Discontinuous light sources = "banding" for Nikon D90 LiveView recordings

[Ralph Oshiro]

[NOTE: Okay, so this isn't a "new" issue, but I had originally searched the forum for the terms "flourescent," and "banding," but I didn't find any relevant information in the resulting posts. Also, I didn't realize people were using the term "banding" to describe a completely different artifact, and I also wasn't aware that people are referring to this artifact as, "scrolling waves."]

When shooting in LiveView with the Nikon D90 under discontinous light sources, "banding," or so-called, "scrolling waves," (sometimes referred to as 60Hz roll bars) occur in the recorded LiveView imagery. This issue is discussed in the "Nikon Europe Official Response" thread, but I thought a more appropriate thread title could help others find this information, here, more easily. Note that this limitation in the D90's design makes shooting in circumstances where the primary light source is florescent UNUSABLE (see workaround below). If the workaround is unsuccessful, footage captured under these conditions are, in fact, unusable. This issue is specifically mentioned in the user manual, as someone had pointed out previously. Other discontinuous light sources mentioned in the Nikon D90 manual:

1. Florescent (flourescent).
2. Mercury vapor.
3. Sodium vapor.

Since my entire house is lamped with florescent strip lighting, this artifact of the D90's rolling shutter was clearly and immediately apparent. The footage is completely unusable, exhibiting large bands across the frame. The effect is most exaggerated under very low light levels (1-5 footcandles), and appears to attenuate under greater light levels. I just tried exposing some night exteriors under sodium-vapor street lighting, and because 90% of the frame was dark (or the output of the lamp was so low), the banding wasn't noticeable. I also own a two-bank, standard KinoFlo, but I haven't yet tried using it with the D90. Apparently, LEDs are "more" continuous than standard florescent strip lights since I haven't observed this problem using some under-cabinet type, LED "striplights" I purchased at Ikea.

As others have mentioned, adjusting the shutter speed to the exact frequency (or multiple thereof) of the discontinuous lighting source, could eliminate this effect. In the US, this would mean a 1/60th or 1/120th of a second, available shutter speed. Again, as others have mentioned, Nikon would have to update its firmware to allow manual adjustment of shutter speed for this to be an option.

[Ralph Oshiro]

After searching through these threads one more time, I did find a helpful thread with a workaround, although, I accidentally closed the window and now don't remember where the thread was or what it was titled. The same TS that began the "Nikon Europe" thread offered this workaround:

Flourescent "banding" workaround:

In LV mode, with AE-L set to "lock" in the custom settings menu (see kholi's sticky), pan around your scene while engaging and disengaging your AE-L. The idea is the "catch" the camera while it is setting its shutter to a flicker-free rate (i.e., 60Hz). I tried it, and with some effort, it works!

[Martin Landsburg]

It was mentioned somewhere in a thread before. Someone had said to move over a midtone and it might stop banding, then instantly lock with AE-L. Basically keep moving the center of the frame over a midtone and eventually it will lock (sometimes works in brighter areas too).
It can get down to 30% banding, or 50% or nothing at all, just keep paying attention to make sure of a total drop in banding before you start shooting.

it is a workaround but still not always bulletproof...

[Ralph Oshiro]

Someone had said to move over a midtone and it might stop banding, then instantly lock with AE-L. Basically keep moving the center of the frame over a midtone and eventually it will lock (sometimes works in brighter areas too). It can get down to 30% banding, or 50% or nothing at all, just keep paying attention to make sure of a total drop in banding before you start shooting.

Yes, I read that, too, and that did work as well. However, my resulting AE-L exposure was too dark using that method.

[mattsand]

then aim it at something darker, or use the +/- adjustment. no method works if you're not doing it right. :-)

/matt

[Ralph Oshiro]

then aim it at something darker, or use the +/- adjustment. no method works if you're not doing it right. :-)

/matt

Well, I'm using strictly the AE-L lock to lock-up my exposure. I've been doing my AE-L lock-up on the fly with good results. I think I've resolved to change all my lighting to LED and luminescent panels. Gonna buy a bunch of those new Rosco LitePads as soon as they start shipping. Haven't dragged out my KinoFlo yet to see if that exhibits any banding.