In a nutshell what is HDR video ? 

HDR (High Dynamic Range) is a technique that first started in photography, essentially taking an under- and over-exposed photo and putting the two images together to create an image with higher dynamic range than the camera can capture in one image.   To do this in video is essentially the same technique, creating a very colourful image using a much wider colour spectrum.  This presents one with an image, closer to what the human eye sees as opposed to normal video.  One thing to keep in mind about HDR is that is a relatively new technique so there are a few limitations at the present moment.   The main one being that most televisions and displays actually can’t show the full colour spectrum that HDR captures.  Another limitation is that with moving images an effect known as ghosting (the layering of multiple images) can occur, distorting your video.

What specialist equipment, expertise or processes are involved ?

There are a few different ways of achieving HDR video, which involve different types of equipment.  At the lower end of the scale on certain DSLR cameras you can use a firmware called magic lantern which has a HDR function on it.  This sets two ISO values; one low and one high; then swaps from frame to frame between the two values for the different exposures. But that isn’t the end for this workflow.  You then have a lot to do in post-production stitching the two images together, using further software.

Man sits at computer desk graphic.

A lot of mid range cameras now allow you to film in log which flattens the image so you can achieve HDR by the colour grade in post.

At the higher end of the scale, cameras like the Red have a system called HDRX which uses shutter speed to achieve the different exposures. It works by by creating two video streams in the same file called A frame and X frame which can be used separately or together to create HDR video. There is still a bit of post production workflow to be done with this but not nearly as much as the the magic lantern technique. You basically have access to both video streams and can then blend them together to get the perfectly exposed shot.

Why should I consider using HDR video in my production

The best uses for HDR video at the moment occur when there is a drastic exposure changes in your image.  For example, a scene set inside a room with a large window, where is is important for the viewer to clearly see the interior and the exterior, areas with dramatically different amounts of light.  Alternatively, it can be used to create a dreamlike look for a music video or experimental moment in a feature.

The best corporate use for this technique would be in real estate style videos, where the aim is to demonstrate the beauty of the inside and the outside of the property in the same shot.

When wouldn’t HDR video be ideal for my video production?

Owing to the motion blur issues and ghosting  that occurs with rapid movement, the technique becomes unnecessary for any video featuring a subject moving quickly.  Also, at the present time, while standard technology catches up with HDR, combined with the extended post-production work needed, HDR should only be used if you have a definite desire for it.

In Summary

HDR video is a new and exciting filming technique but unfortunately it is another one where the camera technology has surpassed the display technology.  Though it can be used to great effect for shots requiring difference in exposure, we are forced to wait for the display technology to improve before we see it’s full potential realised.

Useful Links 

Tubular Insights

HDR on Wikipedia