Setting Up a Shot

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All of these settings can be set to 'AUTO'. If you're in a rush then 'AUTO' will usually give okay results. On the big black HD cameras, lightly press the 'menu' button on the screen, this will allow you to change the common settings. If one of the settings has a yellow/orange bar next to it then it's been set to manual and you ought to check that it's been set appropriately.


Exposure

This determines how bright the image is. It is done by controlling 'Shutter Speed' and 'Iris' (referred to as 'aperture' in still photography).

Shutter speed / angle, is the amount of time that each frame of the footage is exposed to the light entering through the lens. As a speed, it measures the physical time in divisions of a second that the frame is exposed for. This will be familiar to those who have used stills cameras before.

As an angle, it actually describes a piece of vintage photography from the genesis of film making. The shutter for a motion picture camera was controlled by a number of spinning disks with wedge cutouts in them allowing light through to expose onto the film. The angle of these cutouts determined the effective shutter speed of the camera. On modern cameras of course, this is all digitally controlled and can be set to the nearest 15 degrees (from 15 to 360).

YSTV almost always uses a shutter speed of 1/50th of a second, or 180 degrees if using shutter angle. This is because it is usual to broadcast at 25fps (which YSTV also does) and the normal shutter speed for shooting is to shoot at a shutter speed of twice the frame rate. I.e. so that each frame of the footage is exposed for half of it's interval. This results (at 25fps) in a shutter speed of 1/50th or 180 degrees (which would expose the film frame for half of its time as it passed through he plane.

180 degrees (1/50th) is a good rule of thumb for ~80% of content. There are situations where changing the shutter speed to ~1/60th is advisable:

  • You're filming something that moves really fast and want the footage to blur less. If the view is still light enough after increasing the speed, go for it.
  • To stop on-screen monitors flickering, increase the shutter speed to 1/60th. (Computer video pretty much always draws at 60Hz.) If the shutter speed is not on the main menu; you have to enter the detailed menu to alter it. See the camera operation documentation or see production or technical people.
  • Filming on a green screen, shooting at a faster shutter speed reduces motion blur and so make s the key cleaner and faster

Alternately, raising the shutter angle to ~300 or so works very well for a dream sequence or other artistic effects where a lot of blur is desirable.

The iris is a physical barrier inside the camera which can be opened or closed (by internal motors) to change the amount of light that actually enters the lens and thus arrives at the shutter. In most lenses they are formed from at least 6 blades which expand and contract to increase or constrict the size of the central hole which allows light to pass.

Everybody has their own rules for ideal aperture settings and the effect intended will also influence the aperture setting of choice. Also, some lenses have a range of minimum aperture across their zoom or have aperture.

The general effects are:

  • Lower F stop numbers (the term used to represent the current aperture) cause more Bokeh (blurry background past the point of focus) and a smaller depth of field (depth of the area in focus on the subject). Higher F stop numbers have the opposite effect.
  • Lower F stop numbers introduce more light into the image, bigger central hole so more light, and higher F stop the reverse.

White Balance

When filming in light that isn't evenly white (ie it has a tinge of a certain colour) the camera needs to be told what it should consider truly white. If the white balance is set to auto, and the camera is, for example, used indoors where the light normally has an orange tinge, the camera will assess the entire image, determine that orange is the dominant colour, and reduce the amount of red in the recording.

'Auto' will usually produce useable results, or at least ones which can be improved later in editing, however it is best and easiest to set it manually when the recording is taking place.

Use the camera guides to see specific information for setting white balance on our cameras, the menu system is not the same for all of them. When setting the true white reference, fill the entire frame with a white reference card. A white light bounce or diffuse will work, if one is not available then you can use white card or paper.

Focus

Focus on the camera can work in one of two ways; Auto and Manual. Manual involves telling the camera how far away from the lens your subject is, and that's what it'll focus on. Auto involves the camera looking at your footage and working out by itself how far away your subject is.

If you're filming in decent light and frequently changing zoom and/or composition, then Auto is advised. Another good use case for auto is when the shot is not setup (a report for example). When it is required to get the shots and things are unpredictable then the auto focus is the best thing to use, it might not be 100% accurate, but its way more reliable than trying to constantly focus pull on manual.

There are, however, many cases where manual focus is the right (or the nicer) option to use. These can be in well setup and rehearsed shots (especially with a focus puller) where a smooth focus pull from one subject to another can be done very smoothly and make the shot better for it being on manual. Also useful, is manual focus when the subject is not centre frame. Often., auto focus systems require the subject to remain central in the frame in order for the system to work as intended. When the blocking causes this not to be the case, manual can make the shot a lot nicer.

On the C100s the auto focus is on the lens and is a small switch or similar between AF and MF. Note, changing this mid shot does tend to introduce a slight wobble to the shot. The C100s also contain 1 shot AF and AF lock (only on the MK2 version) which allow for smoother transition between MF and AF. The focus ring is on the lenses and varies is smoothness and size depending on the lens.

The AGAC90s have a focus ring on the lens in the same way, and the selection switch is on the control side of the camera. Normally these are used in auto focus mode only.

Microphone & Sound Levels

The short answer: set everything to Auto. As long as its not clipping, its fine for most things. The long answer (for good results): More on sound setup