor of the desired goal , which can be achieved in part by appropriate reflectors. To get yourself however full control over it , the use of barndoors ( mobile flaps that many have reflectors on its 4 sides) and flags (or flags , pieces of flat plates , opaque , set in strategic locations is necessary to stop the passage of light ) . Moving these elements carefully , can be very interesting lighting effects , especially in the studio , to make funds scenarios . The light that passes through a cookie for example ( plate with holes shaped designs , used to cut cast shadows on a surface ) can be shaped through the proper adjustment of the reflector barndoors . Thus, it is possible to concentrate only on the area of the cookie and design in drawing only the desired setting, without competition from unwanted reflections of its sides . The more precise " cut " Shadow however is done through the flag , because it is usually positioned further away from the spotlight - and the barndoors are very close to it , in fact , set in itself. The farther you are from the obstacle , more defined luminous flux is the shadow cast by the same .
converting footcandle lux
some photometers ( meters luminous intensity ) may present in their viewers a range of footcandle type ( an old measure of light intensity ) . If it is desired to use such an apparatus for measuring the lighting an object / person subject for the purpose of comparison with the specification given recording camera ( typically specification taken in lux ) is required to perform a conversion values . For this conversion, it can be considered approximately one footcandle valley 10.7 lux.
Fixing rayban glasses
when making recordings in classrooms and offices with large glass areas , it is possible to face with glasses slightly greenish tint as the type rayban glasses . Sometimes the green cast can be very subtle , and as the human eye adapts to situations of change of temperature of light can pass unnoticed . A good practice is to always hit the white before writing , but if for some reason this was not done at a site of this type , a slightly greenish tint to the image will be perceived at the time of issue and shall then be corrected . The simplest way is to access the control intensity of the basic colors in RGB image and decrease slightly ( slightly ) green . Or make the digital adjustment of white , found on some programs - see the hint " white balance in post production ." The first in this situation can be more precise , by relying on the feeling of the human eye during adjustment. The easiest way to notice the problem is pay attention to people's skin , lacking a more reddish hue ( which suggests health, unlike the greenish tone that suggests the disease - including this color is traditionally used in colored comics to represent this situation ) .
cromakey
Briefly , some tips for a good cromakey is uniformly illuminate the background, keep the person / object of the first distant plane of the bottom , do not allow to form shadows in the background from the lighting used for the foreground and not let the lighting background " contaminate " the foreground.
cromakey : circumventing the limitation of screen size
sometimes , depending on the effect you want to achieve , the size of the screen in the studio cromakey available may be insufficient . One example is to add the image of a person within a football field , seen from one side of the lawn, where the image of that person occupies one third of the height of the image frame of the video. The most dispendiciosa alternative is to get a " giant" , a local idem screen and all necessary lighting. The economical, however , allows you to easily perform the effect in the editing stage - nonlinear . In editing software , the image of the person with the small screen cromakey the background should be reduced , making the effect of picture-in -picture on a clean track in the Timeline in another picture. Next, select background color for this clean image the same background color cromakey . To merge the two images in the composition of the tracks has been reduced to about one person "bottom" of cromakey much larger than the original size. Just then make the cut through the function cromakey .
cromakey : checking the quality of the backlighting
a way to check if the background is evenly lit is only record a few seconds with this appearing on the display . Next, using a monitor wavelength, which may be hardware type ( waveform monitor , similar to a physical machine to a video monitor which connects the video signal to be analyzed ) or software ( function waveform existing in various programs for non-linear editing , which opens a window with a representation of what would be shown on the actual device screen ) , verify the uniformity of green along the frame of the scene : there should be a straight line in its statement . To prove , in the last seconds of recording test above , ask a person to stand in front of the screen . The indication on the waveform monitor should change right now.
cromakey and adjust lighting the foreground
a tip to make the adjustment of the lighting in the foreground in an assembly of the type which employs cromakey independent illuminations background and foreground , is totally off the backlighting . Next, make all adjustments in foreground lighting through positioning of reflectors , and also their barndoores additional flags . Always keep in mind , during this adjustment , if any of these lights is reaching the bottom - a fact that should not occur .
cromakey and real-time adjustment
a tip for better fit in cromakey is setup to connect the camera output directly to the input of the capture card into a system of non - linear editing on site . So you can , in real time , making all the necessary adjustments and positions between the elements of the foreground , background and spotlights the best condition to be obtained .
cromakey and beat the white
in an assembly to cromakey where a person stands in front of the background that will be cut, adjusting the white should be done excluding the background. To do so , place the card in front of the person and zoom in the camera , the angle close to fully fit the card in the display . Then adjust the white on the camera catching it below. Done catching, return the environment to its original position .
