Stop Frame Photography at night

[WhiteInsight]

Hey, I saw this stop frame piece a while back.
http://599productions.com/599/Timelapse_1.html

I have just watched a TV show on London over here in the UK and they had lots of night time stuff which was awesome.

I really want to give it a go, I have experience of using stop frame during the day, but I’m slightly confused about how exposure would work at night?

Surely 30 second exposures to get the trail lights are too long for this as each from would be completely different as lots of traffic would have changed?

I have searched on here, but with no luck.

If anyone can post up their experience I would be very grateful

Thanks :)

[Sorarse]

Looking at the length of the light trail from individual vehicles, I'm guessing that the exposure time was around 1 or 2 secs. Difficult to tell without knowing how fast the traffic was actually moving.

[WhiteInsight]

Yeah that’s true, I suppose the only way to find out is to try

I am thinking of ISO around 100 to keep noise at a minimum, possibly F.8 and its just the shutter speed I will need to experiment with. I just wondered if anyone else on here had any experience and could offer some useful tips
thanks

[canonloader]

Great link Cupra. Fantastic work. My guess is, they used a very fast lens, like 2.8, and Av Mode. None of those streaks are more than a second long, probably a lot less. Also, QT movies that are smooth like this one are at 30 frames a second. If you pause and play the movie and try and catch a car with streaks, you can see it didn't travel far at all, so my guess is, most of the frames were at 1/8 second or faster.

[Sorarse]

Great link Cupra. Fantastic work. My guess is, they used a very fast lens, like 2.8, and Av Mode. None of those streaks are more than a second long, probably a lot less. Also, QT movies that are smooth like this one are at 30 frames a second. If you pause and play the movie and try and catch a car with streaks, you can see it didn't travel far at all, so my guess is, most of the frames were at 1/8 second or faster.

If you expose at 1/8 sec, the most you are going to get is 8fps, not the 30 you reckon is required for the quality shown in the link. Most movie cameras only shoot at 24fps, so if you are shooting at that sort of rate, you will just get a movie of the proceedings, whereas that link is definitily not a movie but stop frame.

[WhiteInsight]

No worries canonloader, there are a few on there that are awesome, I’m gonna give it a go, I will use my 17-40 in AV ISO 100 or 200. I will try a frame every 5 seconds for about 30 minutes. I don’t fancy adding 360 odd clicks to my camera, so will borrow one from university to give it a go. Will give it a try using a laptop and let the Eos utility work out the shooting increments to keep things accurate.

[WhiteInsight]

Sorarse, from what I can see within a second of that movie there are about 7 or 8 frames. At the beginning of the film it states the real time was 2hour 48 minutes, whether that corresponds to each individual clip or the entire movie I am unsure.

Looking at the first clip it captures a car travelling over the bridge in about 3 frames, depending on that individual cars movement and how fast it was travelling, therefore I would say it was shot at about a frame every 2 seconds not 30 frames per second.

[canonloader]

If you expose at 1/8 sec, the most you are going to get is 8fps, not the 30 you reckon is required for the quality shown in the link.
What has the shutter duration of a single frame from a still camera have to do with a patched together QT movie at 30 frames a second? You can take 30 10 second frames of a night sky to get the stars and patch them into one second of video and it will look normal, only speeded up. Yes, film movies do run at 24, video for TV or monitors run at 30fps.

[Sorarse]

Ah, I see what you are saying now - the resulting patched movie is running at c. 30fps, not that it was captured at 30fps. My apologies.

[canonloader]

No appologies needed. I have been working with Macromedia, now Adobe, Flash for 6 years now, and unless you work with a program that uses timelines, you can't really get an accurate picture of how it goes together. :)

Essentially, when building a video, you have a GUI that shows a timeline broken up into frames. Then another setting that sets the frame rate, anywhere from 1 per second, up to 120. But, each frame, when clicked, is it's own stage, or work area, where you can put anything you want. In this case, the video was probably set at 30 fps, [and that's just my eyeball and experience making a guesstimate after watching this movie] then on each of the 30 frames per second, was added one of the stills from this guys shoot, then aligned on the stage so they all match up.

When the movie is played, this is what you get. It looks like a regular movie speeded up. But essentially, whatever image was added in any given frame has nothing to do with the overall rate of the movie.

This is how Subliminal Advertising works. One frame of something else can be slipped into a series of frames and you conciously don't see it, but the eye and brain caught it. :)