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Shooting Timelapse Sequences of Cityscapes

I have a time lapse shot coming up and I'm thinking of trying a longer shutter speed than I've usually used.

I need about a hundred frames and I'll take them over a four hour period.

Thanks for any thoughts,

D.P.


What exposures are you thinking of using? Are you shooting day or night?

From the header, I assume your are shooting a city, but Skyline or street and building details? Are you trying to compress 4 hours into 100 frames, or are you looking for a time of day thing?


Well... the Norris starts off at 1/16th and goes longer from there. I have quite a bit of experience with the 1/16th and 1/8th settings and I wonder if I'm *missing out* by not having tried longer times on this well worn subject.

The frame is a cityscape skyline (wide) with the sun going down about a third from the edge. Camera position is building top; 1200 feet. I'm formatted super-35 and need a sunset and sunrise, both. The cut will take the best five seconds going both ways; meaning night to day, then day to night. I'm quite happy with the 1/16th look but the director is encouraging me to tend towards the abstract...

I'm planning on shooting four hours around each *event* using a thirty-second interval.

Thanks,

D.P.


I was very happy with the New York Sunrises that I shot last year with 1/3 second exposures, I also used this for shadows moving across Broadway, shadows down one side of the street across the road and back up the other side.

The longer exposure seemed to smooth things out a lot.

Too much Tuborg Gold, the speel chucker is going to earn it's money tonight :-)

Cheers

Geoff Boyle.


My experience is that a 30 second interval is on the long side, clouds can move so quick across the frame that they are only in the frame for a couple of frames (depending on lens choice and clouds-passing-speed of course) I used to go for a 15 second interval, nowadays even more towards 10 seconds. Or you might try a 15 second interval and speed it up in post. Good luck

Mick van Rossum


What kind of lenses are you shooting on? You can try putting on 10:1 zoom and shoot 2sec./exp. frames with a slow zoom out from the sun. Clouds tend to look more 'milky' and the movement does not look quite real. Of course you're going to be using tons of ND (seven stop difference).

Are you thinking of panning the camera through this sequence? Maybe you can recompose into the setting sun?

Good luck, sounds like fun,

Duraid Munajim

Chriss


Longer shutterspeeds will tend to take the "edge" the frenetic activity of things like cars, clouds, and trees. They will become more blurred; longer car light trails at night, whispier clouds, more transparent moving cars in daylight, blurred trees (depending on wind conditions). At around 1 sec exposures, night cityscapes begin to take on a surreal lighting effect. You begin to get the impression that massive amounts of lighting was employed, because the buildings that would be impossible to light _are_ lit by ambient light. The longer the exposure, the brighter the normally dark buildings become. Faster stock also helps. Also, you get moving clouds in the night sky. If you want to see and example of this, look at the backgrounds for the opening to ABC's Monday Night Football. It's about a minute long opening that starts at 9pm SHARP eastern time (if you wait till after the commercials, you've missed it). These backgrounds are at about 2 second exposures with wide apertures on Vision 320T, some on Vision 250T. However, one of the biggest challenges you have is taking the light change into consideration. Lots of ND and/or deep stop on the lens in the daylight, gradually changing to a clean wide open lens.

Moving the camera is possible by hand, but tends to be a bit jerky. Better to use a motion control head to get smoothest motion.

Good luck,

Don Canfield


Don,

I recently shot some pixilation of a Mardi gras parade that came out well, I did a lot of moves (zoom, pan, tilt) @ about a 2 SEC interval. No intervalometer, just playing around- but now I want to do it right and found your post very helpful.

Question tho, any idea what to rent for shutter control on an aaton? I like the thought of leaving a 2 sec dwell. also, if using an ND it would seem to be abrupt to remove it, but I'm guessing you timed it out?

Thanks again, Caleb


For instances such as that which started this discussion, a cityscape, changing ND on the lens and compensating with the iris works. You've got to be in a situation where the interval is long enough so you can swap the filters, and the focal length and distance to subject combination sufficient to allow for the slight shift in depth of field that will occur. For example, if you swap a ND9 to an ND6, you would have to stop down the iris one stop to equalize the exposure. I think the last time I did this I worked in a 2 stop range on the lens, then changed filters. I was working with 3 cameras, longest lens was about a 35. Cameras were on top of a building in midtown manhattan, looking north. Closest building in frame was a couple of blocks away. We worked with a bunch of ND (don't remember how much), at about a T16 in full daylight. As the light began to move in the afternoon, I opened stop gradually (following the light drop). When the lens got to T8, I swapped out 2 stops of ND, and stopped lens down 2 stops, and continued to follow light down. This continued till after sunset, by which time I had lens wide open, and no ND. Exposure pops, if any, were burried in the light change, clouds, and timelapse action.