cromakey and distance from the camera to the bottom
a useful measure is to keep the camera at a good distance from the foreground , and so use the zoom in tele position to make the shot. By doing this, the depth of field decreases to a small strip to the front and back of the person in the foreground , failing to reveal any imperfections in the background , once it ceases to be sharply focused .
cromakey and camera movement
recordings of a person in front of a screen cromakey the tip is to avoid as much move the camera . The light settings and positioning of the person has to be accurate , and unless the light set + background is extensive and uniform movement will have an effect of ' esfumaçamento ' ( blur) the image contours , especially if you are using some of the group DV formats .
cromakey and movement of the person
the person who is being recorded on a background for cromakey must move without making sudden movements : these have a tendency to cause a esfumaçamento the image ( blur) which finishes merging with the background, undermining the illusion . The problem is more apparent in formats utlizam lower color resolution in the image , such as the DV format .
cromakey and positioning of the camera relative to the background
the trick is to keep the camera perpendicular to the plane of the bottom . Thus , it should not be too high on the tripod and tilted down or too low and tilted upward . An extreme measure is to check their level of alignment with the aid of a level . On the other hand , lateral angles should also be avoided , the camera should always be facing the screen. In all the above situations , the background will be very slightly closer to one side of the CCD plane than the other, affecting the intensity of light that side - light more intense than the other side. This unequal brightness , depending on the sensitivity setting cromakey can affect the quality of the process , causing some areas do not become fully transparent .
cromakey and foreground glow
the presence of bright objects in the object / person to be trimmed should be avoided , especially when located at the edges of the contours of the same . The brightness at the edges causes the clipping ceases to be a line defined contour relative to the background . The problem can occur for example when cutting an object of stainless steel or a bald person . The trick is to use these objects or people resources to reduce glare - there are specific products for this such as anti -reflective sprays .
cromakey and chalkboard
a school box ( for blackboard chalk) can be improvised as the background for cromakey . The framework must be the green kind , to be with his new and well washed surface free of scratches and flaws , and uniformly illuminated . Herself lighting commonly used at these sites ( fluorescent lights ) can achieve a uniform way the box be used for backlighting ( the box ) .
cromakey and shadows in the background and foreground
if the intention is to integrate the foreground to the background ( a person be " placed " on a beach where it is not for example) , you should pay attention to the lighting of the " background " and foreground , which must be consistent. As " background " here means not cromakey the lighting of the screen itself , but the existing lighting in the place whose image will replace the green screen . Thus , if the sun this beach produces shadows in the trees and others from right to left , in the studio , the person must have the reflector head light also moved to this position . An inversion become inconsistent effect , calling the attention of the viewer for this integration disharmony person / environment.
cromakey and fabrics used in clothing
should be avoided wearing clothes with designs of lines (bands ) very close next to each other . The use of fabrics with these standards entails an effect known as moiree Pattern ( default moiree ) , where these lines are presented with shimmering effects in the image . This effect (which appears even in non- cromakey recordings ) can lead to problems during the cropping of the image especially with the use of digital formats from DV family because scintillations are presented in the form of strange artifacts in the image , these artifacts that carry various colors. Thus, it is possible to have the colors in the input foreground image that correspond to the background , making the parts which are to become -( incorrectly) transparent .
cromakey different temperature and light in the foreground and background
the fund cromakey can be illuminated with totally different foreground in terms of color temperature light if a condition is met: the two illuminations are completely independent . Thus, it is possible for example to employ cold light to illuminate the background and incandescent light to illuminate the foreground : the camera , the beating of the white should be made with light foreground , not the background light . By watching the monitor , after whipping the bottom will get a bluish tint , however this is no problem : simply select this color for the compositing program - and remember not to use it in foreground elements .
cromakey and artificial wind
illusion caused by an effect of cromakey on an external image ( beach, open field for example) can be well emphasized to the viewer if a fan is placed next to the person to be cropped in the foreground . Adjusted for blowing the equivalent of a breeze on the clothes of the person ( the hair cromakey should be fixed preferably with gel) making it vibrate slightly , makes extremely convincing effect. The caution to be taken is to check whether the background image is no wind and which way it blows , to maintain the same direction in the foreground .
cromakey outdoors
You can make pictures of the process of composition utlizando cromakey in outdoor environments , without using a specific screen for chroma . Thus , the background may be the blue sky for example (from a low outlet , bottom-up , which excludes items other than the sky ) . Or walls and facades that have uniform color . The tips are blur the background ( far from the same person ) , possible to hide imperfections like seams of bricks , cracks , etc. ... And use the RGB color matching surface , beyond the yellow.
