Timelapse Day to Night.

[Alexander Sutton-Hough]

I will be shooting a timelapse in the desert from afternoon into the night.

I will be shooting on a Gemini with Sigma Cine Primes and ND filters.

What's the best settings to accomplish the exposure Change? I only have experience with timelapse with DSLR. Which I will also have setup as back up.

[David Mullen ASC]

Maybe you should go out there with a meter in advance and plot the exposure change so you can figure when to pull NDs versus do a stop change versus an ISO change.

[Robert Hofmeyr]

I'm no timelapse expert, but don't forget to consider using HDRX with 6 stops and exposing the X-track to the right during the day. Obviously if your subject requires motion blur during the day this will not be a good method. This should be enough to get you past sunset, but if you want to see the stars come out, I think you will need to make an exposure change or remove ND. Also look at the frame averaging option as you can use this instead of NDs so you don't need to fiddle with filters in the middle of your timelapse.

[Björn Benckert]

I would stack nd’s in small even increments of stops.

The kippertie is perfect for this. Then you got clear, 1,2 1,5 1,8 and 2,1 on the same nd disc.
And you can go upp /down really quick. If you make sure never to hit the stoplights/overexpose. It should be fairly simple to make seamless grading transisions in post.

I would not change iso in camera, it does not do any difference.

The only factor in camera you can play with if you run out of NDs is exposure time. But I usually leave it at 360 wich has huge benefits as then you can merge frames together and keep the motionblur intact.

So preferably shot quadrouples of the speed you want with 360 shutter then you have the option to speed up in post.

Also another super nice feature is the in camera frame summing and average but those takes a bit of time to get your head around and is only needed if you run short on ssd.

A 2tb longtake mag from kippertie is peefect if you want to shoot for a full afternoon and a hotswap battery option.

[Alan Greene]

I agree, use HDRx and frame averaging (great idea), and change NDs as needed. I strongly recommend not adjusting the iris, unless you do it continuously with whatever fancy motor thingy can do that for time-lapses. I also have the Sigma Cine primes, and a sudden change in iris will cause visible differences in vignetting and even color (depending on which focal length you're using). If your subject is contrasty and colorful, it may not matter as much, but if you have subtle gradations or will need to juice the saturation in post, there could be a real problem.

[Brian F Kobylarz]

Agreed with the above mentioned techniques with a couple of notes:

When you change ND, consider adding a single flash frame of a color chart.
That will be invaluable when in post.

Carefully consider your power requirements.
If you need to replace batteries during the time lapse, you lose all the frames you would have recorded during power down, replacement and boot up.

If you are using a dual sled, the camera can shift ever so slightly when changing batteries.
Make sure you are very locked down...

My best practices have taught me that the best approach is to power off-camera with a DC cable from either a sled or block batteries such as VCLX.

Good luck!

[Daniel Kelly Brown]

I usually just use sony A7rIII with built in intervelomeater on ael low or med. Lock the aperture down wide open or near it, limit iso depending on what moon faze is currently.

Really to do it right you need to use the holy grail technique and LRT timelapse - https://www.youtube.com/watch?v=PafMIcw2QaY

Your going to have a really hard time getting a good night timelapse on a red camera let alone a day to night timelapse... Your going to spend eons in post to get it right.

Edit- sony a7riii and above lets you limit your shutter speed as well, so if you wanted to do a 20sec or 15sec to get more crispy stars then you can do that now in auto mode. Also I have found that sony seems to have the ability to auto meter exposure much much better then nikon or canon when going into complete night darkness. Not sure about canon or Nikon mirrorless, but seems to be the case with DSLR.

I must be missing something because every time I have tried to do long exposure on the red it just ends up with tons of hit pixles. Suppose I have not tried this since auto blackshade has been out.

[Mark A. Jaeger]

Here's my take on this. I too mainly shot DSLR T-L but now I'm using DSMC2. First, what's the end of the sequence?
If you just want to go to the dim afterglow of sunset, you can start with f/22 or whatever maximum is for your lens and then add the minimum ND necessary to get a decent daylight exposure. As the light falls off, try to keep your exposure changes to 1/3 stop but follow the light down keeping the left goalpost free of noise (if you can). At some point you're going to be wide open and that's the beginning of the end. Let the light fade, the left goalpost fill and then stop. BTW: fast glass, like T1.5, is preferable for this.
If you're going into full night with stars, et al you will need to get rid of the ND. However, this is a huge EV jump in the sequence if you're taking out 3-4-5-6 or 7 stops. The Revolva is a preferable program as 1 stop changes are practical. This extends the useful range into full darkness. If you don't have the Revolva you're looking at a jump that de-flicker programs will have issues with. It will take many, many, passes to smooth the curve.
BTW: I don't now have Revolva but I anticipate purchase soon for this very issue. I want to do some testing with 1-stop jumps to make sure I can smooth the transitions.
I seriously suggest you test your method somewhere close to home. There are issues in this procedure and hours will be consumed in getting it done = much better at home. Good luck

[Karim D. Ghantous]

This is a great question - I never even though about it before!

[Chris Bunney]

This is inspiring me to try this.