Time Lapse help Day into Night

B

bobhope

Well-known member
So...as the title suggests, I've been racking my brain trying to come up with a way to smoothly adjust the exposure of the HVX over time while shooting some landscape timelapse stuff.

Shooting 2 fps, 350D. Shutter. I typically start around an hour before sunset and finish after the sky has become totally black, but still lots of light pollution from LA. I really want to capture the dusk into night appearance.

The footage so far looks good, but I start out with ND filter 1/64, and end with ND Off and open at 2.8. It might be possible to manually adjust the iris smoothly, like doing one stop every 10 minutes or so, but when I click off the ND filters, it really spikes the exposire. So, naturally, during playback, its a jarring effect of seeing everthing get lighter.

Any suggestions?
 
I don't believe there's lanc control of the iris for the panny, but I'd check - if so you could hack a box which would step down the iris for you :)

otherwise, just sit there and roll the wheel by hand ;)
 
On 35mm there are typically 2 ways of doing it - using a spot meter rigged to a norris intervolometer (do a google on it) or, expose and meter for sunset, then on second take expose for night & disolve the 2 in post. On 35mm I've had the most consistently pleasing results with the later, even on a motion control rig where the movement is completely replicated. Good luck.
 
I have found no smooth way to adjust iris--you could set it to automatic, but that doesn't help with the ND. In any case, the iris adjustment looks very sudden and harsh in timelapse--manual or automatic.

I like planetearth's suggestion, but for the difference in appearence of the sky in the two takes. How do you handle that when you've done it? (Clouds are worse than actors when it comes to hitting their marks consistently.)
 
Anyway you slice it there will be a compromise with using that combination of FPS and shutter speed.

If you're flexible with your settings you have options that don't involve using the ND.

Test underexposure by 1-stop, screw on an ND3, and correct in post. Might work out fine.

I.
 
[SIZE=+0]I would try leaving the exposure set even with the ND maybe with a little overexposure; 1/4 to 1/2. The theory being that when the exposure gets dark enough the camera will make it night time. This may not apply to a sunset transition into a night street shot but may work combined with planetearth's application of dissolving the tow shots.[/SIZE]

[SIZE=+0]Also, I agree with Illya in using external ND filtration. I suggest a matte box with filter trays and a full set of filters, 3,6,9,1.2, for ease of use and only a one stop difference between changes. The trick is to match the exposure when you change filters. Use the zebra for that; on something that is constant.[/SIZE]

[SIZE=+0]David[/SIZE]

P.S. Why does spell check increase the size of my font?!!!
 
mcshyd,

Jeff's right. Auto exposure will most likely introduce more exposure changes than desirable. When sped up I prefer to see natural exposure changes i.e. clouds shadows. When I've used auto, the changes have looked erratic, caused by movement in the frame. I wasnt going for erratic in my time lapse. Also, the auto exposure kept the light level constant too long into dusk and only a transition into night when the aperture reached wide open. The bottom line is I didn't like the result.

Having said all that, give it a try. It is possible that auto would be very effective in the right circumstances.

And remember, let's be experimental out there!

David
 
So you're doing thes timelapses at 2fps with 350d? How much time do you have on two 8GB cards?

Isn't there an actual interval setting for single-shot, where you can specify intervals between frames? Like 5 seconds, 30 seconds, etc... I haven't tried it out or looked into it much.
 
Tom Lowe said:
So you're doing thes timelapses at 2fps with 350d? How much time do you have on two 8GB cards?

Isn't there an actual interval setting for single-shot, where you can specify intervals between frames? Like 5 seconds, 30 seconds, etc... I haven't tried it out or looked into it much.
Click to expand...

Yes, in INTERVAL mode you can set interval at 2F which is 2 frames per second. However, you can only use INTERVAL settings in a 60p or 30p time base. Not in PN.
There is no benefit when it comes to space on the card and boosting light exposure when using INTERVAL.
 
But if the camera goes into pause mode for 15 seconds between frames, it is not recording to the P2 cards, right? I really don't know how it works. I was going to investigate today and tomorrow.

But shooting 2fps at 350d is PN? So the shots can last for a long time?
 
Tom,

The P2 cards playback the time lapse recording in real time. So you immediately know if you got what you wanted. Love the P2!

The record time in time lapse just requires some math. The recording will be played back in real time which is based on 30fps (all of the recording formats required for Interval are 30fps), it may be 29.97 but for the purposes of easy calculating use 30, it has never failed me yet. The counter in the camera still shows the time recorded on the cards. It will still show the real time available space (8min on an 8gig card). In the recording formats required for Interval the recording time is 1 minute per Gig. 30fps is 1800 frames per minute. Multiply 1800 frames by the total minutes of available recording time. An 8gig card will record 14,400 frames which is 8 minutes in real time playback.

Only the frames selected for recording will be recorded. Try this; set ONE SHOT TIME at 1F(that's the default), INTERVAL TIME at 1s. Pick a shot that includes something moving i.e. traffic(cars or people), clouds, something constant. That will give you 1 frame/second recording time. Record that for 5 minutes. Play it back in the camera and see what you think. Then just change the settings and experiment. The general rule is Interval time increases with slower action i.e. a growing plant.

I have used 1 frame/second in film and video with great success. Sorry I can't show you my amazing HVX time lapse shots. It does a fantastic job! I leave the camera at 180d shutter and expose for the shot normally.

Good Luck!
David
 
Time Interval Question

Time Interval Question

Here's a noobie question:
Why did it take around 2 hours for an interval shot, when I was shooting 60p with interval set at 1s on a 4 gig card?
Any help is much appreciated, Thanks.
 
David Trenkle said:
Tom,

The P2 cards playback the time lapse recording in real time. So you immediately know if you got what you wanted. Love the P2!

The record time in time lapse just requires some math. The recording will be played back in real time which is based on 30fps (all of the recording formats required for Interval are 30fps), it may be 29.97 but for the purposes of easy calculating use 30, it has never failed me yet. The counter in the camera still shows the time recorded on the cards. It will still show the real time available space (8min on an 8gig card). In the recording formats required for Interval the recording time is 1 minute per Gig. 30fps is 1800 frames per minute. Multiply 1800 frames by the total minutes of available recording time. An 8gig card will record 14,400 frames which is 8 minutes in real time playback.

Only the frames selected for recording will be recorded. Try this; set ONE SHOT TIME at 1F(that's the default), INTERVAL TIME at 1s. Pick a shot that includes something moving i.e. traffic(cars or people), clouds, something constant. That will give you 1 frame/second recording time. Record that for 5 minutes. Play it back in the camera and see what you think. Then just change the settings and experiment. The general rule is Interval time increases with slower action i.e. a growing plant.

I have used 1 frame/second in film and video with great success. Sorry I can't show you my amazing HVX time lapse shots. It does a fantastic job! I leave the camera at 180d shutter and expose for the shot normally.

Good Luck!
David
Click to expand...

hmmm.... so what am i doing wrong here...?

For some reason I can't seem to change the one-shot setting or interval setting.... or the pre-record setting. I select that item and press the II in the middle of the thing but nothing happens. all of these menu items appear blue and it seems I cannot change them. im sure this is some noobie mistake.

I don't have an SD card. Is that something I was supposed to buy? :cheesy:
 
Seems you cannot change these parameters when one of the cine-gammas have been chosen.

Am I wrong?

Gunleik
 
Hahaha... I just did a timelapse of my lazy dog! too cool! yep, with cinegamma on you can't do timelapse... stupid.
 
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