cloudy days
are excellent for close- ups , especially of people: those days sunlight is not direct, is well diffused because of the clouds . The light rays come from various directions , which makes the shadows cease to be pronounced and areas gain even illumination , causing a pleasing appearance of smoothness .
diffuser screen
when recording scenes of a person talking to the camera directly under sunlight , it can be observed , depending on the intensity of it, and the effect caused by the harsh shadows and high contrast locations on the face of the person . Rather than change the save location for the shade , an efficient solution to the situation is to soften the sunlight , through a diffuser screen . In a very large wooden frame or PVC tubes (preferred for lightness and ease of construction) can mount the diffuser extending over the frame and securing it in the same medium to a screen frame ( voile for example) tissue . Screens in black work best . At a distance of about 2 to 3m of the person for example, the diffuser is suspended so as to cause a 'shadow' on the person actually an attenuation of strong and hard ( light that causes well-contrasted shadows ) sunlight.
dimmer for controlling the light intensity
in situations where basic light kits of the consumer or even semi- professional type are used , an alternative to smooth or reduce the intensity of light is common to use a dimmer . Can be constructed a device consisting of a box in which , on one of its surfaces , control of the dimmer with the unit is installed inside . Leave the device input and output cables , fitted with male / female plugs on the ends . It is essential that the whole construction is made with heat resistant materials , flame retardant yarn (which is now currently a standard cable industry ) , plugs first line and that all connections are correctly mounted , wireless or screws not well established . This procedure must be followed naturally in all types of electrical installation . The other point to note is that the dimmers are manufactured to work with a certain capacity threshold ( wattage ) . Thus, the sum of the power of the lamps connected to it must be less than this capacity. Finally , note that not all bulbs are dimmable , especially those of common fluorescent type . Met these observations , one can have a handy device , handy for when you need to reduce the intensity of light without resorting to filters placed in the spotlight . As a final note , remember that the reducing power of the lights will need to make the adjustment of white again ( if not already done and if the goal is to produce a display with true color to reality ) .
disguising skin problems
to disguise , in the image , excessive wrinkles and / or imperfections in skin texture , the trick is to soften the lighting. As these imperfections constitute irregularities in the surface relief of the skin , the light it receives may be partially blocked in several passages , creating tiny shadows that accentuate the contrast between the flatter parts . One can compare the effect to a flat and smooth terrain, which does not produce shadows when lit by the sun and full of ups and downs in the terrain relief . These ups and downs produce shadows when light hits them at a flat angle . These shadows more than the actual irregularity of the relief, mean that there is a sharp contrast between light and dark parts . In other words, if there were no shadows , the image would be more uniform and smooth. In very small scale is what happens on the surface of the skin . So all you can do is try to reduce these shadows . For this, some alternatives can be attempted. One is to avoid side lighting , giving preference to the front lighting of the face ( equivalent to Sun noon in contrast to the beginning or end of the day ) . Another use soft light , no light " lasts " : There smoothing gels that can be used on reflectors , or soft boxes called softbox , always arranged frontally . Another way out is the use of a smoothing filter on the camera lens or still a smoothing effect in the post - editing - applied with little intensity.
avoiding duplicate shadows
in an assembly with reflectors to illuminate a person standing next to a wall background, runs the risk of the spotlight produce different shadows on this background, a result that may have amateurish aspect or agitated then remember interviews where several stations TV position their equipment while promptly to capture some statement of the respondent. If two reflectors for example , it is acceptable that the shadow of one of them is projected on the wall , but not both. In this case , simply position of the reflectors directly facing the person's face - but located laterally to it - without caring about the shadow that forms the background. This will be the main light in a main / fill scheme . The second reflector ( field) should be placed on the other side , preventing its light reaches the bottom , or through its rotation turned slightly away from it, or via a flag ( opaque reflector plate placed next to the spreads its light ) . Placed farther from the face of the person , allow the creation of a softer light , thus causing the highlight of the three-dimensional aspect of the face.
excess light
ND filter and contrary to what one might imagine , the more light is not always best : in this situation , the bright colors begin to become saturated and the image lacks in definition . To circumvent this problem , common in very bright environments ( beach, snow for example) a filter type ND ( Neutral Density ) can be added to the camera lens. This type of filter , which exists in various degrees , does not change the colors of the recorded image , only reduces the intensity of light that reaches the camera lens , allowing better exposure of the subject .