In time lapse, there are pronounced areas of right and wrong at the exposure extremes, but a very wide gray area in between with lots of forgiveness where lots of things work quite well, even if they don't seem like they should.

Don Canfield


These is a rather neat British invention made by Camera Dynamics (I think).

It consists of a micro processor controlled stepper motor and works with a clockwork Bolex (possibly with other cameras but this is the only one I know of). It's far more versatile than most other systems as it allows for time exposures, variable intervals between exposures and even ramping of time intervals between exposures. If you're still looking, give me a call at OpTex on +44 (0) 181 441 2199 and I'll see if I can help. Apologies for the delay, but I've only just reconnected to the list.

Brian Rose


Thank-you to those who contributed to this thread. Your input was welcome advice that helped me choose the following scenario....

Cityscape Night - to - Cityscape Day

1/4 second exposures,

Single frame burst,

15 second intervals,

Arri III / Norris Intervalometer/ Zeiss 18mm T1.3,

Wide open Night... to ... 1.2ND T11 Day,

Kodak 5246,

Very light, fast moving, high altitude (cirrus?) cloud at night, Clearing to pristine blue sky at sunrise plus thirty minutes.

Unfortuantely, we had problems with the Norris that I can only attribute to EMI (electro-magnetic interference). This combination of hardware WILL NOT WORK in the prescence of strong EMI. We were set up on a building top with some FM/Cellular/Microwave transmitters and things did not go at all well.

Strangely, the shots did work when the sun was not in shot. All the pre-sunrise and post-sunset footage worked but capping shutter/run-away-motor problems ruined the scripted rise and fall of the sun. We tested and tried EVERYTHING including units from two different suppliers and more work-arounds, foil, cable-substitution and voodoo incantations than I care to list. I stand by my suppliers AND my assistants; both performed exhaustive pre and post shoot tests

I need to *repair* this situation and what I would like to do is repeat the exact shot with a manual single frame camera that can do 1/4 second frames ( MECHANICALLY, Manually) ) for me. What should I be using? I'm guessing the answer is some kind of animation camera. Inching the 435 has an immediate appeal but I can't conscionably ask the producer to bring me another camera that is so dependant on electronics. What's in the big cupboard that can give me what I need?

Maybe those lead aprons they use for X-Ray techs would work.

(un?)Fortunately, I have an understanding producer who needs results not research!!!

BFN,

D.P.

BTW, I must take this one on the chin for not spotting the problem in advance. I have apologised to the producer but still feel a little put out. I DID make clear to several different suppliers what I was planning to do and NO ONE mentioned it might be problematic. Post meltdown dialoguehas included some references to this problem and THAT REALLY STEAMS ME.


The best type of camera for doing Animation and Time lapse, is a camera with a focal plane shutter (IMHO). In the animation house that's what we used (Mitchells, Rackovers, and Fries Conversions).

With reflex conversions you do have to compensate for the light lost through the Pellicle. Many Conversions use Nikon mounts, however I am sure that there are other mounts available ( I know of one fellow that has both Leica and Panavision Mounts for his Fries Conversion).

The advantage to the Focal Plane shutter camera is that you don't need a caping shutter, as NO light leaks through to the film.

The advantage to the Mitchell is that it has Great Registration, and not generally being considered a Sound camera, and also since it is not in such great demand, it can be cheaper to rent.

NOTE, NOT all Models of Mitchell cameras use a Focal Plane Shutter, so Make sure of your order.

The other disadvantage to Mitchells with a Pellicle beam spliter, is that Not all lenses will fit on them, I believe Certain German Lenses with exceptionally deep Mechanical protuberances, just won't do it. This does limit your use of Zeiss Glass, which is a pity. I'm not sure which lenses do work and which don't.

