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11 votes
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Digital cameras see black scrolling lines when filming light from my desk lamp

Cheap (to make) LED lights will flicker at twice the mains frequency. There are many ways of overcoming this in the design of lights, such as using a larger smoothing capacitor (which makes the light ...
Pete Kirkham's user avatar
9 votes

Digital cameras see black scrolling lines when filming light from my desk lamp

The reason is very simple. LED's are not constantly turned on, but flicker at a very high rate, usually due to fluctuations in your powerline. Your video camera records at a fixed framerate and as ...
LPChip's user avatar
  • 191
7 votes
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SDI - serial digital interface

General SDI vs. HDMI Information SDI is easier to connect to other professional equipment than HDMI. It is an all purpose signal, as opposed to HDMI that was originally intended only to connect to ...
Michael Liebman's user avatar
5 votes

What are Grey Balls used for?

Yes, they are used for adding visual effects in post. The mirrored ball is for creating an environment map or reflection map. These maps provide the same lighting from the real scene to the virtual ...
user1118321's user avatar
  • 2,156
4 votes
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Why use different camera angles?

Different angles are used for many reasons. Wide and/or long shots are used to establish the setting where the video is being shot. Medium shots are used to show the relationship between people and/...
Richard Crowley's user avatar
4 votes

What is causing these horizontal lines moving vertically up the whiter portions of the video?

You seem to have a flickering light source that is out of sync with the camera's rolling shutter. Traditional lights You should first verify that you are filming in 60/30/24 fps in regions whose power ...
Duvrai's user avatar
  • 803
4 votes

Digital cameras see black scrolling lines when filming light from my desk lamp

LEDs are a very fast reacting light source, far faster reacting than incandescents or even flouresecents. So if the current through the LED varies rapidly the light output will vary equally rapidly. ...
Peter Green's user avatar
4 votes
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Camera flash produces unwanted artifacts on the video

This is actually a collateral effect of the concept of rolling shutter. Most video devices do not expose all the frame area at once. They expose starting from one side and (up or down) and move from ...
Rafael's user avatar
  • 1,202
4 votes

What is the minimum camera requirements to create professional quality videos?

The camera only plays a part in what makes a good, clean image. The most important parts are Lighting, Lenses and Knowledge of the person operating the camera. If you film in a dark location and have ...
Florian Claaßen's user avatar
3 votes
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How do I replace my organisation's event video camera?

Firstly, that camera has a 29 minute 59 second recording limit. If your speaker goes for longer than this it may not be suitable. Apparently this is due to some countries charging higher import duties ...
stib's user avatar
  • 13.8k
3 votes
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How to record HDMI video with USB?

You already stated your options and you only have one that would work: you need a frame grabber. A frame grabber is a specialized chipset that does a very specific task. Sometimes such devices are ...
user3643's user avatar
  • 2,306
3 votes
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How to get the Cinematic look

There are a few important things to consider: Lighting is perhaps the most important aspect to creating a filmic image. A lot of filmmakers like to use natural light such as Innaritu on The Revenant. ...
Alex's user avatar
  • 809
3 votes
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What are Grey Balls used for?

The grey balls are actually used like the grey cards but with added lighting data cause they are spherical and refer to the surrounding light sources better, they usually reflect 18% of the light and ...
Reuben Tilahun's user avatar
3 votes

How does shutter speed affect the video?

A high shutter speed can make individual frames look more crisp but make large motion look like it is stuttering. e.g. fast panning looks like it is flickering or jumping A low shutter speed can make ...
GiddyUpHorsey's user avatar
3 votes
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How does an optical viewfinder on a film camera work?

There are three ways that film cameras do this: Using a rangefinder, i.e. a viewfinder that doesn't actually view through the lens. Common on cheaper consumer format cameras such as super-8 Using a ...
stib's user avatar
  • 13.8k
3 votes
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How to realistically add planet in the sky using 3d camera tracker and avoid overlapping with objects in the foreground?

If the blades are rotating, and the camera is moving, you need to create a good foreground layer with anything the planet is supposed to be obscured by. So from the image it looks like it will be ...
tomh's user avatar
  • 8,137
3 votes

Best hidden camera rig techniques

I've been on guerrilla shoots where they had a GoPro peeking through an O on a protest sign, held at head height like the protester isn't actually protesting right this minute. Also, I've seen a ...
Tetsujin's user avatar
  • 616
2 votes

What is good software for camera recording under Linux?

OBS (Open Broadcaster Software) is multi-platform (OBS is widely used in video game streaming). I haven't tried it yet myself for multiple cameras, but I know it supports at least one (as many ...
Xavier's user avatar
  • 21
2 votes

BMPCC + rafcamera arri b to mft + optar 1.2/12mm = vignetting

I'm not familiar with the setup you described, but does that adapter have some sort of iris control built into it? I have the adapter pictured below and it doesn't allow the BMPCC to adjust the ...
Manly's user avatar
  • 290
2 votes
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how can we shoot tv show so "tarak mehta ka ulta chasma" it will look like "house of card"?

I see four basic differences (in what I believe is the correct priority order): Lighting. The lighting on Kevin Spacey is classic three-point lighting with warm fronts, a 2:1 key/fill ratio, and ...
Michael Tiemann's user avatar
2 votes

Reference Request: Camera Movements

Mic shot looks like a dolly back tilt to track the subject. This is a compound movement that is natural to do with a hand held camera but more challenging when using a digital camera. Try tracking ...
3pointedit's user avatar
2 votes
Accepted

Camcorder vs. not a camcorder and separate audio and video recording

Terminology In theory, a camcorder is a video camera that also records video. A long time ago, this was an important distinction, since movie cameras (which are analog and record to film) and other ...
MoritzLost's user avatar
  • 5,442
2 votes
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Will Canon lens work with a7s II?

Ah yes, Canon lenses are a lot cheaper it seems than Sony lenses. With the A7s ii you an use both APS-C and FF (full frame) lenses. With an APS-C lens you have to enable APS-C mode in the camera and ...
Alex's user avatar
  • 809
2 votes

GoPro Hero 5 Session camera for long shot (crowd shot)

Yes, useful for wide crowd shots. Yes, you can crop down/scale up 1080p selections from the 4K to simulate additional camera angles. Consider using the gopro app or a wifi remote to stop/start the ...
alexh's user avatar
  • 703
2 votes
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How to create a pseudo 3D/virtual POV effect

Th general technique is called camera mapping, projection mapping, or videogrammetry. It works by taking a photo or video from an angle and projecting the image onto geometry. As a simple example, ...
user1118321's user avatar
  • 2,156
2 votes
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How to capture documentary quality footage of tiny subjects

Up until the high-frame rate (HFR) section of the video I would have said that all you need is a Canon MP-E 65mm Macro Lens, a nice LED light (so as not to fry the poor bugs with all the IR radiation ...
Michael Tiemann's user avatar
2 votes

SDI - serial digital interface

In short; HD-SDI and SDI are the industry standard for professional applications; and HDMI is for consumers. HDMI is highly limited in terms of length; you will need a very high quality cable to go ...
McFlySoHigh's user avatar
  • 2,487
2 votes

SDI - serial digital interface

SDI is a professional, locking video connection system over coax cable. SDI itself has more expensive licensing costs associated with it than HDMI, so hardware that supports it will generally be more ...
AJ Henderson's user avatar
  • 19.4k
2 votes

360-degree cameras and the sun

Your initial assumption about damage risk is a little too general. I have taken thousands of photos, and a lot of video, having the sun within the sensor's image. No damage, and for good reason. ...
MrPete's user avatar
  • 21

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