fixing reflectors in doors
a door can be used in emergency situations where there is no traditional supports available to fix a reflector . The idea is to use clamps with powerful springs , coated with rubber or plastic material ( found at hardware stores ) . The clamp is fixed at the top of a door, must be set slightly open - both use a pad underneath it. The clamp via a tight and secure fit is used to hold the reflector at the top of the door. Other locations may also be used for fixation .
fluorescent
can be used without problem as artificial light source , since it Take care to make up the balance in color temperatures that illuminate the person / object. If only fluorescent lights are used , use the automatic white -balance the camera
Color Tuning & monitor
the most accurate way to make adjustments to colors in the image is not the same watching through the camera viewfinder or LCD display but through an external monitor , which connects to the video output of the camera. If a professional monitor is not available, a portable TV aparelhor can do this function , since it has video input ( composite video generally represented by a female connector RCA , yellow in color , on the back of the unit) . The screens reduced size of the viewfinder / LCD do not allow the visualization of color tints with the same precision as the display screen . As a prerequisite however , the monitor / TV set should be correctly adjusted for color reproduction . This adjustment is achieved , among other ways , by displaying an image of color bars , the banding pattern of colorful colors that allows you to make adjustments of hue, brightness and contrast . Some camera models of semi - professional segment can generate color bars signal and there are electronic devices that also make this function .
White Balance & changes
the lease remember to make the adjustment of white ( white hit ) whenever the lighting conditions of the local change ( new lit / lights , time of day , cloud / sun ) , the site itself is changed or even , depending on the case, the position of the camera ( where the same points ) change, if things go to frame / enlightened people through light sources with different temperatures compared to what was framed before. Of course in some situations such as concerts for example, the variation in shade and color intensity from the same part , in which case the automatic camera shake must be shut down and the same set to some pre- defined position , such as for example interior light . This situation may present before the beginning of the show when the prevailing lighting is usually neutral .
white balance , location and
fill the display should be careful , when making manual adjustment of white ( white hit ) , ensure that the object of white color for which the camera points during adjustment receives the same illumination that the object / person be recorded. On a simple example, it would be incorrect place setting pointing to a card located in the shade , where is also the camera when the image is recorded of a person who is in the sun Furthermore , to make the adjustment , the camera must totally frame the white object , to prevent the invasion of different colors that could alter the accuracy of the fit .
white balance in post production
the ideal is to capture images with the white balance set correctly , either in existing automatically with some cameras is in manual mode . However , in post -production , you can " hit the white " digitally , by an action of this type exists in some editing programs . The result will not be accurate as that obtained during the capture phase , but can "save " captured without having done the correct fit images . The function works to inform the program a particular portion of the picture that should be considered white. The system then adjusts the proportions of the basic RGB colors in the scene in order to balance the general coloring , as would occur if the same had been done in the camera , the moment of capture .
white balance for the purposes
Interesting effects can be achieved on the image to make himself mistakenly white balance . Thus, by using the setting for outdoor scenes in interior scenes , the images have an orange tone. The reverse will cause bluish tones . You can go further and use the rate for white camera , but instead of using a card or white wall , making this beat using surfaces or places with other colors . So the beat on the display framing the blue sky will make images appear with a sepia tone eg fluorescent lamps or cause pink tint in pictures outdoors. And so on , several options may be tried and experimented .
white balance for the purpose , enhancing the setting of the sun
scenes from the setting sun can be manipulated by manually adjusting the white balance on the camera . Orange and red tones can be highlighted when you point the camera ( with auto off setting ) for a slightly bluish object and follow some procedures described below . First, the object ( a sheet of paper , a cloth , etc ... ) should occupy preferably the majority of the image when viewed on the camera display . After doing so, trigger the button on the camera ( some devices may not have this control ) to perform manual adjustment of white ( white balance ) . Then , without changing the adjustment made, point the camera at the scene of the setting of the sun . When the adjustment is made for the blue object , control of exposure increases the proportion of reddish tones in the image , trying to compensate for the excess of blue ( the object ) . And with that achieves the desired enhancement.
barndoors & jellies
There are two ways to fix a sheet of gelatin in front of a reflector : or cutting it in the form of the glass that covers it and fixing it or bending it so that its borders secure them with special clips ( or fasteners clothes on the clothesline - in this case observe with care the heat generated ... ) in barndoors , the metal plates that serve to direct the spotlight . Fixing the barndoors has the advantage that if you cut the sheet , allowing its use on other occasions . However, this practice change the final result obtained . When set in barndoors , due to the greater distance between the lamp and the effect will be a gelatin softened light. Moreover , it should be noted that fixing the barndoors completely eliminates the function of them: the surface of the gelatin now becomes the new light source , acting like a spotlight devoid of barndoors .
