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Shooting Sunrise With Time Lapse

Hi,

I have a shooting of a sunrise. I want to film short before dawn at 3fps (Aaton XTR S16mm) for about 20 min. since I start practically in the dark and finish at late dawn, the question is how do I deal best with exposure. I think to expose for dawn and let the rising light level naturally control the exposure on the film.

Any suggestions

Jens Klein
DoP Malta


>how do I deal best with exposure. I think to expose for dawn and let the >rising light level naturally control the exposure on the film.

I recently did a time-lapse test on a Bolex with similar conditions. I started wide open and let the sun blow out the frame, which consequently didn't produce the results I wanted. I did another test where I stayed wide open until the film reached optimum exposure, and then compensated as needed. This technique yielded the best results. The problem I ended up with however was predicting a good sunset. The sunrises tended to be consistently beautiful, but not the sunsets.

Does anyone out there know the conditions that produce colourful sunsets?

Erik "stock footage!" Messerschmidt


Erik Messerschmidt writes :

>Does anyone out there know the conditions that produce colourful >sunsets?

In the simplest of terms...smog.

Smog, or any airborne pollutants, including dust, acts as a filter creating the colors we associate with beautiful sunsets.

Cliff Hancuff
www.ClearDaySoftware.com


>beautiful, but not the sunsets. Does anyone out there know the >conditions that produce colourful sunsets?

Low atmospheric pressure helps, and you need sediment (smog) in the air. When volcanos erupt in the south, we (in Los Angeles) get great conditions for storms and beautiful sunsets.

Mike Rosenthal


>Does anyone out there know the conditions that produce colourful >sunsets?

Dust in the air as others have said. (Or smoke - bushfire season here does the trick sometimes).

A low horizon, to get the sun's rays skimming through as long a distance of air as possible.

Most importantly, light, high clouds (nimbus? cirrus?) to produce the texture. I spent a summer on the volcanic desert interior of Iceland where the sun spent most of the day/night either setting or rising. Stunning skies when the wind brought the high clouds and whipped up the dust .

Dominic Case
Group Technology & Services Manager
Atlab Australia
web: http://www.atlab.com.au


I've generally done this by exposing for a 2 to 3 stop overexposure of the final light and then just let it all sort itself out.

It's amazing what you can fix with a ramp in TK!

Cheers

Geoff Boyle FBKSTS

Director of Photography
EU based


>I have a shooting of a sunrise....for about 20 min. since I start practically >in the dark and finish at late dawn, the question is how do I deal best >with exposure.

This was a few years ago...but going against the advice of a motion control operator (a friend of mine who was helping me with this) I actually adjusted the stop on the lens manually. Got comfy in a chair with my spot meter and tried to guess what the light would do in the next few minutes. I remember feeling like such a hack since my friend had so much more experience with this, yet every cell in my body wanted me to get more night exposure. I was so worried it would flicker and pulsate but it turned out fine.

The secret, I thought, was to make "1/10th stop" adjustments...absolutely tiny, zen-like adjustments. And I did them slowly during the exposure cycle (shutter open), so in a way that change would sorta show as a "1/20th stop"...in theory anyways. Its one of those theories that come to me in desperate moments at 5am. Reflecting on it now makes little sense.

Once the sun nears the horizon you're trying to close down the lens pretty quickly. And all this method really achieves is to let you see dark-blue glow sooner than you might had you left the lens set for day/ext sunrise. Conversely you might get better highlight detail at the end if you follow through...but film can handle that pretty easily. I'm not sure if the gains were worth the risk. It's so easy to bump the stop and lose your place when you do this sort of thing.

The most confusing part was changing the shutter speed on the Norris Intervalometer (between frames) and then compensating the lens properly without gross errors. Was necessary to keep my exposure on the lens (1.4 to 11) as I came out of starry-night-sky exposure. That procedure held the highest risk of failure and I attribute any success to strong, black coffee well before sunrise.

Make’s one wonder what would one do without good, accurate t-stop markings ?

Mark Doering-Powell
LA



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