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Old 08-10-2012, 03:29 PM
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alocky (Andrew lockwood)
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Avoiding flicker in time lapse movies with a D800?

Hi all,
I just picked up a secondhand 14-24mm lens, having hired one previously and been suitably impressed. This weekend I plan to give it a workout.
When I've tried time lapse movies with the D800 through sunset, I noticed the automatic iso occasionally jumps too far and the resulting movie has a flickering background. Can anyone share their tricks for reducing this?
Cheers,
Andrew.
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Old 08-10-2012, 03:47 PM
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pluto (Hugh)
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Hi Andrew,
I think that when using auto ISO you'll always get flicker. You could try using a variable ND filter and adjust it as the sun rises (or sets) but you'll probably still get flicker.
I think you'll need to fix it in post. We've used deflicker plugins for Nuke, After FX etc at work but if you don't already have a compositing package that could be quite an expensive route.
A bit of googleing led me to this: http://www.granitebaysoftware.com/pr...roductgbd.aspx - It is standalone for windows and it has a trial so could be the way to go.
This also looked interesting: http://lrtimelapse.com/ - a plugin for lightroom.

Oh and you have of course set a manual white balance? I've forgotten that on a couple of occasions and it can add a nasty flicker.
Good luck!
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Old 08-10-2012, 03:49 PM
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alocky (Andrew lockwood)
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Excellent tips- thanks. I didn't know about the white balance either.
Cheers,
Andrew
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Old 08-10-2012, 09:04 PM
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Check out LR timelapse, it should be able to sort you flicker out.
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Old 09-10-2012, 10:50 AM
Poita (Peter)
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I set manual everything for timelapse and do not get flicker problems.
Manual exposure, fixed ISO setting and manual whitebalance.
For time-lapse or for panoramas you want to have consistent settings from frame to frame to get solid results.
Shoot in raw and you have enough leeway for correction later if you want to adjust exposure as the sunset progresses.
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Old 09-10-2012, 10:51 AM
Danack (Dan Ackroyd)
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Quote:
Originally Posted by alocky View Post
I noticed the automatic iso occasionally jumps too far and the resulting movie has a flickering background.
That's weird. The camera's exposure should be pretty much the same - having the ISO change shouldn't make the background flicker, it would only make the picture have slightly more/less noise.

Can you say exactly what settings you're using and maybe post an example video to Youtube?

If it is the auto that's causing the problem and if you're taking full sized photos to turn them into a time lapse, you could just set the camera to ISO 800 and not worry about it. By the time you've reduced the photos to video resolution, any noise from using that iso instead of 100 will be pretty much invisible.

Quote:
Originally Posted by pluto
Oh and you have of course set a manual white balance?
I don't believe that is necessary. The white balance shouldn't be changing that much between frames, but can change dramatically over a sequence of shots (e.g. http://www.youtube.com/watch?v=YLh8pag7DH4 ) and so need to be left to auto-white balance.
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Old 09-10-2012, 10:51 AM
Poita (Peter)
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Quote:
Originally Posted by pluto View Post
Hi Andrew,
I think that when using auto ISO you'll always get flicker. You could try using a variable ND filter and adjust it as the sun rises (or sets) but you'll probably still get flicker.
I think you'll need to fix it in post. We've used deflicker plugins for Nuke, After FX etc at work but if you don't already have a compositing package that could be quite an expensive route.
BTW, where do you work?
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Old 09-10-2012, 04:03 PM
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You can try shooting aperture priority mode as well as auto ISO. I think also there is a menu step where you can program the minimum ISO steps. Make sure that is set to the lowest step.

Also when setting auto ISO don't forget it also asks for minimum shutter speed so set that thoughfully. Too high and it will give the camera a problem when it gets dimmer. Too long and it will overexpose before sunset. So you set the aperture to suit.

I have done a sunset to dark time lapse with D800E and it was relatively smooth. There is also a deflicker plug in from Granite Bay Software. Not sure if it works with Nikon and jpegs. You'd have to check their site. It works in Lightroom.

Greg.
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Old 09-10-2012, 04:52 PM
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Quote:
Originally Posted by Danack View Post
That's weird. The camera's exposure should be pretty much the same - having the ISO change shouldn't make the background flicker, it would only make the picture have slightly more/less noise.

...

I don't believe that is necessary. The white balance shouldn't be changing that much between frames, but can change dramatically over a sequence of shots (e.g. http://www.youtube.com/watch?v=YLh8pag7DH4 ) and so need to be left to auto-white balance.
The flicker from auto ISO would be because the ISO is changing in relatively large increments, like 200 to 320 (maybe you can choose smaller increments depending on the camera) so if aperture and exposure are locked off then there will be a noticeable jump in brightness.

I only mentioned the white balance thing because I have seen it on timelapses I have done where everything (exposure time, aperature and ISO speed) is locked off and I have forgotten to set a manual white balance. A couple of times I have remembered mid shooting and set the white balance and seen afterwards that the flickering stopped at the point I set the WB.

Poita: I'm a 3D/VFX artist at a company called Collider in Sydney.
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Old 09-10-2012, 05:37 PM
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If you want, have a look around at Bulb Ramping this will once set right will gradually set your cameras exposure time, and aperture etc... so it will gradually change at the light fades or increases during the time of the exposure. If you look for Little Bramper this little device could help you out.
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Old 09-10-2012, 08:32 PM
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Poita: I'm a 3D/VFX artist at a company called Collider in Sydney.
Ah... I used to work at Animal doing much the same thing.
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Old 11-10-2012, 04:02 PM
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[QUOTE=pluto;902784]The flicker from auto ISO would be because the ISO is changing in relatively large increments, like 200 to 320 (maybe you can choose smaller increments depending on the camera) so if aperture and exposure are locked off then there will be a noticeable jump in brightness.

I only mentioned the white balance thing because I have seen it on timelapses I have done where everything (exposure time, aperature and ISO speed) is locked off and I have forgotten to set a manual white balance. A couple of times I have remembered mid shooting and set the white balance and seen afterwards that the flickering stopped at the point I set the WB.



Good tip.

D800 can be adjusted for ISO steps to be either 1/3rd 1.2 or 1 step. Chose 1/3rd.

Also try aperture priority as that will also change shutter speed to suit the metered scene so you have 2 variables going instead of 1.

Greg.
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Old 11-10-2012, 05:21 PM
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Moon (James)
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You could also try the MSU Deflicker filter with the 32bit version of virtualdub.
Works ok for me.
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Old 12-10-2012, 03:29 AM
Danack (Dan Ackroyd)
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Quote:
Originally Posted by pluto View Post
This also looked interesting: http://lrtimelapse.com/ - a plugin for lightroom.
That's a really nice tool. There's a couple of things that I didn't know about on the forums there.

http://forum.lrtimelapse.com/Thread-...-lens-related:
Quote:
when the camera sets the aperture "electronically" it submits the distance the aperture lever should be moved to the motor that moves the lever, this is not as accurate as you would like it to be when shooting timelapse. A fraction of a micrometer difference leads to a change of the diameter the aperture opens. That's the reason why many photographers use lenses with aperture rings, shoot wide open or use tricks like described above when shooting time lapses.
Also, apparently some cameras have trouble with keeping very fast shutter speeds consistent (e.g. 1/6400s) and so you should use ND filters to avoid those high shutter speeds.
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