laptop card to beat the white
while doing the beating of white on a lease, any white object can be used , such as walls , t-shirts , papers , etc ... However , in certain places can be hard to find a white surface or at least that is not a dirty white now due to use and time. So the tip is to load in case the camera is always a small card ( can be eg 15cm x 20cm ) for this purpose . The card can be mounted folding and gluing with adhesive tape on the back of a sheet of typing paper on a card or hard cardboard. Overlap two sheets of bond helps to give more intensity to white - the leaf , being slightly translucent , you can leave "leak " to the background color of cardboard . In time to hit the white, the card must be placed where objects / Spare to be written so that you receive the same light they are receiving . With câmrera fully fit on the display card and then make the adjustment of white.
guard card
car used in the folding card that usually puts on the dashboard to protect it from the sun can serve as an excellent hitter into the light , especially the foil type , with the advantage in this case it can be used on both sides, aluminized to reflect more closely the light and the opposite (if white ) for a softer light .
night scenes in landscapes
the best time for capturing night scenes outside is not at night but at dusk . During the evening , the landscape is still a little unclear : facades of buildings are still visible , as well as clippings of branches and foliage . It turns out that the light sensitivity of the video is much smaller than the human eye ( in normal situations , with the gain- up function off - . This function artificially amplifies the video signal to be recorded , causing granulation , among other problems and also without the use of " night vision " infrared ) . Thus , in situations where the human eye sees at night detail of the facade of a dark and poorly lit building to the video image will be uniformly black . Thus, the " clock " dusk / dusk / night should be attempted to conduct nighttime images .
rain (artificial ) lighting and
rain can be simulated playing up to the high water from a hose with a cap ( of type ' showerhead ' ) at the tip . This spreader device can be found in garden shops . The greater the height reached by the best water ( you can use a ladder as an aid ) . Note that the jet should always be thrown up , never down, if you are being evicted by a person on the ground or even on top of a ladder . In the professional area, usually a different approach is used , with a network of sprinkers ( spreaders water) suspended at a good height , directing , yes here , the water straight down .
Both in one case as in the other , so the camera can ' see ' the drops falling , you must light them laterally to the angle of vision of the camera , with a very powerful source of light ( remember that although it may rain with sun usually occurs rain or overcast evening and these situations are better accepted by the viewer , ie , the illusion works best ) . To further improve the visualization of the droplets , the background should be dark . As an example , a black opaque plastic , suspended in order not to get too close to the foreground ( person or object being recorded) , with several plants across the same . All this background will be blurred .
freezing
image & light through this effect , where the speed of ' electronic shutter ' camera ( high speed shutter function ) , increases up -time you can analyze frame by frame playback rapid movements recorded on the tape . However , by increasing the shutter speed , and exposure time will fall , less light is used to record the image : it will be dark . This is compensated by increasing the aperture of the lens , or function performed automatically by the camera or the operator (if disabled in automatic mode ) . This increased openness will result in a decrease of the depth of focus. If this is not the problem , the result will be satisfactory . However , if this is a problem , you need to illuminate the scene with more light : the greater the amount of light , unless the diaphragm need to be open and therefore the greater the depth of field obtained .
Cookies : Controlling the definition of the projected edges
cookies ( plates , usually metal - to withstand the heat of the light - with perforations in the form of drawings used to design jagged shadows on a surface ) are very useful in composition scenarios . Placed in front of a reflector , allow designing interesting designs on the background of the scene . Marketed in countless variations of designs can be fitted with appropriate colored gelatins . When installed in reflectors with lens , design well-defined shadows . When placed in front of common reflectors however , can cast shadows with more or with less definition . As far as a luminous flux an opaque object is , the more accurate the shadow cast by the same , placing the cookie farther from the reflector, the design will have more defined look , placing it closer to the reflector, the appearance will be smoother . Importantly , in this case ( on cookie devoid of reflector lenses) , the spotlight that "leaks " out of the cookie area should be protected with the use of barndoors ( adjustable movable flaps that many have reflectors ) or else flags (or flags , small opaque flat plates fixed in order to stop the flow of light of the same ) .
controlling unwanted reflections
Light can be molded and worked in favor of the desired goal , which can be achieved in part by appropriate reflectors. To get yourself however full control over it , the use of barndoors ( mobile flaps that many have reflectors on its 4 sides) and flags (or flags , pieces of flat plates , opaque , set in strategic locations is necessary to stop the passage of light ) . Moving these elements carefully , can be very interesting lighting effects , especially in the studio , to make funds scenarios . The light that passes through a cookie for example ( plate with holes shaped designs , used to cut cast shadows on a surface ) can be shaped through the proper adjustment of the reflector barndoors . Thus, it is possible to concentrate only on the area of the cookie and design in drawing only the desired setting, without competition from unwanted reflections of its sides . The more precise " cut " Shadow however is done through the flag , because it is usually positioned further away from the spotlight - and the barndoors are very close to it , in fact , set in itself. The farther you are from the obstacle , more defined luminous flux is the shadow cast by the same .
