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Old March 7th, 2006, 06:25 PM   #1
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Recording Solar Eclipse

Hello, I'm not sure if this this right forum.

I'm going to Turkey for the solar eclipse later this month. Now I had no intention of pointing the camera at the sun except during totality. Does anyone think that there will be enough light to damage the CCD just at the point where totality ends when the diamond ring effect occurs?

My main aim is to record scenes around the village. At some point I will come out of auto exposure to stop the camera compensating for the darkening effect. I don't know if it's best to go into manual exposure before the eclipse begins, or at some point later. Does anyone have experience of this?
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Old March 7th, 2006, 11:29 PM   #2
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You simply need to control the amount of light getting into the camera. If there is too much, it will ruin your shot. I don't think anyone is going to sit around with the iris open while the camera is pointing at the sun. I'm guessing that you will have the ND filters on and the iris stopped down a bit. If you are really concerned, you could add an external ND filter or a polarizer to knock down the light further. Your eyes are more prone to damage. For your eyes, you would need welding goggles that appear totally black in anything but strong sunlight. FYI, the UV coming from the welding process is even worse than the sun and I've seen many programs where people were welding. Remember that the difference in a camera's maximum exposure and minimum exposure with ND filters is orders of magnitude. Five f-stops and ND2 is not 8X darker than full exposure (or 1/8th the light). It is more like 2 to the 8th power, or 256 times darker (assuming ND2 is 3 f-stops). To make it easier, your camera's minimum exposure is probably less than one half of one percent of it's maximum exposure.

For shooting the experience, you might want to make sure there is some sort of artificial light in your shot so that you will have a frame of reference for your video. When people see that porch lights (or something similar) are looking bright at noontime, they will get a better impact of how dark it became. At least bring a flashlight. Car headlights would also work, so try to have a road in your background. Of course, don't forget to record people's reactions!

Oh, and just in case the eclipse is the sign of Armageddon...don't forget to bring your towel. You can't help but respect a man who always knows the whereabouts of his towel.
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Old March 8th, 2006, 11:05 AM   #3
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Thanks for your suggestions especially about including artificial light. Though knowing my luck, and knowing Turkey, there will be a power cut at the moment you just don't want one. So I think the flashlight idea is a good one.
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Old March 8th, 2006, 02:16 PM   #4
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It's on a Wednesday, so you probably don't have worry about armageddon. :)
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Old March 8th, 2006, 10:04 PM   #5
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Darnit, Adam! Now he will let his guard down! You forget that it will still be Tuesday in Hawaii and the Aleutian Islands.

If you can get a few cheap flashlights that are still bright enough to show up on your camera, you could pass them out to people. Kids may have fun with flaslights in the middle of the day. You could try using a lighter (not for kids) if your camera is sensitive enough to pick up something as strong as a candle. I'm guessing that the people's reactions will end up being the most important part of the video. You might also want to make sure there are some of those paper pinhole viewers or "eclips glasses" for people so they don't go blind. The "eclipse glasses" are cardboard with dark plastic tinted gel and sell online for about $1, but I don't know if you can get them in time. I'm guessing there will be local sources of the glasses and you may want to buy extra in case local people are unprepared. A small hole in a paper with another sheet to shine the image on allows people to see the "shadow" of the eclipse (not to view directly). A set of welding goggles would also work. If you need to save money or space, you can buy just the replacement glass and carry a few of them for people to try. The glass is usually about 5x7 or 5x3 and beveled on the edges, so it should be safe to handle. It comes in different strengths, so try out which makes the sun look best. I'm guessing #8 or #9 which is less than the standard #10 (welding is brighter than the sun).

I permanently damaged my left eye as a child by looking at the eclipse through a pinhole viewer instead of shining the image on a piece of white paper. Fortunately, I sensed I should only look briefly, so the damage is slight. I'm sure the cheap glasses are easier, just make sure the people around you are protected.
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Old March 8th, 2006, 11:22 PM   #6
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Hey there, I'm going to Turkey as well with an HC1.

Here is what I have done: I made a filter cell using Baader Astrosolar film, which fits over the teleconverter.

While the CCD won't be damaged directly by exposure to sun, the lens optics will focus light inside the camera and things will heat up - a lot. A regular ND filter will not be enough. Let me emphasize this again: exposure compensation and iris on the camera take effect *after* light has passed through the objective lens - they may make a usable image, but the lens is still focusing a *lot* of solar light on the innards of the camera. So when shooting the sun, make sure you have your filtering *prior* to the objective lens.

Here is a picture of the camera with the cell mounted, and here is a picture taken through the camera, with exposure stopped down 3 clicks and maximum zoom + teleconverter. (At neutral exposure you get a bright white disk.)

I found a couple of things while testing the setup. First, with the teleconverter and max zoom, it is very sensitive to vibration. So make sure you mount on tripod, set steadyshot to max (conv lens option) and *use remote control* to start and stop recording. Second, at that zoom, the sun will move quite a bit during the time of the exposure. Basically it will move the equivalent of 3 solar diameters during the eclipse. So figure out the solar track the day before, and frame your shot so that the sun will go from one side of the shot to the other. Third, use manual focus, and *secure the focus* ring at the right setting.

My plan is to shoot the partial phases with the filter, then remove it before the first "diamond ring", then replace it after the second.

If you are going to the Soulclipse party in Antalya, send me a PM, we can meet up. We can back each other up... also, I have a spare solar filter cell that will fit over the teleconverter.
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Old March 9th, 2006, 01:49 AM   #7
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Yeah, do what he said. That's what I meant! :) Yall have fun over there.
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Old March 9th, 2006, 09:03 AM   #8
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Whoops, didn't read the first post carefully.

Shouldn't have a problem with exposure during the diamond ring. All my other warnings and comments apply.

Definitely shift to manual exposure control early and stay on top of it.
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Old March 9th, 2006, 08:17 PM   #9
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Thanks for your comments Gian & Marcus. I don't want to do anything that will risk an Apollo 12 scenario. I think I'll wait for totality before pointing towards the sun, then reposition the camera after the second diamond ring

I'll be going to Goreme in Cappadocia. Some of the strangest landscape
http://www.cappadoce.ouvaton.org/anglais/
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Old April 12th, 2006, 10:37 PM   #10
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Here it is...

Went there, shot the video, here it is:

http://www.villamil.org/movies/totality%20PIP.mov

No processing other than inserting the PIP reaction shot.
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Old April 12th, 2006, 11:30 PM   #11
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Very nice! I knew the crowd reactions/video would be just as important as the actual eclipse! I have never liked PIP editing before, but this is a notable exception. Using two cameras worked out very well. What settings/filters did you use to shoot the eclipse itself?
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Old April 12th, 2006, 11:39 PM   #12
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Quote:
Originally Posted by Marcus Marchesseault
Very nice! I knew the crowd reactions/video would be just as important as the actual eclipse! I have never liked PIP editing before, but this is a notable exception. Using two cameras worked out very well. What settings/filters did you use to shoot the eclipse itself?
Thanks!

During totality, no filters. Just manual focus (based on painstaking rehearsal the day before) and manual exposure (a couple of clicks below what auto wanted to do). For the partial phases, a filter cell made with Baader Astrosolar film. I ended up with a lot of extra material, gave it away, you can see the photogs in the reaction footage putting it on their cameras towards the end...

In hindsight, much more reaction footage would have been nice.
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