twist

Getting rid of flicker in timelapse – The Lens Twist Method by Dustin Farrell

by Dustin Farrell14 Comments

We’ve got another new writer (as we promised a few weeks ago) – Dustin Farrell is going to be contributing to planet5D about what he’s learned doing timelapses (remember the “Landscapes Volume 2” post?) If not, you should go watch that to see how amazing Dustin is! We’re thrilled to have him contributing to planet5D!

Dustin on the Twist

On almost a daily basis I get an email asking for help on how to shoot better time lapse. The most common question that I get is how to get rid of flicker. Turning all of your DSLR settings like exposure, white balance, and focus to manual will eliminate most flicker. If you are shooting time lapse in all manual modes and still having problems, you’ve probably got a case of “aperture flicker”. This type of flicker is caused by a DSLR’s inability to open and close the aperture blades of a lens the exact same amount every time.

There is a lot of literature online that suggests shooting wide open to eliminate this problem. Shooting wide open eliminates the closing down of your aperture and in theory should eliminate aperture flicker. In most cases it does. However, you now have created two possible problems. First, since you are now shooting wide open, there is a chance that you have increased your shutter speed tremendously to be able to expose correctly. Believe it or not, very fast shutter speeds can also cause flicker. By eliminating one DSLR inaccuracy you have created another. It is hard for a DSLR to open and close a fast shutter at the exact same speed every time. If this problem sounds familiar to you, use some neutral density filters and/or a lower ISO so that you can slow down your shutter speeds.

The next problem created by shooting wide open is that it usually doesn’t result in the best picture quality. Even the best lenses become soft on the edges when you are shooting wide open. Often the “sweet spot” of a lens is found two to four stops from wide open. I try to never shoot with the aperture all the way open with wide lenses and this is why I prefer the lens twist method.

How to lens twist: While holding down the depth of field preview button (DOF Preview) press the lens release button (picture 1).

Picture 1

The aperture blades will be closed down to your selected aperture (picture 2).

Picture 2

Now while holding down both buttons twist the lens as if you were removing it. The twist should be a very small turn. You should now see a “00” where your aperture information used to be (picture 3).

Picture 3

A great way to test the amount of twist is to put your camera in its live view mode before twisting. As soon as the camera has lost contact with the lens you will hear the mirror return to stills mode. This is a good thing because the camera is no longer talking to the lens and cannot create aperture flicker.

Now that you have executed the lens twist you must perform a quick test. Every camera body and lens combination requires its own perfect twist. To test to see if you have twisted just enough simply take a picture. If you have done this correctly, besides the “00” aperture reading, the camera will act normal. If you haven’t you will get an error message like the one in (picture 4).

Picture 4

Re-attach the lens and try again. Some lens and camera body combinations are difficult to get just right. Take a few pictures to make sure you do not get an error.

The only negative to the lens twist method is that the camera will not be able to record the lens information to each picture taken. However, as long as you remember what lens you used for the time lapse, most software will allow you to manually enter a photo’s lens information. Nearly every shot in “Landscapes Volume 2” was done with a twisted lens.

Dustin on Twitter

Company Website

Dustin’s demo video

(cover photo credit: snap from the video)



11 comments
Atreidae
Atreidae

This trick also works even if you don't have a DOF preview button (a feature I miss from my D70s on my newer d3100 body) Jump into shutter priority or stick a bulb trigger on. Set the exposure as desired. Start exposing. Press the lens release and Twist You may need to turn your camera off and on again to get the mirror to return (I imagine this will be rare)

Darin
Darin

I realize this is almost a year old, but this was very helpful! Thanks a lot! :)

Tony Anastasi
Tony Anastasi

Does this only happens on canon cameras or nikons and the rest of them also ?

Kim Brun
Kim Brun

I too use manual lenses to eliminate flicker. I am currently using my older Nikkor lenses on my Canon 5D via a couple of adapters. I am also using my Hasselblad lenses, via adapter, on my 5D. With the Hassie lenses I was expecting a higher quality image do to the much larger coverage and only using the "sweet spot" of the lens. But with both groups of lenses, these pre-digital designs have some color aberration issues on the edges. Easy fix in ACR. I do like the softer contrast though. My concern with the lens turning, maybe unfounded, would be creating electronic issues if the contacts were in partial contact.

Odd Geir Sæther
Odd Geir Sæther

The described problem is - of course - nonexistent if you happen to be using Nikon lenses - either the older type of lenses with a diaph ring. or - G lenses with the special adapter which allows for a control of the setting (Novoflex)

Jake
Jake

Or just use a manual lens?

Dustin Farrell
Dustin Farrell

LRTimelapse is a fantastic timelapse tool for many purposes. However, flicker is always difficult to eliminate perfectly in post. For Canons, the lens twist method eliminates aperture flicker perfectly and edit time is reduced.

Kim Brun
Kim Brun

Tony - It is a problem with all auto exposure cameras. The lenses do not always give the same exposure from shot to shot. The iris or aperture will vary slightly overtime and give you a flicker when turned into a time lapse sequence. That is why manual lenses do not present a problem. The aperture on a manual lens is already stopped down and therefore doesn't vary over time and thus no flicker. Hope this helps.

Dustin Farrell
Dustin Farrell

Yes. Most of us no longer have manual aperture lenses. If you do aperture flicker will be of no concern to you.

Ales
Ales

So I have to try it! But there is one think that I'm afraid of. The lens is not tightly lock in the body mount, isn't there a problem with stability? Does the body can hold sufficiently? Or what about the backlight that could come to the sensor by the chink that appears between body and lens? Thanks.

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