converting footcandle lux
some photometers ( meters luminous intensity ) may present in their viewers a range of footcandle type ( an old measure of light intensity ) . If it is desired to use such an apparatus for measuring the lighting an object / person subject for the purpose of comparison with the specification given recording camera ( typically specification taken in lux ) is required to perform a conversion values . For this conversion, it can be considered approximately one footcandle valley 10.7 lux.
Fixing rayban glasses
when making recordings in classrooms and offices with large glass areas , it is possible to face with glasses slightly greenish tint as the type rayban glasses . Sometimes the green cast can be very subtle , and as the human eye adapts to situations of change of temperature of light can pass unnoticed . A good practice is to always hit the white before writing , but if for some reason this was not done at a site of this type , a slightly greenish tint to the image will be perceived at the time of issue and shall then be corrected . The simplest way is to access the control intensity of the basic colors in RGB image and decrease slightly ( slightly ) green . Or make the digital adjustment of white , found on some programs - see the hint " white balance in post production ." The first in this situation can be more precise , by relying on the feeling of the human eye during adjustment. The easiest way to notice the problem is pay attention to people's skin , lacking a more reddish hue ( which suggests health, unlike the greenish tone that suggests the disease - including this color is traditionally used in colored comics to represent this situation ) .
cromakey
Briefly , some tips for a good cromakey is uniformly illuminate the background, keep the person / object of the first distant plane of the bottom , do not allow to form shadows in the background from the lighting used for the foreground and not let the lighting background " contaminate " the foreground.
cromakey : circumventing the limitation of screen size
sometimes , depending on the effect you want to achieve , the size of the screen in the studio cromakey available may be insufficient . One example is to add the image of a person within a football field , seen from one side of the lawn, where the image of that person occupies one third of the height of the image frame of the video. The most dispendiciosa alternative is to get a " giant" , a local idem screen and all necessary lighting. The economical, however , allows you to easily perform the effect in the editing stage - nonlinear . In editing software , the image of the person with the small screen cromakey the background should be reduced , making the effect of picture-in -picture on a clean track in the Timeline in another picture. Next, select background color for this clean image the same background color cromakey . To merge the two images in the composition of the tracks has been reduced to about one person "bottom" of cromakey much larger than the original size. Just then make the cut through the function cromakey .
cromakey : checking the quality of the backlighting
a way to check if the background is evenly lit is only record a few seconds with this appearing on the display . Next, using a monitor wavelength, which may be hardware type ( waveform monitor , similar to a physical machine to a video monitor which connects the video signal to be analyzed ) or software ( function waveform existing in various programs for non-linear editing , which opens a window with a representation of what would be shown on the actual device screen ) , verify the uniformity of green along the frame of the scene : there should be a straight line in its statement . To prove , in the last seconds of recording test above , ask a person to stand in front of the screen . The indication on the waveform monitor should change right now.
cromakey and adjust lighting the foreground
a tip to make the adjustment of the lighting in the foreground in an assembly of the type which employs cromakey independent illuminations background and foreground , is totally off the backlighting . Next, make all adjustments in foreground lighting through positioning of reflectors , and also their barndoores additional flags . Always keep in mind , during this adjustment , if any of these lights is reaching the bottom - a fact that should not occur .
cromakey and real-time adjustment
a tip for better fit in cromakey is setup to connect the camera output directly to the input of the capture card into a system of non - linear editing on site . So you can , in real time , making all the necessary adjustments and positions between the elements of the foreground , background and spotlights the best condition to be obtained .
cromakey and beat the white
in an assembly to cromakey where a person stands in front of the background that will be cut, adjusting the white should be done excluding the background. To do so , place the card in front of the person and zoom in the camera , the angle close to fully fit the card in the display . Then adjust the white on the camera catching it below. Done catching, return the environment to its original position .
cromakey and distance from the camera to the bottom
a useful measure is to keep the camera at a good distance from the foreground , and so use the zoom in tele position to make the shot. By doing this, the depth of field decreases to a small strip to the front and back of the person in the foreground , failing to reveal any imperfections in the background , once it ceases to be sharply focused .