As to the Norris, it is a fine machine, however in my experience I found that it had a few quirks. The mechanical counters tended to Add a frame every so often, ( if I remember it was every 50 t0 70 frames). This was solved with the electronic frame counter. I found that when powering up, the Norris would take a frame, which meant that you couldn't break a shot in the middle to take a rest, unless you left the intervalometer powered up.

They also were very sensitive to voltage shifts. This was probably only a problem where I was working as the Power supplies were not always heavy duty, and would drift. Get a Really good Power supply, or LOTS of Battery Power.

Also, remember in Time Lapse, and Animation. Sync has a whole different meaning, sounds like that wasn't your problem, but never hurts to be TO SURE about that.

Good luck with the next one.

I believe Cinevision in New York has and rents a Mitchell/Fries Conversion with a Focal Plane shutter, and Probably a Norris to go along with it.

(Possible a video tap as well)

Steven Gladstone


I'm no stop-motion guru so maybe I am a good person to make a suggestion here. Fifteen years ago when I was working at Victor Duncan in Chicago, the 'state of the art' stop motion rig we had was a Mitchell S35R Mk II (usually called just the 'Mark II') with a Mitchell animation motor and a clockwork controller which had a big dial on it like a darkroom timer. I went out with this setup a few times as an AC and it worked just fine: no ups, no extras, no problems. You need a screwdriver to set the Mitchell's variable shutter (on top of the camera) and the motor and controller work off AC, which it sounds like you would be able to come up with.

The only tricky thing about this rig is making sure that both motor and camera movement are in the correct 'parked' position before putting the motor on. As I recall it is possible to get it 90 or 180 degrees off. But that's basic ACing--this is about as 'meat and potatoes' as you can get.

There are now Fries motors for the Mk II which do the same thing as the old setup, probably much better; however they may also be electronically vulnerable as well. Heck, maybe you should take a (tested) electronic and clockwork controller both with you, so you've got a backup either way!

The weak link for the stock Mk IIs was the BNCR lens mount, for which we had only ancient Super Baltar lenses, so we nearly always recommended the cameras with a Panavision hard front which would allow you to use the Pvision lenses. Probably a supplier like Clairmont has adapted them to PL mounts as well. There are still lots of these cameras around, though probably not on the front shelf of your local rental shop. Ask around and you'll find one.

This is an old-fashioned, low-tech, mechanical method. As such it is not at all fancy or sexy and may be looked at askance by younger producers. (The same kind who recently asked 'what is this???' when I had an Arri IIc brought out for a hand-held shot.) But it does work.

Best wishes,

Alan


If I recall that camera has a spinning Reflex mirror shutter. Not A Focal plane shutter. I've used it for animation, with exactly the motor set you described, however, for extended intervals between exposures A capping shutter is a great thing to have.

With the Focal Plane Shutter, no caping shutter is necessary.

Steven ( I love Mitchell Cameras) Gladstone


The Mitchell S35R/R35/Mk II et all all have a spinning mirror, with a real (and variable) shutter mounted behind them. So you get the best of both worlds -- except for the fact that the flange focal distance is so great as to limit you to Panavision (when the camera is modded) and BNCR and S35R lenses.

But it's a pretty cool camera.

I have a Mitchell GC I probably am going to Fries-ize. Still trying to decide between the cheaper pellicle version (uses cheap Nikon mount lenses, or other still lenses) or the spinning mirror version. Anyone?

Jeff "cap this shutter" Kreines


Have you called Dan Norris and asked him?

Perhaps a lead box around the intervalometer control box?

The old Mitchell motor would be better. Think I finally sold mine... you can easily make a Mitchell animation motor using a SloSyn 72 RPM sync motor, cam, microswitch, capacitor, and a panel cut to fit the side of the Mitchell.

Oops, you are using an Arri III.

Sorry, no ideas for you.

Jeff Kreines


The focal plane shutter of the ACL (non variable)makes this camera a _very_ good choice for 16mm time lapse.

There is a Norris motor for the ACL too.

--jp


Yes, though I always wondered why Dan attaches it to the inching knob instead of coupling it directly. Yes, I know, it's easier!... but still....

Jeff "Bolexes are also good for time lapes, Mitchell 16s and Maurers too, but I have an intervalometer for my Aaton" Kreines


Gee, I've heard of some flakey things with Norris motors, usually having to do with power problems. This is a new one though. Maybe Dan Norris has a suggestion. Other than that, alternate camera/motor combos that might work follow. I've indicated limitations that I've found with each.

