[geoffsims (Geoff)]

Hi all,

While there is already a general TSE photography thread, I thought it may be useful to begin another, specifically discussing time lapse. Considering time lapse is all the rage now, is anyone going to attempt this? Has anyone seen any *good* attempts at this in the past? I certainly haven't.

It is the "holy grail" on steroids; the light change happens over a much shorter time frame. I am hoping we may be able to determine the best way to tackle this, and I begin with a few thoughts:

1. It seems like a no-brainer to use specific eclipse camera control software (i.e., Orchestrator or Maestro). These can control the camera via USB/serial cables, and have the ability to scripted with events relative to the eclipse contact times. Effectively, you can predetermine your bulb ramp and script it exactly as you require.

2. How to tackle the timing? The totality portion of the eclipse is so short compared with the duration of the partial phases on either side. If you shot every second for instance, and played back at 30 FPS, partials would run for 2 minutes either side of the 3 seconds totality (VERY rough calculation assuming 1 hour partials either side of 90 second totality). Although not physically realistic, could it be worthwhile shooting at a lower cadence throughout the partials, in order to give a bit more time to totality during the final sequence?

3. I present some tests I ran during TSE2008 in Mongolia. Not intended as time lapse research, they may indeed help. I shot some images at various timess (relative to 3rd contact: mid eclipse, C3+10s, C3+20s, C3+30s, C3+1m, C3+2m, C3+3m, C4+4m) at FIXED exposures. For the curious, I was using a Canon 400D, 17mm lens at f/4 and ISO 100. The exposure times are 1/30s and are attached to this message. They may be useful in probing how the light changes at various times, and how to tackle this. All images were shot in RAW and converted to TIFF then JPEG using default settings. Of course the same happens prior to 2nd contact, in reverse order.

4. It is worth noting that using the above camera settings (17mm, f/4, ISO 100) an exposure of 1/4s to 1/8s is optimum for the totality eclipsed Sun & sky portion of the photo, while exposures of 1s to 4s light up the landscape sufficiently. Usually, I combine a number of exposures to produce a nice landscape shot during totality. Similar HDR techniques could be employed for better dynamic range during totality, but timing could be an issue.

Thoughts, anyone?

cheers
Geoff