cromakey and camera movement
recordings of a person in front of a screen cromakey the tip is to avoid as much move the camera . The light settings and positioning of the person has to be accurate , and unless the light set + background is extensive and uniform movement will have an effect of ' esfumaçamento ' ( blur) the image contours , especially if you are using some of the group DV formats .
cromakey and movement of the person
the person who is being recorded on a background for cromakey must move without making sudden movements : these have a tendency to cause a esfumaçamento the image ( blur) which finishes merging with the background, undermining the illusion . The problem is more apparent in formats utlizam lower color resolution in the image , such as the DV format .
cromakey and positioning of the camera relative to the background
the trick is to keep the camera perpendicular to the plane of the bottom . Thus , it should not be too high on the tripod and tilted down or too low and tilted upward . An extreme measure is to check their level of alignment with the aid of a level . On the other hand , lateral angles should also be avoided , the camera should always be facing the screen. In all the above situations , the background will be very slightly closer to one side of the CCD plane than the other, affecting the intensity of light that side - light more intense than the other side. This unequal brightness , depending on the sensitivity setting cromakey can affect the quality of the process , causing some areas do not become fully transparent .
cromakey and foreground glow
the presence of bright objects in the object / person to be trimmed should be avoided , especially when located at the edges of the contours of the same . The brightness at the edges causes the clipping ceases to be a line defined contour relative to the background . The problem can occur for example when cutting an object of stainless steel or a bald person . The trick is to use these objects or people resources to reduce glare - there are specific products for this such as anti -reflective sprays .
cromakey and chalkboard
a school box ( for blackboard chalk) can be improvised as the background for cromakey . The framework must be the green kind , to be with his new and well washed surface free of scratches and flaws , and uniformly illuminated . Herself lighting commonly used at these sites ( fluorescent lights ) can achieve a uniform way the box be used for backlighting ( the box ) .
cromakey and shadows in the background and foreground
if the intention is to integrate the foreground to the background ( a person be " placed " on a beach where it is not for example) , you should pay attention to the lighting of the " background " and foreground , which must be consistent. As " background " here means not cromakey the lighting of the screen itself , but the existing lighting in the place whose image will replace the green screen . Thus , if the sun this beach produces shadows in the trees and others from right to left , in the studio , the person must have the reflector head light also moved to this position . An inversion become inconsistent effect , calling the attention of the viewer for this integration disharmony person / environment.
cromakey and fabrics used in clothing
should be avoided wearing clothes with designs of lines (bands ) very close next to each other . The use of fabrics with these standards entails an effect known as moiree Pattern ( default moiree ) , where these lines are presented with shimmering effects in the image . This effect (which appears even in non- cromakey recordings ) can lead to problems during the cropping of the image especially with the use of digital formats from DV family because scintillations are presented in the form of strange artifacts in the image , these artifacts that carry various colors. Thus, it is possible to have the colors in the input foreground image that correspond to the background , making the parts which are to become -( incorrectly) transparent .
cromakey different temperature and light in the foreground and background
the fund cromakey can be illuminated with totally different foreground in terms of color temperature light if a condition is met: the two illuminations are completely independent . Thus, it is possible for example to employ cold light to illuminate the background and incandescent light to illuminate the foreground : the camera , the beating of the white should be made with light foreground , not the background light . By watching the monitor , after whipping the bottom will get a bluish tint , however this is no problem : simply select this color for the compositing program - and remember not to use it in foreground elements .
cromakey and artificial wind
illusion caused by an effect of cromakey on an external image ( beach, open field for example) can be well emphasized to the viewer if a fan is placed next to the person to be cropped in the foreground . Adjusted for blowing the equivalent of a breeze on the clothes of the person ( the hair cromakey should be fixed preferably with gel) making it vibrate slightly , makes extremely convincing effect. The caution to be taken is to check whether the background image is no wind and which way it blows , to maintain the same direction in the foreground .
cromakey outdoors
You can make pictures of the process of composition utlizando cromakey in outdoor environments , without using a specific screen for chroma . Thus , the background may be the blue sky for example (from a low outlet , bottom-up , which excludes items other than the sky ) . Or walls and facades that have uniform color . The tips are blur the background ( far from the same person ) , possible to hide imperfections like seams of bricks , cracks , etc. ... And use the RGB color matching surface , beyond the yellow.
cloudy days
are excellent for close- ups , especially of people: those days sunlight is not direct, is well diffused because of the clouds . The light rays come from various directions , which makes the shadows cease to be pronounced and areas gain even illumination , causing a pleasing appearance of smoothness .