Mitchell with Lynx C-50 motor and timelapse sync box. Source: MCRS in LA;Stone Engineering in LA; possibly Cinevision in NY. Limitations: Lens selections. Fries with arri shutter can use PL, Panavision, Nikon, but require capping shutter, though at a 15 second interval you may get away without one. TEST THIS FIRST! Fries with pellicle beamsplitter and focal plane shutter can use Nikon, BNCR. Does not require capping shutter.

Unconverted by Fries uses Mitchell mount, BNCR, or possibly Panavision.

Panavision camera with Timelapse synchronizer. I've used these a few times, and the best ones came from Victor Duncan in Atlanta. VD Atlanta has modified magazines that have very low torque takeup motors. These mags provide just enough takeup torque to pull single frame out of camera body. If normal torque is applied, mag motor can pull film after the motor has stopped.

Mitchell with Jackson/Woodburn motor. This is an English motor, and I've only ever seen them twice in the US -- once on a motion control shot in NY last spring. Equipment came from Samuelson's in London. The other time was at ShowBiz Expo in LA in June. I don't know of any US suppliers. Limitations are the same as listed above for Fries.

Mitchell with old AC powered animation motor. Limitation would be listed by the supplier, if you could find one of these antiques. Try Cinevision in NY. Mitchell with steppermotor and motion control computer. This is really an overkill solution to the problem, but is would work. See above for camera limitations.

Wish I could offer more help. I really hate weird flakey problems like this!

Don Canfield


As a real world production tool, the mirror conversion probably is more versitile. Lens mounts include PL, Panavision, Nikon (probably others), viewing system is FAR brighter than the pellicle. However, the focal-plane variable shutter is completely removed and replaced with an Arri-like spinning mirror shutter. This means fixed 180 degree shutter, and the shutter is not light-tight enough for long timelapse or stopmotion animation.

Pellicle version is limited to BNCR, Nikon (and other still lenses), some Panavision (check with Fries). Varible focal-plane shutter is preserved, intact, and usable. It's possible to install an internal capping shutter if desired. It's a great animation/optical/motion control camera. Because the image must pass through 2 beamsplitters if you use video (pellicle and tap splitter), viewfinder image is quite dark. There is a movable mirror option which will allow you to direct all light to video OR viewfinder. Maybe this could be modified similar to the Fries door for the Mitchell S35R/R35/Mk II which provides an orientable finder with a selection to send all info to the finder, all to the video, or split it 50/50. Oh, and finally the pellicle drinks up 1/3 stop light (which is sends to video/viewfinder). No shutter flicker, though. (But this makes syncing to a monitor a nightmare.)

In my opinion, the mirror version is much more cameraman friendly, where the pellicle is more technician friendly. In regards to wide lenses, I know there are issues with different lenses on either version. Check with Doug Fries.

Also, in my opinion, there are other motors that you should checkout besides the Fries. Lynx Robotics C-50 and the English-made Jackson/Woodburn are worth considering. You can find both of these advertised in American Cinematographer.

Don Canfield


Here is a belated response to the request for info ragarding time lapse of cityscapes at sunset. I recently shot a commercial project that required just such a scene. We set up an Arri 35-3 overlooking downtown Cincinnati, facing towards the west. The location was chosen for a great raked view of the major buildings as well as a foreground freeway which would be important once day became night. My stock was 5245 and I used a Zeiss 25mm Super Speed lens. I stopped down to T-11 and with the Norris intervalometer set at 1/16th second exposure shot three frames a minute (one every 20-seconds) and continued this interval for an hour. By the end of this hour the sun had set and day had become night. I then opened the lens up to T 1.3 and switched the Norris unit to 1/2 second exposure at the interval of 1 frame every second and proceeded to run 5 seconds of screen time. This longer exposure time (coupled with the brief interval between frames) yielded great headlight and taillight streaking from cars on the foreground freeway.The shot was steadi-gated during transfer and in post a long registered dissolve smoothly blended the gradual fade from day to night with the night city scape for a truly beautiful scene. The 50 ASA rating doesn't sound like much but wide open at 1/2 second yielded tremendous detail in the buildings.



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