diffuser screen
when recording scenes of a person talking to the camera directly under sunlight , it can be observed , depending on the intensity of it, and the effect caused by the harsh shadows and high contrast locations on the face of the person . Rather than change the save location for the shade , an efficient solution to the situation is to soften the sunlight , through a diffuser screen . In a very large wooden frame or PVC tubes (preferred for lightness and ease of construction) can mount the diffuser extending over the frame and securing it in the same medium to a screen frame ( voile for example) tissue . Screens in black work best . At a distance of about 2 to 3m of the person for example, the diffuser is suspended so as to cause a 'shadow' on the person actually an attenuation of strong and hard ( light that causes well-contrasted shadows ) sunlight.
dimmer for controlling the light intensity
in situations where basic light kits of the consumer or even semi- professional type are used , an alternative to smooth or reduce the intensity of light is common to use a dimmer . Can be constructed a device consisting of a box in which , on one of its surfaces , control of the dimmer with the unit is installed inside . Leave the device input and output cables , fitted with male / female plugs on the ends . It is essential that the whole construction is made with heat resistant materials , flame retardant yarn (which is now currently a standard cable industry ) , plugs first line and that all connections are correctly mounted , wireless or screws not well established . This procedure must be followed naturally in all types of electrical installation . The other point to note is that the dimmers are manufactured to work with a certain capacity threshold ( wattage ) . Thus, the sum of the power of the lamps connected to it must be less than this capacity. Finally , note that not all bulbs are dimmable , especially those of common fluorescent type . Met these observations , one can have a handy device , handy for when you need to reduce the intensity of light without resorting to filters placed in the spotlight . As a final note , remember that the reducing power of the lights will need to make the adjustment of white again ( if not already done and if the goal is to produce a display with true color to reality ) .
disguising skin problems
to disguise , in the image , excessive wrinkles and / or imperfections in skin texture , the trick is to soften the lighting. As these imperfections constitute irregularities in the surface relief of the skin , the light it receives may be partially blocked in several passages , creating tiny shadows that accentuate the contrast between the flatter parts . One can compare the effect to a flat and smooth terrain, which does not produce shadows when lit by the sun and full of ups and downs in the terrain relief . These ups and downs produce shadows when light hits them at a flat angle . These shadows more than the actual irregularity of the relief, mean that there is a sharp contrast between light and dark parts . In other words, if there were no shadows , the image would be more uniform and smooth. In very small scale is what happens on the surface of the skin . So all you can do is try to reduce these shadows . For this, some alternatives can be attempted. One is to avoid side lighting , giving preference to the front lighting of the face ( equivalent to Sun noon in contrast to the beginning or end of the day ) . Another use soft light , no light " lasts " : There smoothing gels that can be used on reflectors , or soft boxes called softbox , always arranged frontally . Another way out is the use of a smoothing filter on the camera lens or still a smoothing effect in the post - editing - applied with little intensity.
avoiding duplicate shadows
in an assembly with reflectors to illuminate a person standing next to a wall background, runs the risk of the spotlight produce different shadows on this background, a result that may have amateurish aspect or agitated then remember interviews where several stations TV position their equipment while promptly to capture some statement of the respondent. If two reflectors for example , it is acceptable that the shadow of one of them is projected on the wall , but not both. In this case , simply position of the reflectors directly facing the person's face - but located laterally to it - without caring about the shadow that forms the background. This will be the main light in a main / fill scheme . The second reflector ( field) should be placed on the other side , preventing its light reaches the bottom , or through its rotation turned slightly away from it, or via a flag ( opaque reflector plate placed next to the spreads its light ) . Placed farther from the face of the person , allow the creation of a softer light , thus causing the highlight of the three-dimensional aspect of the face.
excess light
ND filter and contrary to what one might imagine , the more light is not always best : in this situation , the bright colors begin to become saturated and the image lacks in definition . To circumvent this problem , common in very bright environments ( beach, snow for example) a filter type ND ( Neutral Density ) can be added to the camera lens. This type of filter , which exists in various degrees , does not change the colors of the recorded image , only reduces the intensity of light that reaches the camera lens , allowing better exposure of the subject .
fixing reflectors in doors
a door can be used in emergency situations where there is no traditional supports available to fix a reflector . The idea is to use clamps with powerful springs , coated with rubber or plastic material ( found at hardware stores ) . The clamp is fixed at the top of a door, must be set slightly open - both use a pad underneath it. The clamp via a tight and secure fit is used to hold the reflector at the top of the door. Other locations may also be used for fixation .
fluorescent
can be used without problem as artificial light source , since it Take care to make up the balance in color temperatures that illuminate the person / object. If only fluorescent lights are used , use the automatic white -balance the camera
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